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3p242j
|
what's the point of a hov lane? why not just let everyone use it to prevent traffic backups?
|
There's a lot of highways around here that are 3 lanes wide, with one being a hov lane, that you have to pay for, why not just open that lane to everyone and have 33% more road for drivers?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3p242j/eli5_whats_the_point_of_a_hov_lane_why_not_just/
|
{
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"cw2he2c",
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"cw2hhef"
],
"score": [
6,
2,
2
],
"text": [
"It's to provide an incentive for people to carpool. If more people had 2-3 passengers in their cars, that would make the regular lanes less congested.",
"1. Because you would have 50% more. \n\n2. The point of the HOV lane is to encourage ride sharing so there are fewer cars on the road, and less use of resources. The traffic-free HOV lane is the prize you get if you take part. \n\nI'm not saying that I 100% think this is a great idea that always achieves the desired effect. But that is the reasoning. ",
"You pay to use your HOV lane? I know California is making HOV lanes premium lanes, but I have never heard of paying to use a regular HOV lane. As for why it's restricted, it's to incentivize people, if 4 individuals carpooled, that's 3 less cars on the road, mumtiply that by 100 and that's 300 less cars. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
7hoqhc
|
How much current USD would five shillings in 1659 Massachusetts Colony be worth?
|
Say you were an average inhabitant of the colony and had five shillings tucked away. If that were a modern day savings account how much would you have?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7hoqhc/how_much_current_usd_would_five_shillings_in_1659/
|
{
"a_id": [
"dqss7hq",
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],
"score": [
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2
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"text": [
"At the time, they were using the 62 shillings per pound, and a penny weighed 7 23/31 grains. A shilling was 12 pence. \n\n5 shilling = 60 pence. \n\n60p = about 464.52 grains.\n\n464.62 grains = 1.061989oz\n\nCurrent silver price is $16.35 an ounce, so that would make 5 shillings worth about $17.36. \n\nIsnt there some odd story about 1652 pine tree shillings, or them printing 1652 as the year for several years to avoid taxes or something? I might be making this up, but its probably relevent to the topic if im not. \n\n",
"Are you asking what the purchasing power of 5 shillings be, as in, adjusted for inflation, how much would 5 shillings be worth in today's dollars?\n\nOr, are you asking how much would you have today if you had put 5 shillings into an interest bearing account in 1659?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
g6k4t
|
How can I determine the frequency of a ray of colored light?
|
Hello everyone. I want to determine the frequency of a ray of colored light. The visible light spectrum is about 405 THz to 790 THz, so if I take a red beam of light and shine it, I want to know that its frequency is ~700 THz.
Example of what I'm looking for - a sensor that, when light is shone on it, will output an electric signal that is the same frequency (or orders of magnitude lower).
If I'd need to design & build this from scratch, what sort of resources would I need?
|
askscience
|
http://www.reddit.com/r/askscience/comments/g6k4t/how_can_i_determine_the_frequency_of_a_ray_of/
|
{
"a_id": [
"c1l9mao",
"c1l9xoc"
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3,
3
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"text": [
"Depending on the accuracy you require, you could also have a linear sensor and a prism. The prism will bend the light by an amount predictably related to the wavelength, meaning that different frequencies will be deflected to a different spot on the sensor.\n\n[Here](_URL_0_) is a very inaccurate but helpful diagram.",
"Look up designs for spectrometers, there are plenty of different approaches to it. Some sort of prism or a grate would probably be needed, a couple of lenses and mirrors and ideally a linear CCD hooked up to a computer, which you need to calibrate at first. This is going to give you the wavelength, speed of light divided by wavelength gives you the frequency.\r\n\r\nedit: [This would be a simple setup](_URL_1_).\r\n\r\nYou can also buy them premade obviously, I have worked with [this one](_URL_0_) before."
]
}
|
[] |
[] |
[
[
"http://imgur.com/elTlq"
],
[
"http://www.oceanoptics.com/Products/usb2000.asp",
"http://images-mediawiki-sites.thefullwiki.org/04/3/7/0/37449961459457742.gif"
]
] |
|
1o2787
|
How and why exactly was the technology of the Roman Empire lost to the rest of the world in the period of the Late Antiquity
|
Me and a friend at work had a discussion yesterday and it intrigued me. Rome had influence on areas that would later become places like France, Germany and even Britain.
They could make concrete structures like the coliseum which is of better quality than todays Concrete. They had indoor plumbing ..
They did things that are just now catching on today like radiant heating , by flowing heated water under their floors or simply heating hollow air spaces under the floor.
They had Glass windows.
Yet when rome fell and we went through the late antiquity with centuries of "Stone" castles with no glass, and heavy tapestries to keep in heat. Inefficient furnaces and fireplaces and pestulence and cold and overall societal collapse.
Either they were unwilling, or unable to use these technologies. I cannot believe everyone who knew about them "died". So they must have been able, therefore they had to be unwilling. And this period is marked by religious oppression and turmoil.
My theory was that Rome was a symbol of depravity and religious beliefs may have led people to believe we must forge our own new path and anything associated with the Rome and thus "spiritual decay" was avoided.
But even so ..if you are "able" and unwilling. Seeing your children dying of pestulance, unsanitary conditions ..and cold. There were simple solutions people should have remembered and passed on to others. Unless they felt suffering was part of "God given existence" stranger things have been done in the name of faith.
Was it economic? due to beliefs? or did all this knowledge really just .."go away" Rome was more than just its empire, it influenced people and occupied places far and wide.. I cannot accept the fact no one "remembered" that "Burning that waste straw in a hollow space under my floor is a good way to keep from getting sick in the winter". But brick would be expensive, stone would be expensive. you would need stone structures to safely use this heat. But why not teach more people to make brick? too costly to pay them?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1o2787/how_and_why_exactly_was_the_technology_of_the/
|
{
"a_id": [
"cco6w7g"
],
"score": [
6
],
"text": [
"What you're referring to is the Dark Age theory, which doesn't really hold much sway anymore. I'm sure if you dig around the popular question section you'll find some other in depth posts about this issue, but I'll sum some of it up here:\n\nBasically, when the Western Roman Empire \"fell\" (this is also up for discussion, but whatever) and in the time before and after it, western Europe was going through a lot of drastic changes. Not in the least the great migrations, but also an increasing ruralisation and the move from a centralised system to a decentralised system. None of these changes were a step back per se, they were just different. \n\nBut with all these changes came different needs - aqueducts become less important when cities depopulate, for instance. Building an aqueduct for a village is just excessive and unnecessary. Same thing with most forms of plumbing - these were things that were necessary to keep large cities like Rome habitable, but they become less urgent if these cities decrease in population. \n\nAnother important factor was the changes in long distance trade. Trade didn't collapse with the empire, obviously, but did end up changing with the society of the time. Local resources became more important. So when you compare the Colosseum with a Medieval castle, you're being a bit unfair. The Colosseum was built with Travertine stones (not concrete) which were easily produced in Italy. The castles you're probably talking about are most likely in the more northern areas of Europe (areas which Rome barely had any control over, by the way, if any) - are they really going to import thousands of stones from Italy or other far away quarries or are they going to use the more locally abundant natural stones? I'm pretty sure the Romans used these natural stones too when they built things in those areas. I'd like to remind you that stone buildings weren't common, even in the Empire. Most of Rome was full of wooden buildings, after all. Only the villas of the richer families were built from types of stone. So there's little difference between the common man in Roman days and afterwards. \n\nAnd about disease: the link between sanitation, hygiene and health was only popularised in the 19th century. The Romans didn't build their plumbing to keep their populace healthy, they did it to keep the streets from overflowing with shit. Nobody during the Roman Empire and afterwards really had a solid grasp on why people kept getting sick until the late 19th century, really. \n\nA lot of the knowledge of the Roman Empire simply wasn't lost. It was either preserved locally - the things that mattered and could be used in their conditions (reminder that people in those days were very practical about technology - if you couldn't use it, it wasn't really worth remembering) -, copied and preserved by monks or exported via the Eastern Roman Empire to the Arabs. Hope that answers at least part of your question."
]
}
|
[] |
[] |
[
[]
] |
|
2raj77
|
what does goldman sachs have to do with the eurozone and why do they seem to be such a big player in it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2raj77/eli5_what_does_goldman_sachs_have_to_do_with_the/
|
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"text": [
"Last I checked, an ex Goldman Sachs employee ran the European Central bank. So that's fairly significant.",
"Basically, Goldman Sachs helped to mask greeces debt.\n\n_URL_0_",
"Goldam Sachs are big investment bank. So they have investments in multiple countries in Europe, The problem with Europe is most countries have serious debts / or need money to run the country. So they use Banks like Goldam Sachs to borrow money which cause them to have power! Money = power in politics :)",
"Goldman Sachs is known for its deep connections to politics. This is true not just in Europe, but very much in the United States as well. Many powerful decision makers have been employed by Goldman Sachs.\n\nIt may also be that Goldman Sachs have a strategy of working with governments. Since they are probably the worlds largest investment bank, they may be able to do some deals (loans to governments) that are to large for other banks.\n\nThat said, I'm not sure that Goldman Sachs really is such a 'big player' in the Eurozone, it is after all an American investment bank. Large European investment banks, like Credit Suisse, Deutsche Bank or BNP Paribas may very well be bigger players in the Eurozone specifically.\n\nIt is possible Goldman Sachs have received more attention just because they are from outside of Europe, are the biggest and are previously known for shady deals."
]
}
|
[] |
[] |
[
[],
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"http://www.spiegel.de/international/europe/greek-debt-crisis-how-goldman-sachs-helped-greece-to-mask-its-true-debt-a-676634.html"
],
[],
[]
] |
||
3inl4f
|
why does putting a spoon in the top of a bottle champagne, bear ect. keep the fiz in the bottle even over night
|
a friend told me about this. it worked. and now im just confused and have more questions than i thought i would have for asking how to keep a beer from going flat.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3inl4f/eli5why_does_putting_a_spoon_in_the_top_of_a/
|
{
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"cuhzzwd",
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],
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3
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"text": [
"It doesn't. Sparkling wine keeps its fizz for longer than most people realise so the spoon trick appears to work even though it has no effect b",
"1. The spoon in champagne theory has not really been confirmed scientifically.\n2. To keep a beer from going flat you should drink it faster!"
]
}
|
[] |
[] |
[
[],
[]
] |
|
47k2x0
|
are there accounting and investor-related benefits to hiring contractors instead of employees?
|
Not interested in the employee cost savings, which has been covered in previous posts. But more the accounting and investing reporting reasons why having less headcount and more contractors would be beneficial to a large company.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/47k2x0/eli5_are_there_accounting_and_investorrelated/
|
{
"a_id": [
"d0dhnrj"
],
"score": [
2
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"text": [
"Depending how contractors are paid, there could be a cash flow benefit. Most employees expect regular payments. Many contacts are set up in such a way that much of the payment is deferred to the completion date. "
]
}
|
[] |
[] |
[
[]
] |
|
4gvvp9
|
can blind people see light?
|
I mean... when you look at the sun, you look away because it is too bright. Do blind people have the same reaction as well?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4gvvp9/eli5can_blind_people_see_light/
|
{
"a_id": [
"d2l5sar"
],
"score": [
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],
"text": [
"It depends on how blind they are (there are degrees of blindness). Some people can see light/dark or shadows, some can see certain areas of their vision but not others, some can't see anything at all, so the answer is both yes and no."
]
}
|
[] |
[] |
[
[]
] |
|
d0ng4e
|
AskHistorians Episode 140 - The International Brigades in the Spanish Civil War
|
[**Episode 140 is up!**](_URL_8_)
The [AskHistorians Podcast](_URL_10_) is a project that highlights the users and answers that have helped make r/AskHistorians one of the largest history discussion forums on the internet. You can subscribe to us via [iTunes](_URL_9_), [Stitcher](_URL_7_), or [RSS](_URL_5_), and now on [YouTube](_URL_3_) and [Google Play](_URL_6_). You can also catch the latest episodes on [SoundCloud](_URL_2_). If there is another index you'd like the cast listed on, let me know!
**This Episode:**
Today we're joined by Fraser Raeburn, our very own /u/Crrpit, to talk about the International Brigades during the Spanish Civil War with a specific emphasis on Scottish volunteers. Who joined? Why did they join? What were the politics of the International Brigades? Hear about this, and much more, in this episode.
Make sure to read Fraser's recently published scholarly article, *Politics, Networks and Community: Recruitment for the International Brigades Reassessed* in the [Journal of Contemporary History](_URL_0_). You can find him on Twitter as @FraserRaeburn.
**Questions? Comments?**
If you want more specific recommendations for sources or have any follow-up questions, feel free to ask them here! Also feel free to leave any feedback on the format and so on.
If you like the podcast, please rate and review us on [iTunes](_URL_9_).
Thanks all!
[Previous episode and discussion.](_URL_1_)
**Next Episode:** /u/MimicofModes is joined by Lyndsey Craig!
Want to support the Podcast? Help keep history interesting through the [AskHistorians Patreon](_URL_4_).
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/d0ng4e/askhistorians_episode_140_the_international/
|
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"https://www.reddit.com/r/AskHistorians/comments/c3ihzz/askhistorians_episode_139_bibliography_of_the/",
"https://soundcloud.com/user679855208",
"https://www.youtube.com/channel/UCJudPwztZyg2BQjhetw_bww",
"https://www.patreon.com/askhistorians",
"http://askhistorians.libsyn.com/rss",
"https://play.google.com/music/podcasts/portal#p:id=playpodcast/series&a=100831514",
"http://www.stitcher.com/podcast/tas-stacey/the-askhistorians-podcast",
"http://askhistorians.libsyn.com/-askhistorians-episode-140-the-international-brigades-in-the-spanish-civil-war",
"https://itunes.apple.com/us/podcast/the-askhistorians-podcast/id812302476?mt=2&ign-mpt=uo%3D8",
"http://askhistorians.libsyn.com/"
] |
[
[]
] |
|
8s2g3u
|
Why doesn't a moving massive object within a black hole's event horizon affect the gravitational force of the black hole (including said object) felt by observers outside the event horizon?
|
Consider Alice, drifting just outside the event horizon, and Bob, located 1 meter away, just inside the event horizon. As Bob starts drifting towards the center of the black hole, the distance between him and Alice increases and one would think that the gravitational force experienced by Alice (caused by Bob and the black hole) should decrease. But obviously this can't be the case since no information can escape the event horizon. But how should one think in order to understand this? Is there even a simple way to describe why this cannot be so? A related question: does the gravitational force of a black hole behave as if all mass contained within the event horizon was located at the center of the black hole?
|
askscience
|
https://www.reddit.com/r/askscience/comments/8s2g3u/why_doesnt_a_moving_massive_object_within_a_black/
|
{
"a_id": [
"e0wnsh7"
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"text": [
"Hi, so, I hate to say it, but the other answers here are wrong, and so is your assumption: you absolutely would continue to detect the modified field as an object plummets to the singularity.\n\nBefore we dive in, let me ask you three questions:\n1. In the famous LIGO initial detection of gravitational waves from two colliding black holes, how did those waves get out from the colliding singularities if those singularities were always cloaked in event horizons?\n2. A charged black hole still exerts an electric field on the surrounding space. If all the charge is in the singularity, how does an electron travelling outside the event horizon \"know\" to respond to the charge?\n3. For that matter, if all the mass is in the singularity and cloaked by an event horizon, how does a passing mass know to react to it? How does the gravity \"get out\"?\n\nThe answer to all these questions, and to your question, is we can still detect gravitational waves, charge, and gravitational forces, because they're not coming from inside the event horizon. The waves, the charge, the force from the black hole and the force from infalling matter are all contained in the fields themselves which exist above the event horizon. \n\nFields have reality of their own, and exist at each point in space regardless of the \"source\". The forces affecting a particle are local and part of the local field. And so the gravitational field of the infalling object exists in those points of space above the horizon independently of whether the object has passed the event horizon or not.\n\nNow as a bonus question: can that field be used to track the object inside as it moves around? Can you have a ship fall in, then agree to turn on it's engines one way if it sees X inside the horizon, and the other way if it sees not(X), and then measure the field outside the horizon to see which happened? No, you cannot - the field outside a black hole can't be affected by the behavior of the infalling spaceship because that region of space can't communicate with the outside. The gravitational field outside the horizon will behave as if the infalling object continued to fall directly to the singularity.\n\nThis ability to distinguish the gravtitational field of an infalling object after it passes the event horizon doesn't violate the no-hair theorem, because the no-hair theorem applies to systems with a single mass (the singularity). In these cases, the surrounding spacetime can be described knowing only the mass, charge, and angular momentum. A system of masses which include multiple objects, such as a black hole and another infalling object? Such a system would not be in the scope of the theorem."
]
}
|
[] |
[] |
[
[]
] |
|
1wcfnp
|
Recommended Reading For the Dutch Golden Age?
|
I did not see anything in the book list, apologies if I missed it.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1wcfnp/recommended_reading_for_the_dutch_golden_age/
|
{
"a_id": [
"cf1c4ud"
],
"score": [
3
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"text": [
"Are there any particular areas you're interested in?\n\nFor a hefty general text, Jonathan Israel's 'The Dutch Republic: Its Rise, Greatness and Fall' is worth a read.\n\nA good politically-focused book is Maarten Prak's 'The Dutch Republic in the 17th Century'.\n\nFor the Dutch economy, Jan de Vries is particularly good, as is van Zanden. A lot of de Vries' writings are on Europe as a whole, but they still tend to focus primarily on the Dutch Republic, and so are worth looking at.\n\nFor a social history, Van Deursen's 'Plain Lives in a Golden Age' provides plenty of interesting discussion of how much there was a \"trickle down\" of wealth as a result of the Dutch Republic's commercial success.\n\nIf it's art that particularly interests you, Christopher Brown's 'Dutch Painting' is a nice introduction, whilst Wayne Franits' 'Dutch 17th Century Genre Painting' provides a longer, more detailed discussion of the distinctive schools of Dutch painting."
]
}
|
[] |
[] |
[
[]
] |
|
721ywa
|
how can a cable possibly be stretched across the entire atlantic ocean?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/721ywa/eli5_how_can_a_cable_possibly_be_stretched_across/
|
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"text": [
"Very long cables, carried out on large vessels. They lay on the ocean floor where they dont see too much marine life. Even so, they have a thick casing to guard against animal curiousity. ",
"Undersea cables are large and very well protected from the elements. Animals aren't a major concern. The ocean is miles deep, but that isn't really a problem. Cables aren't placed by divers or submarines, their unspooled off the back of a big ship.",
"Its really long and sits on the bottom. Its pretty well protected and its uninteresting to animals. They're as inclined to destroy it as the Titanic, its just an uninteresting hunk on the bottom.\n\nThe cable isn't really *stretched* across the Atlantic, its just laid out on the ocean floor by a ship with a really really long spool of special cable",
"Neal Stephenson wrote a cool article about the internet infrastructure that included a big section on putting down an ocean cable: _URL_0_\n\nSearch for \"ocean\" and it was the second hit that was in the section of interest, I think. The whole thing is very interesting, but long :)\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://www.wired.com/1996/12/ffglass/"
]
] |
|
atmzhx
|
Why do many Gaulish Names end in -ix?
|
I assume that this is not entirely true to the degree that it is in *Asterix*, but many names of famous people in the Gaulish times of Caesar ended in -ix, such as Vercingetorix, Dumnorix, and Orgetorix. Was it just a common suffix, or was it some sort of honor given to a leader?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/atmzhx/why_do_many_gaulish_names_end_in_ix/
|
{
"a_id": [
"eh25jg8"
],
"score": [
3
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"text": [
"/u/Astrogator answered this [here](_URL_0_)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/7d0bqr/is_the_common_suffix_ix_on_the_end_of_gallic/"
]
] |
|
4fonzq
|
the uk investigatory powers bill
|
What exactly is it? And how exactly does it affect technology users in the UK?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4fonzq/eli5the_uk_investigatory_powers_bill/
|
{
"a_id": [
"d2an6zp"
],
"score": [
5
],
"text": [
"It's a bill to allow the government to retain the browsing history of everybody in the UK for at least a year, without suspicion or probable cause.\n\nIt's being championed by Theresa May, someone who is demonstrably incompetent and also the queen mother of godawful, totalitarian-sounding legislation. The sweeping powers she's gunning for are completely disproportionate to the threat they're intended to counter, and according to privacy experts will actually make it *harder* for the authorities to pursue useful leads, by making the haystack in which they are searching for needles orders of magnitude larger. She even defended the principle of making the haystack bigger.\n\nNeedless to say the whole thing is draconian and creepy, and even if it isn't really being used to monitor dissent and anti-government sentiment, there's no saying that it won't ultimately be used for that, as frequently happens with these kinds of powers.\n\nIncidentally, Theresa May and Satan have never been seen together in the same room.\n\nEdit: snarkification"
]
}
|
[] |
[] |
[
[]
] |
|
2efdek
|
What is the difference between blood pressure and peripheral vascular resistance?
|
Hi guys, I know this seems like a pretty basic question but it's tying me up in knots - can anyone help explain this to me? Thanks!
|
askscience
|
http://www.reddit.com/r/askscience/comments/2efdek/what_is_the_difference_between_blood_pressure_and/
|
{
"a_id": [
"cjyzjwu",
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2
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"text": [
"Blood pressure (mean) = cardiac output (amount of blood pumped over time) x peripheral vascular resistance.\n\nCardiac output = stroke volume of each heart beat * heart rate.\n\nSo BP will increase with PVR but PVR isn't the only factor. ",
"Trying to explain this conceptually. Resistance is the opposite of conductivity. Physically resistance is the friction caused by the walls of the blood vessels, especially the peripheral vascular system. The longer the vessel, the higher the resistance; the smaller the radius of a vessel, the higher the resistance. This is known as Hagen-Poiseuilles law (and includes other factors such as viscosity of the liquid, but that should be the gist of it). Note though that with the rapidly increasing crosssectional area of the capillary system kirchhoffs laws set in (parallel conductors lead to higher conductivity/lower resistance), so this phenomenon pertains to small arteries and arterioles.\n\nPressure is what builds up when a flowing fluid (defined by its flow rate, eg volume / time) meets resistance. Following thought experiment: you have a thick straw and you are blowing a liquid through it. As expected you experience no trouble in doing so. Now imaging pinching the straw in the middle a bit. What happens is that it gets increasingly harder to blow the fluid through the straw, you can ¨feel¨ it accumulating in the top part (high pressure) while there is not a lot of actual fluid ending up in the bottom section (low pressure). (yeah yeah I know, bernoulli effect and turbulence play a role, lets just say we are not dealing with turbulence right now) Now do not forget what pressure stands for: either force over area or (in this case preferentially) energy over volume, or the amount of energy ¨stored¨ in any given volume of fluid. Now of course this means we need a force (or source of energy) to work with - as /u/Henipah indicated this is provided by the cardiac ouput, eg the cardiac output (the volume of blood pumped by the heart at a given amount of time) is the driving force behind building up blood pressure with the addition of the high overall resistance of the peripheral vascular system causing the blood to be partially ¨blocked¨ (note that the pressure in the following venose system is pretty low, remember how that was in the straw experiment).\n\nNow there are a lot of other cool mechanisms of up- and downregulating blood pressure, for example the aorta acting like an air chamber (elastically widening due to the high pressure caused by the immediate cardiac output, causing an increase in volume and thus decrease in systolic blood pressure, while contraction of the aorta during the diastole causes a slow decrease of volume, thus higher and more stable blood pressure during diastole), contraction of the smooth muscles of the peripheral vascular system (decreasing radius, thus increasing resistance, thus increasing arterial blood pressure; dilation does vice versa), opening ¨dormant¨ anastomoses (kirchhoffs laws as aforementioned) and probably a lot more I forgot about."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3mgr04
|
Was the "Southern Strategy" during the U.S. civil rights movement a real thing or a myth?
|
Contemporary republicans and conservatives will often swear up and down that the southern strategy is a myth, claiming that liberals are and always have been responsible for most of the racism in this country. They then usually cite the fact that Lincoln was a republican. So was the southern strategy real or a myth?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3mgr04/was_the_southern_strategy_during_the_us_civil/
|
{
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"text": [
"Not to discourage conversation here, but the FAQ has several good [threads](_URL_1_) on this topic, including several great answers from /u/Samuel_Gompers [here](_URL_2_) and [here](_URL_0_).",
"What was the southern strategy?"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/12vvo4/how_and_when_did_the_republican_party_transition/",
"https://www.reddit.com/r/AskHistorians/wiki/us_history#wiki_changing_role_of_republicans_and_democrats",
"https://www.reddit.com/r/AskHistorians/comments/yczua/can_someone_address_a_brief_history_of_democrats/c5ui4pm"
],
[]
] |
|
5b2bpj
|
why do we consider electric cars "green" if we need fossil fuel to produce electricity ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5b2bpj/eli5_why_do_we_consider_electric_cars_green_if_we/
|
{
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"text": [
"There are other ways to produce electricity - solar, wind, hydro, nuclear.\n\nAdditionally, even fossil-fuel power plants are more efficient than an internal combustion engine, and they also produce less polluting gasses (relative to the amount of energy they produce).",
"The electric vehicles are considered 'green' because they have no emissions. The problem relies in how electricity is produced, not the car. Many countries have already achieved > 90% renewable electricity.",
"Right now tehnically there is a conflict like you said, but as many more countries implmement renewable energy initiatives before long there won't be any conflict anymore cause the energy source will be green as well. Also Elon Musk is in the solar power industry and they are planning to integrate that technology to Tesla which will accelerate the \"green-ness\" of their electric cars, hopefully others will follow.",
"Because big electrical generation plants are better at burning fuel for power than cars are.\nThey have special machines to get every bit of energy from the fuel where as a car has a small engine that has to be portable and wastes lots of the energy ",
"They are marketed as \"green\" because they do not directly produce greenhouse gasses. If, however, you live in an area that uses fossil fuels to produce electricity then the electric car isn't really as \"green\" as advertised as it is still burning its fair share of carbon fuel, just through secondary means.\n\nA more troubling aspect of electric cars are the rare elements required to construct them. The mining and processing of these rare elements can be very destructive to the environment.\n\nI think electric cars are better for the environment, overall, compared to traditional combustion vehicles, but there is a fair amount of miss information surrounding the electric car fad.",
"Gas powered vehicles roam around, emitting pollution all over. This is called \"non-point source pollution.\" Coal-fired electric plants are in one place, and the towers that emit vapor have \"scrubbers\" that scrub the air, much like the cabin air filter in your car or the air filter for your HVAC system in your house. It is much easier and more efficient to control air emissions at one point than many, especially mobile sources. Therefore, regardless if the electricity comes from a renewable source (wind, solar) or a non-renewable source (coal, natural gas), there are zero emissions from cars driving all around. Therefore, electric cars are \"greener\" than cars powered by fossil fuels since the pollution source is in one place (point-source emission) instead of multiple places (non-point source pollution)."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
||
qmg6j
|
why the prices of milk are like this (pic inside)
|
At my local Walmart, the prices of milk have been weird for the last 3 months. It used to be for 2% milk, the prices for gallons and half gallons were [$2.43 for a half gallon, and $2.39 for a full gallon.](_URL_1_) At first I thought something along the lines of "Well, they must have gotten a lot more full gallons in this shipment and are trying to push them out before they go bad." This was also accompanied by the fact that 1% milk and whole milk were normal (Relatively-- the gallon was about 7 and 14 cents, respectively, higher than their half gallon counterparts). But the price stayed at that point for **three months**.
Today, I go to Walmart for milk and find this: [$2.36 for half gallon, $1.99 for full gallon.](_URL_0_) Crazy! And to top it off, the prices for 1% and whole milk have gone this way as well (With the full gallon being lower priced than the half). Why are they priced this way? If it matters, this Walmart I go to is in a very low-income area, maybe there's governmental incentives at play? What's going on here?
EDIT: This isn't about paying less per unit for items in bulk. That's understandable and common. This is about **paying more money for less product**.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/qmg6j/eli5_why_the_prices_of_milk_are_like_this_pic/
|
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"text": [
"Relate it to Coke bottles:\n20oz bottle: $1.50\n-Easy to carry and drink quickly\n-Fit in cup holders\n-Convenient\n-Good for on the go\n\n68oz (2liters): $1.09\n-Large, bulky\n-Unconventional for casual drinking\n-Better for taking home\nBoth of the bottles have the same product, but the have different markets, or who they are selling to. \n\nSame goes for milk, the smaller milk is better for a person who isn't looking to get a lot of milk, while the larger milk is probably for a family that consumes a generous amount of milk per week. \nRemember, things are cheaper in bulk, the more you buy, the less you pay per item. \n",
"That's some cheap fucking milk",
"Did you look at the expiration date? \n\nThe $1.99 milk was probably about a couple days before expiring. So they knocked the price down. Which entices people to buy it up. Because if they put a \"Sale\" sticker on dairy....people would automatically know \"ew, that milk is old. I'm not buying it.\" But without the sale sicker then they think \"fuck yeah, there must have been too much made so it's cheap.\"\n\nThis is what my local chain grocery store does.",
"My guess is that enough people will actually pay extra for the smaller, more-conveniently-sized container. Yeah, you would pay less for the larger container (not just per ounce, but for the whole thing), but maybe you just don't want that larger container for whatever reason - because it's too big for your dorm room fridge or you just want some for lunch and you don't want to deal with a \"giant\" gallon jug, etc.\n\nI am not explaining from experience, by the way. I would totally not be able to pay the greater price for the smaller volume (it would just feel so wrong), but I can see how some people might. I can even see how there might be enough such people that the supply demand equation would make the prices go the way they appear to have gone in the OP's description."
]
}
|
[] |
[
"http://imgur.com/a/rqzOm#1",
"http://imgur.com/a/rqzOm#0"
] |
[
[],
[],
[],
[]
] |
|
2euh4b
|
Why does a cigarette's paper burn through fast when its empty but slow when there's tobacco inside?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2euh4b/why_does_a_cigarettes_paper_burn_through_fast/
|
{
"a_id": [
"ck32lq0"
],
"score": [
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"text": [
"Increased airflow. When it is filled with tobacco, there is not a lot of air (and so oxygen) *inside* the cigarette (because its stuffed with tobacco). Less oxygen results in a slower burn. \n\nWhen there is no tobacco whats there instead is air. This means a fast burn.\n\nThe reason a cigarette burns faster when you take a 'puff' is because you are effectively 'sucking' air through the cigarette, which momentarily increases oxygen and speeds up the burn. "
]
}
|
[] |
[] |
[
[]
] |
||
21tiua
|
"Every star you see in the night sky is bigger and brighter than our sun." Is this true?
|
I've read this a few days ago and I can't seem to find any sources behind this statement, so is this true? Especially this with brightness?
EDIT: Of course, without telescope.
**EDIT2: Thank you guys, I now know not to take 'mind-blowing facts' from internets seriously.**
|
askscience
|
http://www.reddit.com/r/askscience/comments/21tiua/every_star_you_see_in_the_night_sky_is_bigger_and/
|
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"text": [
"I'm not sure if this counts because it's a binary star system, but [Alpha Centauri B](_URL_0_) is a bit smaller and less luminous than the Sun, but Alpha Centauri A is a bit bigger and brighter than the Sun. With just the naked eye it appears as one object, though.",
"No, Epsilon eridani has 82% the mass and a third the luminosity of the sun. Tau ceti has 78% the mass and half the luminosity of the sun. Both of them are visible to the naked eye. I'm sure there are many more examples, but those are the only two I know about off the top of my head.",
"This is not true, you can see [ε Eri](_URL_1_) for example, with naked eye, which is smaller than the Sun in both size and mass.\n\nYou can read more about stellar classification [here](_URL_0_). The Sun is a yellow dwarf, there are other yellow dwarfs we can see with naked eye that are smaller, and also some red dwarfs.",
"Stars fit into different categories, known as \"spectral classes\". This is because the mass of a star determines the pressure inside it, which determines the types and rates of nuclear fusion processes that can occur inside it. This in turn determines the temperature of the star. Depending on its temperature, we will see different features in its light so we can tell what class of star it is from Earth.\n\nThe classification system goes in the following order: O B A F G K M, where \"O\" stars are the heaviest, brightest, shortest-lived stars and \"M\" stars are the coolest, smallest and longest-lived. It's also worth noting that there are many more small stars than there are big ones. Our sun is a perfectly ordinary \"G\"-type star, so there are stars out there that are bigger and brighter than our sun and plenty more that are smaller and fainter.\n\nAn added complication is that stars change in brightness over time, particularly towards the end of their lives when they can swell up to many, many times their original sizes.\n\nOf course, how bright they appear from Earth depends on how far away they are as well as their intrinsic brightness. I hope this helps.\n\n(Source: I'd recommend reading the Wikipedia pages on [stellar evolution](_URL_0_) and perhaps [spectral types](_URL_1_) if you would like some more information. The pages contain many links to further sources of information too.)\n\n(This is my very first post on reddit!)",
"The Sun or otherwise known by it's Latin name \"Sol\" (hence Solar System) is a main sequence star with a classification of G.\n\n\n-G-type stars can be also known as \"Yellow Dwarfs\" (you heard that right, our star is smaller than most) Such a star has about 0.8 to 1.2 solar masses, and operates at roughly 5,000 - 6,000 degrees k. \n\n\n-One of the key measurements when classifying a star is called solar luminosity, this measurement figures in the amount of energy the photons carry away from the star, aside from how luminous the star is, this measurement can also be used to determine the age, stage, and life span the star will have when used in conjunction with other numbers. Basically, how bright the star is, that said, Sol has a low luminosity compared to many larger, hotter, younger stars.\n\nThis compares luminosity between some stars: _URL_2_\n\nOther stars that you can see in the sky with a similar classification of G:\n \n\n61 Virginis - _URL_0_\n\n\n47 Ursae Majoris - _URL_4_\n\n\n HD 102365 - _URL_1_\n\n\nThose are not star names you remember Im sure.... anyone you can see will most likely be significantly brighter, or a galaxy and not a star.\n\n\n\n\n\n\n\n\n\n---------------------\nEdit: something worth noting: Compare HD 102365 - _URL_1_ with Deneb - _URL_3_. Deneb is roughly 2600 light years away, which is 86.6 times futher than HD 102365, (I choose that star because it is very similar to Sol) and yet, Deneb is one of the brightest stars in the sky.... eighty six and two thirds times further, and yet still brighter... something to think about.\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Alpha_Centauri"
],
[],
[
"http://en.wikipedia.org/wiki/Stellar_classification#Harvard_spectral_classification",
"http://en.wikipedia.org/wiki/Epsilon_Eridani"
],
[
"http://en.wikipedia.org/wiki/Stellar_evolution",
"http://en.wikipedia.org/wiki/Stellar_classification#Spectral_types"
],
[
"http://en.wikipedia.org/wiki/61_Virginis",
"http://en.wikipedia.org/wiki/HD_102365",
"http://upload.wikimedia.org/wikipedia/commons/1/17/Hertzsprung-Russel_StarData.png",
"http://en.wikipedia.org/wiki/Deneb",
"http://en.wikipedia.org/wiki/47_Ursae_Majoris"
]
] |
|
4b4e9y
|
Did the Nazis ever release English-language propaganda, or attempt to appeal to English-language media as it became obvious a greater rift was growing between them and UK/USA/Canada/etc?
|
I guess I'm mainly referring to pre-war, but stuff during the war is absolutely fine too.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4b4e9y/did_the_nazis_ever_release_englishlanguage/
|
{
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"text": [
"There were a couple English-language propagandists. William Joyce, aka Lord Haw Haw, is likely the most well-known. He would broadcast English-language propaganda from Berlin to London airwaves from 1939 until his capture in 1945. [The BBC actually has several of his broadcasts available online](_URL_2_)\n\nReference: [Nazi Wireless Propaganda: Lord Haw Haw and British Public Opinion in the Second World War](_URL_1_)\n\nOther broadcasters of English-language Nazi propaganda include [Mildred Gillars (Axis Sally) and Fred W. Kaltenbach (Lord Hee Haw)](_URL_0_)\n\nI am not an expert, but I have studied WWII and the Holocaust. I've provided references, but Mods, if this still doesn't fit the rules, please feel free to remove."
]
}
|
[] |
[] |
[
[
"http://www.history.com/news/history-lists/6-world-war-ii-propaganda-broadcasters",
"https://books.google.com/books?id=nvRNx6YM7LIC&lpg=PP1&dq=Lord%20Haw%20Haw&pg=PP1#v=onepage&q=Lord%20Haw%20Haw&f=false",
"http://www.bbc.co.uk/archive/hawhaw/index.shtml"
]
] |
|
40cp4o
|
what does "safely remove hardware and eject media" do to make it "safe"?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/40cp4o/eli5_what_does_safely_remove_hardware_and_eject/
|
{
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"It prevents the computer from trying to write to the media while it is being physically removed. If it's removed while the computer it trying to write to it, it can damage all the data on the disc.",
"Some applications are constantly producing data that they write to a file. If one of those is running then you tell it to stop what it was doing so that you don't get a half-written file.\n\nAlso, writing to a file is a fairly expensive operation, so many programs will save up data and then write it all at once. This minimizes the overhead of writing to the file. \"Safely Remove\" tells these programs to go ahead and write whatever they've saved up.\n\nFinally, many drives have a bit of really fast memory so that when a program *does* decide to write to the drive they can just transfer the data to that memory and then the drive can sit there and slowly transfer it to the actual long-term storage memory on the device (the really fast stuff needs constant power to remember what it's storing). \"Safely Remove\" waits for this memory to all be written to the long-term memory of the drive.\n\nIn many cases \"Safely Remove\" won't actually be able to tell all the programs to finish what they're doing, but it can at least tell you that there are still things using the drive so that you don't pull it out and wind up with half-written files corrupting the drive. ",
"To bring this back to ELI5's real roots, here's an analogy: Pretend you're a 5 year old coloring a picture of an adorable kitty. Now you mother comes over and grabs the paper and pulls it, while you were still coloring. The crayon is still in your hand, and still touching the paper, so if she pulls hard, it'll make a line that totally ruins your artistic vision.\n The \"safely remove\" feature just tells the computer to wait until there's no coloring going on before yanking the paper away.\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3scj0j
|
what is end-to-end encryption that everybody is talking about with regards to the uk and how does passing that bill to end it effectively be a bad thing?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3scj0j/eli5_what_is_endtoend_encryption_that_everybody/
|
{
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"text": [
"End to end encryption means that the data get encrypted before it is ever transmitted, and not decrypted until after it is received on the other end. This is the only way to guarantee that it's protected from somebody listening in somewhere in between. \n\nThe UK government would very much like to listen in to peoples' conversations. People who believe in privacy would very much like to prevent that. "
]
}
|
[] |
[] |
[
[]
] |
||
2q3quu
|
How do I know if what I'm looking at is a star or a galaxy?
|
Like in general on a dark clear night, is there a way to differentiate between the two just with the naked eye?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2q3quu/how_do_i_know_if_what_im_looking_at_is_a_star_or/
|
{
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"text": [
"There are only a few galaxies you can see with your naked eye. Andromeda (M31) and the Magellanic Clouds being the only ones a typical untrained observer will ever see or notice. All three are fuzzy blobs of varying size. It is possible to confuse a galaxy with a nebula like the Orion Nebula (M42) or globular cluster like Omega Centauri which also appears as a fuzzy object but individual stars are always just points of light. Stars don't have width and fuzzy edges unless seeing conditions are pretty bad."
]
}
|
[] |
[] |
[
[]
] |
|
5xw0af
|
if transubstantiation means the body of christ is being eaten, doesn't that mean it's cannibalism?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5xw0af/eli5_if_transubstantiation_means_the_body_of/
|
{
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"text": [
"Not exactly. Denominations that believe in transubstantiation also don't think that Christ was merely human, but in fact the son of God. This includes the belief that he is *consubstantial*, that is, made of the same essence, as God the father. The typical idea of cannibalism doesn't really apply to that situation."
]
}
|
[] |
[] |
[
[]
] |
||
eyh4z4
|
why, in todays high tech age, do we still use film stock and lenses for movies and pictures, when it could all be done on a computer?
|
People spend tens of thousands on anamorphic lenses and such, when you could just film in 4K, add a lens flair filter, and crop it to desired ratio. Clearly im missing something
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/eyh4z4/eli5_why_in_todays_high_tech_age_do_we_still_use/
|
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"text": [
"Many people feel that using traditional filming methods makes the movies look better, as they prefer the way images appear when filming on film stock rather than going digital. Enough directors and cinematographers feel that way that a decent amount of films are done on film stock even today, despite it being more expensive.",
"For the same reason professional musicians record onto tape; film and tape actually have practically infinite resolution, whereas converting recorded information into the digital realm is always limited by the current technology’s resolution capabilities, thus there’s is always something lost. \n\nSome might argue that what is lost in high end digital is imperceptible to the human senses, but others argue that there’s just a “certain something” that happens with film and tape that can’t be reproduced digitally for this very reason.",
"Despite the standard of digital sensors, film still has the advantage in some areas. You can massively over-expose film and still see some details, where digital will just give you solid whites. It's the other way around at the dark end. Some people still prefer film.\n\nBut you talk about lenses too! Those are used for both film and digital sensors. I don't see an alternative unless you're proposing rendering everything with CGI. Good as computer rendering is today, it's still not on the level of real-world footage. More to the point, it's massively more expensive.\n\nYes, I wish they'd dump anamorphic lenses for everything. Not only is all the flare and bokeh weird, but they breathe in such a strange way, with focus pulls causing the aspect ratio to change.",
"Lenses and film are two separate issues.\n\nI am no sure of the exact difference between the quality of capturing on film and digital and what advantages there are. But for expensive lenses, there is a huge difference\n\nIf you capture an image with a regular lens and an anamorphic the bokeh is quite different. The bokeh is how out of focus stuff looks. An out of focus light on a regular lens is circular but on anamorphic the are oval. [Compare it here](_URL_2_). \nThere is no easy way to convert the captured images or videos between the two. You could create a completely CGI background with either but that is expensive so \"tens of thousands on anamorphic lens\" might the cheapest way to get the effect. So capturing real light in the camera just like you like it to be on screen with expensive equipment might be the cheapest option.\n\nFor other stuff, your film with large lenses and you can get shallow depth of filed and another effect directly in the camera instead of expensive or complex post-processing. There is a reason cellphone try to add this in the portate modes for images with complex software.\n\nThe different focal length of a camera has a huge effect on how stuff looks. [Look at this image](_URL_1_) that how stuff gets distorted of flattened out at 16 to 200mm lenses and the amount of background captured and how the depth of field changes and take it out of focus. The framing and distortion is nothing you can change in a computer or at least not at a cost lower to capture it directly. The depth of field is simple but not something you prefect on a movie today with automatic software.\n\nSo a lens might cost a lot of money but people that operate computers cost money too. Capturing the intention of the director directly in-camera will cost less at least regarding lenses. For a movie, tens of thousands are nothing when it cost tens millions, it is 1/1000 of the budget to make so get the right shoot directly will cost a lot less the for example \n\n & #x200B;\n\nLook at [This](_URL_0_) for a breakdown of the cost for Annie (2014) with a total cost of $73 million where the, the production cost of $34 M and shoot 23 September 2013 - 13 December 2013 (according to IMDB). That is 11 weeks and 4 days. So 81 days if all are used or 59 if you work 5-day a week. The length of the recording days are long but let's use 8 and 12 hours \n\nFor 59 day and 8 hours a day, it cots $ 72 000 per hour \nFor 81 day and 12 hours per day, it cost $34 000 per hour.\n\nSo regardless of you calculate it you get production cost of tens of thousands per hour so if the correct equipment can capture it directly or just a bit faster it will pay for itself."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://parlaystudios.com/blog/feature-film-budget-breakdown/",
"http://annawu.com/blog/wp-content/uploads/2011/08/focal-length-comparison.jpg",
"https://www.bhphotovideo.com/explora/video/features/anamorphic-lenses-key-widescreen-cinematic-imagery"
]
] |
|
2rdeen
|
why doesn't one horse equal one horsepower?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2rdeen/eli5_why_doesnt_one_horse_equal_one_horsepower/
|
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"cnev9f2"
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"score": [
7,
5
],
"text": [
"Because horses are not mass-produced at standardized specifications.\n\nIt's the same reason your foot isn't one foot long.",
"Watt (Yeah, that Watt) measured that a brewery horse could pull 32,400 foot pounds per minute, and then later simply standardized it to 33,000. That is *mechanical horsepower*, and is equivalent of 745.7 watts. What you are odds are used to is just regular horsepower, such as on Electric Motors. This is equal to 746 watts. Now, why do they differ:\n\nWhat work a horse can do changes from horse to horse, and from time to time. Consistently, a horse can do one horsepower, but peak over a short time as much as 14.9. So it is pretty much just standardization that did it. It is average work, not maximum or minimum.\n\nSource: My wonderful friend _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Horsepower"
]
] |
||
6skosl
|
outside of academia, who employs modern philosophers and what is their role in modern society?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6skosl/eli5outside_of_academia_who_employs_modern/
|
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"text": [
"I'd say lots of them write books and/or articles and essays which they sell to magazines or even get invited to tv talk shows to discuss things. A philosopher or public intellectual can also rely on making a show of his/her own on youtube and monetize on that. But I think books and generally written stuff is the main source of income.\n\nWhich ones do you have in mind?",
"I'm sure some more will come to mind soon, but the first one I thought of: Ethicists. When a company or corporation needs to go through an ethics committee, those people are philosophers. Similarly, before doing any experiments (e.g. in science) you also need to get ethics clearance. Ethics is a big domain of philosophy.\n\nEdited to add: Also, I know this is kinda covered by \"academia\", but the main thing that philosophers do is write papers for publication. Whether it's in ethics, metaphysics, aesthetics, philosophy of science, stuff about personal identity or time travel or whatever. Philosophers are the ones researching and writing about it! \n\n(Source: am married to a philosopher).",
"Two that haven't been mentioned: \nComputer science - Computers are, at the basic level, logic machines. Logic is one of the four original branches of philosophy. The best computer programmers use careful logical reasoning to solve problems in the most efficient way possible, then convert that reasoning into logic-based coding. Aristotle would've been proud. \nJudge/lawyer - Law and philosophy have a close relationship, and philosophy is one of the most common pre-law school majors. In many ways law is basically applied ethics and political/social philosphy. \n\n",
"**Copy-pasting my response to this question from a previous [ELI5] (_URL_0_)**\n\n\n > Let me start with this: my undergrad is Philosophy.\n\n > Today: Lets make a distinction between Philosophers - people who DO philosophy for a living - and philosophy students - people who use the general tenets gained by in-depth study of philosophy in their day-to-day jobs. Philosophers, those who do, tend to be employed in very limited fields, traditionally academia. These are university professors and authors. They make their money by teaching others philosophy in classes and through media (books, videos, whatever). I fall into the latter category. I use my background in philosophy in the workplace. This is what typically happens if someone does their undergrad in philosophy and gets a decent job. I \"sell\" skills like inductive and deductive reasoning, rational inquiry, the interpretation of complex material into simple terms, and excellent oral and written communication into a position I am interested in (I work in organizational development). Because I sell these things, plus experience, I can get a job that provides. That is how I, and many others, make money from philosophy. By no stretch of the imagination are we Philosophers (other than the shade-tree sort). But, if you are interested in pursuing the degree, know that it is possible to live (in the US, pretty well) if you market it well. Many use philosophy to pursue advanced degrees or positions in Law (my friend Joy), Economics ( my friend Sara), Business (my buddy Nate), or Industrial and Organizational Psychology (me and two others from my grad school cohort).\n\n > I will always remember the opening words in my freshmen \"Intro to Philosophy\" text: Philosophia non panem torrit. Philosophy bakes no bread. Philosophers, today and throughout history make very little from doing actual philosophy and very much from applying to something whether it be teaching others, solving complex problems, or maintaining an organization.\n",
"Like a lot of social sciences, Philosophers are surprisingly flexible in terms of employability. \n\nStuff like HR departments or PR employ all kinds of professionals, lecturer at a publisher, editors of newspapers, journalists all can and will occasionally employ Philosophers (or people with a degree in philosophy to be precise) \n\nIf you have a degree in philosophy you are well trained in logic, ethics and in the work with text based sources of any kind. You could even work in a SIGNIT department of a intelligence service.",
"If you're just talking about somebody with an undergraduate degree in philosophy, they are semi-common degrees for lawyers to have, as there is no pre law degree in the United States, and the subject matter taught can be useful in the profession."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://www.reddit.com/r/explainlikeimfive/comments/5q99r6/eli5_how_do_philosophers_make_money_how_did_they/"
],
[],
[]
] |
||
3i9kam
|
how does companies like steam get away with not charging sales tax?
|
The only explanation I came up with is the game is free, but you just buy the license. Is this correct?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3i9kam/eli5_how_does_companies_like_steam_get_away_with/
|
{
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"cueh4x8",
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"score": [
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"text": [
"Depending on where you live, they **do** charge sales tax. Here's what that looks like from a purchase in Illinois: _URL_0_",
"Sales tax is for the state in which the item is purchased. Until recently, online sales from out-of-state residents were exempt from sales tax, but that has since changed.",
"Sales tax and online sales are kind of messed up. First of all understand that sales tax laws change state to state. So, there is very little consistency. \n\nThe basic rules are this. If a retailer has a physical presence (like a store or office) in a state, they MUST charge sales tax on sales in that state. If there is no physical offices in a given state, the store is not obliged to collect the sales tax. \n\nSales tax must still be paid on that item however the store is not required to charge it. That means it becomes the responsibility of the purchaser to declare the purchase at tax time and pay the sales tax then. Most people never do this and it's poorly enforced.\n\nSo, while technically there is a sales tax for all online purchases, the reality is that many online purchases are never properly taxed. Over the past 10 years states have complained that this rule has caused a significant decrease in sales tax revenues. So, state by state the laws are changing. In Canada, for example, sales tax must be charged based on the shipping address (or billing address in the case of digital goods).\n\nSo the likely explanation here is that you happen to live in a state that has not changed their laws yet and where valve has no physical offices. "
]
}
|
[] |
[] |
[
[
"http://i.imgur.com/qswCv1G.png"
],
[],
[]
] |
|
1h3827
|
Would bees in flight add to the weight of an enclosed box?
|
I asked this question on [this post](_URL_0_) and was told to askscience.
If I have a box of bees that are constantly in flight, would they cause the box to weigh more than if it was empty? I know that air has weight and the bees would displace that air but I can't work out if they would make any difference in the weight of the box, assuming that the box is air tight.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1h3827/would_bees_in_flight_add_to_the_weight_of_an/
|
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"text": [
"Yes.\n\nInstead of bees, imagine a much bigger box with an Apache gunship hovering inside. The massive downward pressure generated by the blades of the chopper would add to the weight of the box, at least until all the oxygen gets burned up and the chopper crashes. ",
"Yes, but to clarify why, lets break down the bee's flight into some very critical moments in time. \n\nWe have a perfectly accurate scale that updates instantly. We have a box that weights 1 ounce and a bee that weighs 1 ounce. \n\nMoment #1: The bee is at rest inside the box. Our scale reads 2 ounces, 1 for the box and 1 for the bee. \n\nMoment #2: The bee is in flight, and is flapping her wings down. The flapping is causing her to lift up just oh so slightly from her current position. This flapping is causing a higher effective pressure under her wings. The higher pressure pushing against the wing surface applies an upward force to the bee. At the same time, the higher pressure is also pushing on the lower surface of the box, causing it to briefly register a weight greater than 2 ounces. The weight shown will be 1 ounce for the box, 1 ounce for the bee, and whatever equivalent force the high pressure under the bee's wings is applying to the bee. \n\nMoment #3: The bee has flapped her wings back up and is about to begin another downward stroke while still in mid flight. She is at this moment actually falling oh so slightly. The scale will show 1 ounce exactly. Only the weight of the box registers on the scale, and the force applied to the bee via gravity is being manifest entirely as an acceleration of the be downwards, instead of a reaction force of supporting the bee at rest. \n\nIf we were to watch the weight of the box and bee system over time, it will average at exactly 2 ounces. At any given instant while the bee is in flight, the weight of the box will vary depending on what the bee's action is having on the box."
]
}
|
[] |
[
"http://www.reddit.com/r/AskReddit/comments/1h2ksa/what_are_some_questions_that_youve_never_asked/"
] |
[
[],
[]
] |
|
2uq22b
|
why is the hydrogen car not getting more attention?
|
When I read that Toyota released the Miraj, they said it runs on hydrogen, is cheaper than petrol and emits clean exhaust fumes.
I thought this would be a huge thing and great for the world etc. But there is nothing else coming out and no media or internet fanfare.
Is this not a viable alternative to petrol cars?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2uq22b/eli5_why_is_the_hydrogen_car_not_getting_more/
|
{
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"coanuyq"
],
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2
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"text": [
"There are a couple of really big drawbacks to the hydrogen car with current technology. The first is hydrogen storage. Although hydrogen has a terrific energy density for it's weight (1 pound of hydrogen has ~3x the energy of 1 pound of gasoline) It turns out that as a gas and not a liquid, storing it is difficult and the space that the hydrogen takes up (the volume) is much much larger than the same amount of gasoline. While we can put more hydrogen in a smaller volume, that increases the pressure and is very dangerous when you want to be able to drive a car for more than a few miles without refilling. The second problem comes from difficulty of getting hydrogen. It turns out that we get a lot of our hydrogen from oil right now, producing carbon dioxide just as much as if we burned the oil as gasoline. So in the end, it doesn't make a lot of sense to use hydrogen as an alternative to gas and oil right now. That said, there are a lot of people working on ways to store hydrogen gas safely and produce it from water using solar electricity, which has only oxygen as a waste product."
]
}
|
[] |
[] |
[
[]
] |
|
gc7n9
|
How accurate is this post on the Japanese nuclear radiation issue?
|
[This post](_URL_1_) specifically, as people seem to be upvoting it slowly but surely. It originates from a [Counter-Punch](_URL_0_) post, so that might explain some things. But regardless, I'm wondering if there's any truth to what was said there.
Are there particles flying around that can get breathed in and give 3.5 million times the normal dose? Or is this entire thing a load of horse manure?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gc7n9/how_accurate_is_this_post_on_the_japanese_nuclear/
|
{
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"c1mhntc",
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2
],
"text": [
"There's truth that there are radically different impacts from different types of radiation (alpha,beta,gamma) and where they're coming from, and what tissue is being irradiated, and so on. But he's talking about [Sieverts](_URL_0_), which is a unit of \"equivalent dose\", which is meant to take into account exactly those effects. The unit for actual absorbed radiation energy is Grays.\n\nAnyway, it doesn't make much sense. Yes, the radiation at the reactors peaked (10 days ago) at 400 mSv/hour. And following that math, yes that's upwards of a few million times the background levels. \"You call that safe?\" - No, nobody calls that safe. They evacuated the workers from that area at that point. Nobody **ever** suggested it was safe to spend a whole year in those radiation levels!\n\n[This](_URL_1_) article puts the high estimate on the amount of radiation emitted at 110,000 TBq. Which would be about 1/17th of Chernobyl, about 9 times the Windscale fire and orders of magnitude more than Three Mile Island. **However**, the amount of _absorbed_ radiation by people varies _widely_ here, and so does did the consequences. TMI and Windscale differed very widely when it came to the radiation (and radioisotopes) released, but the ultimate health effects have been estimated to be about the same (~250 additional cancer cases). \n\nI think that if there's any lesson to be had here, it's that it's just way too early to tell. All guesses on how much radioactive matter has been released is exactly that, very rough guesses. And as you can tell from the above, the health consequences don't really scale with it either. It depends on which isotopes, how they were released and where and so on. \n\nAt the moment I don't see reason for a lot of worry. The detected levels around the area are still fairly low and as of latest, slowly declining. It's worth remembering that we can detect radioisotopes very accurately at very low concentrations. And when you're talking about legally-allowed limits, those are very low and conservative numbers. Since obviously it's not acceptable to have anybody die or get sick from having allowed contaminated food or water. \n\nMost of the radiation reports right now are about high I-131 levels in water. It's a short-lived, beta-decaying isotope, making it harmful if ingested, but not very harmful otherwise. So if you don't drink the water, you'll be okay. Due to it's short half-life, 99% of it will be gone in two months. Cesium is a much bigger concern, since it's long-lived. \n\n",
"There are elements of truth to everything he's saying but it's all distorted and exaggerated.\n\nFor instance, he says that they are not capping the reactor because they want to avoid the loss of all the other units. But the Chernobyl plant remained open after the explosion for 15 more years, so why couldn't the Fukushima plant remain open? Perhaps there is a reason, but I think he is just speculating."
]
}
|
[] |
[
"http://www.counterpunch.org/takashi03222011.html",
"http://www.reddit.com/r/todayilearned/comments/gbypx/til_chernobyl_is_closer_to_new_york_than/c1mghn1"
] |
[
[
"http://en.wikipedia.org/wiki/Sievert",
"http://www.asahi.com/english/TKY201103250204.html"
],
[]
] |
|
bge2yw
|
how exactly do trees get sick and how do plant related sicknesses spread?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bge2yw/eli5_how_exactly_do_trees_get_sick_and_how_do/
|
{
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],
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"text": [
"There is various ways, via pathogens or insects such as earwigs,apheids, mealy bugs that eat the leaves and the bark, spreading from tree to tree. Dead rotten tissue spreads. \n They can spread if not contained. They are contained using a range of methods such pesticides. Chemicals that kills pests. Or pruning where the dead or infected tissue is cut way. Diseases can also be contained via biological methods that involve the use of lady-bugs to kills the pests."
]
}
|
[] |
[] |
[
[]
] |
|
1r9y49
|
why is over penetration from a bullet a bad thing?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1r9y49/eli5_why_is_over_penetration_from_a_bullet_a_bad/
|
{
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2,
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"text": [
"If a bullet goes into the target and comes out the other side, it is dangerous to anyone nearby. It might go straight through or ricochet in unpredictable ways. When dealing with firearms, you want the result when you pull the trigger to be as predictable as possible.",
"If a bullet goes through its target, the remaining kinetic energy that it has is wasted and it also has the potential to damage other things in its trajectory. Ideally bullet hits its intended target and deposits all of its kinetic energy into it in a fashion that causes maximum damage.",
"It's interesting to note that hollowpoints, which help prevent over penetration, are illegal in warfare. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
18dsau
|
why is rope so strong?
|
Why not just have straight strands?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/18dsau/why_is_rope_so_strong/
|
{
"a_id": [
"c8dvxh2"
],
"score": [
5
],
"text": [
"Imagine you have to try and lift a giant cube of iron by some handles on top. Likely, it'll be too heavy for one arm. However, use your other arm as well, and get a friend to help - it will be much easier, because you're splitting the weight among every arm, and each will have a small load, instead of one with a large load.\n\nBraided ropes work in much the same way - if you try to put too large of a load on one strand, the strand will snap. However, if you add another strand, or a dozen, or a hundred, or a thousand, it will be much stronger, and will be able to hold more, because the load will be split among every single strand.\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
cjtt12
|
Writing first dissertation: guidance on research and writing
|
Hi there,
Calling out to all of you wonderful, fascinating, historical beasts out there for assistance in writing my first historical dissertation., I am doing this outside of uni, and do not have access to that kind of material (pre application work)
Some quick questions:
How do you yourselves find historical sources? Validate them?
What is the nature of historical research? (and what do you enjoy about it :D )
How do you feel you organise your writing and research best? Any guidance? Im a little intimidated but want to prove my passion
Any insight on: *Orthodox interpretations of history, Revisionist interpretations of history , Marxist interpretations of history, Feminist interpretations of history* which i need to include in my Assesment Objectives
& #x200B;
Thank you
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/cjtt12/writing_first_dissertation_guidance_on_research/
|
{
"a_id": [
"evgh3yz"
],
"score": [
2
],
"text": [
"Read as much as you can. Don't come up with a question/focus until you've exhausted your reading. I used the bibliography of good overview books to get deeper reading. Local university libraries often let you in for free but don't let you borrow books.\n\nI referenced books/journals/articles as I researched to save time at the end. I typed up all the parts I wanted to use so I basically had a database for my topic.\n\nGet some solid sources to use. History can only happen from strong sources. Read them till you know your topic inside out.\n\nDon't be afraid of going down a rabbit hole. In that I mean it can be worrying going of piste as you look at references and look at the references from this references but they can sometimes broaden your knowledge or lead you to some other area that can aid your research.\n\nOther than that, enjoy!"
]
}
|
[] |
[] |
[
[]
] |
|
z4qzb
|
Would it ever be possible for the sky to be anything but blue?
|
I know the blue tone comes from blue light being scattered more easily than red light by the air. Would there ever be conditions that could turn our sky more toward the red end of the spectrum?
|
askscience
|
http://www.reddit.com/r/askscience/comments/z4qzb/would_it_ever_be_possible_for_the_sky_to_be/
|
{
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3
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"text": [
"The colour of the sky can change if there's particulate matter blowing around.\n[Red Sky in Sydney](_URL_0_) but I suspect that's not what you wanted?",
"Yes. If the Sun was a red giant, our sky would be more red than it is now. This will actually happen in about 4 billion years. Even though Earth has a longer life expectancy (tectonic activity) than the Sun, the Sun will engulf the Earth and vaporize it as it expands and consumes the rocky planets (Mercury, Venus, Earth, Mars)"
]
}
|
[] |
[] |
[
[
"http://www.smh.com.au/environment/weather/sydney-turns-red-dust-storm-blankets-city-20090923-g0so.html"
],
[]
] |
|
24hsex
|
Is there a physiological (or maybe psychological) explanation for "Crazy Eyes"?
|
askscience
|
http://www.reddit.com/r/askscience/comments/24hsex/is_there_a_physiological_or_maybe_psychological/
|
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"text": [
"Damage to the amygdala produces deficits in the ability to recognize fear due to attentional neglect of other people's eyes. Interestingly, children with high psychopathic traits also show problems recognizing fear; however, the reasons for this are not known. This study tested whether psychopathic traits are associated with reduced attention to the eye region of other people's faces. Attention to other people's eyes is reduced in young people with high psychopathic traits, thus accounting for their problems with fear recognition, and is consistent with amygdala dysfunction failing to promote attention to emotional salience in the environment. Impairments in eye contact are characteristic of children\nwith callous–unemotional traits.\n\nSource: [Dadds, M. (2008). Reduced eye gaze explains \"fear blindness\" in childhood psychopathic traits. J Am Acad Child Adolesc Psychiatry, 47(4), 455-463. doi:10.1097/CHI.0b013e31816407f1](_URL_0_)",
"The \"crazy eyes\" expression is both intense and fixed. It's well known that certain areas of the brain are responsible for recognizing and processing static images of faces. There appears to be some evidence that facial expressions are also processed separately in more motion sensitive areas (_URL_0_). Intense facial expressions are typically fleeting rather than fixed. Incongruities between the recognition of the faces' static expression and motion characteristics could potentially explain the crazy eyes phenomenon.",
"There has been some interesting research about increased activation of the amygdala in response to a large amount of sclera being visible. Fearful eyes tend to show much more white, and the idea is that the amygdala has evolved to interpret this accordingly and alert us to potential danger.\n\nMost of the pictures you posted have that \"wide-eyed\" look with more sclera showing than what one might consider normal, which is a possible reason why when we look at their eyes we tend to get the feeling that something's not quite right. It doesn't explain why they have wide eyes necessarily, but it does help explain why we might be able to pick them out as being abnormal.\n\nThere's a picture here that shows a comparison of fearful and normal sclera: _URL_0_",
"Would you mind posting an example. Are you asking why \"crazy eyes\" looks unusual to someone else?"
]
}
|
[] |
[] |
[
[
"http://brain.oxfordjournals.org/content/136/8/2550.full"
],
[
"http://www.jneurosci.org/content/32/45/15952.full"
],
[
"http://emotion.caltech.edu/dropbox/bi133/files/Whalen%20et%20al.pdf"
],
[]
] |
||
b3vem6
|
How do germs/bacteria travel exactly?
|
If I drop food on the floor, there's no way I'm eating that food. However, if I place a plate of food on the floor, I'd still eat the food off that plate. Do germs and/or bacteria manifest only on whatever it comes in direct contact with, or will it spread around (in my example, around the plate and onto the food)?
|
askscience
|
https://www.reddit.com/r/askscience/comments/b3vem6/how_do_germsbacteria_travel_exactly/
|
{
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"text": [
"It all depends, most pathogenic bacteria live in a water environment so they'd have to some kind of direct contact to that to spread. This is why the CDC always preaches to clean up raw chicken juice while cooking and to properly wash your hands after using the toilet.\n\nOther bacteria can float in the air, like botulism. It forms spores that are considered to be ubiquitous in the environment. This is why any low acid canned food has to undergo a very specific decontamination process or else it all gets recalled.\n\nA combination of these two, wet environment + airborne can happen when we cough or sneeze or even breathe, tuberculosis loves getting around this way but when you flush the toilet you with the lid up, you can aerosolize fecal bacteria like E. coli and have them settle on say your toothbrush or open contact lens case.\n\nIn your plate example, bacteria are attracted to things they can \"smell\" in the water so it would be extremely unlikely for them to travel from the floor, on and around the plate, and to the food.\n\nIf anyone is interested in infectious disease news, feel free to check out: r/ID_News",
"PHealthy gives a good practical explanation of how bacteria spread, but we can get down and dirty. The topic is called Bacterial Locomotion and Signal Transduction ([BLaST](_URL_3_)) if you want to look up more research.\n\n & #x200B;\n\n1. The most iconic method is probably **flagellae**, which are corkscrew like appendages made of protein on the cell surface. Bacteria can have just one, a pair, or quite a few. These work through a [proton motor](_URL_0_) which creates a gradient of H^(+) ions separated by a membrane (this is also how you make ATP!). The motor rotates the filament CW or CCW which allows it to move forward, backward, or tumble.\n2. Similarly, bacteria like spirochaetes can form [endoflagella](_URL_4_) which essentially turns their entire body into a flagella, corkscrewing their way around. They work by structural proteins inside the membranes that contract and expand.\n3. Lastly, bacteria can move by gliding. Typically this is achieved by pili (smaller protuding filaments used for different functions). These proteins act as little feet that [hook on to surfaces and pull them around.](_URL_5_) Some bacteria have been observed to secrete slime and use the contracting surface tension to move, but most gliding mechanisms are still not fully understood.\n4. If we expand our discussion to eukaryotes, they also use flagella, but they also include cilia and pseudopodia. [Cilia](_URL_1_) are basically mini-flagella hairs that move the liquid around them. Pseudopodia (literally *fake-feet*) are extensions of the cell body that expand in the direction of travel and contract for movement. They're also used for detection.\n\n & #x200B;\n\nYou might have noticed that most of these, except for maybe pili, require the bacteria to be in a liquid environment. It is very hard for most microbes to survive outside of an aqueous environment. The only thing separating their precious cytoplasm from the outside is a permeable membrane which means eventually if they don't find water, diffusion will result in all the water leaving their cells. Since the average bacteria is only [3-5 micrometers](_URL_2_), moving a million times their body size would only get them 3 - 5 meters. To put that in human scale, that would be a trip from SF to NY and back. For a bacteria to move from under your plate and around to the top in any reasonable sense of time is preposterous. As PHealthy stated, it is much more feasible for bacteria to catch a ride on air currents because they are so small and light. "
]
}
|
[] |
[] |
[
[],
[
"https://jb.asm.org/content/jb/180/5/1009/F1.medium.gif",
"http://www.vivo.colostate.edu/hbooks/pathphys/digestion/herbivores/bugs1.jpg",
"https://hypertextbook.com/facts/2001/JoyceWong.shtml",
"https://jb.asm.org/content/180/5/1009",
"http://cronodon.com/BioTech/Bacteria_motility3.html",
"https://1.bp.blogspot.com/_Wo_zmmodH_g/TL7tzNbUvYI/AAAAAAAAAZg/f72ufclKXb0/s400/gliding.JPG"
]
] |
|
2wsqc4
|
Why do plants seem to be more likely than animals to survive with mutations that duplicate entire sets of chromosomes?
|
I was under the impression that while polyploidy-causing mutations are common for plants, such mutations usually cause animal embryos to miscarry before they can be carried to term. Is this true? If it is, then why?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2wsqc4/why_do_plants_seem_to_be_more_likely_than_animals/
|
{
"a_id": [
"coudj4u"
],
"score": [
4
],
"text": [
"It is true that plants can generally tolerate polyploidy much more easily than animals. It is possible that animals are more prone to polyploidy than we had first expected, since the cytogenetics of large wild populations isn't something usually done with animals, whereas with plants taking large numbers of samples is easier and more common practice, but this hasn't been confirmed.\n\nPolyploidy has been correlated to [geographic distribution](_URL_1_), with higher latitudes and more temperate climates producing more instances of nondisjunction in gametes which can lead to polyploidy. \n\nWay back in 1925 H.J. Muller first pointed out that polyploidy was more common in plants than in animals. The mechanism he proposed had several problems, and a [review](_URL_0_) of his paper in 2004 by Mable has more of a synthesis of views from biologists as to why. The newer hypothesis is that polyploidy is important in terms of a mechanism for evolution. The reproductive strategies of most animals (especially placental mammals) take precedence over any fitness conferred from polyploidy and if polyploidy is present it tends to short-circuit these strategies leading to death. However some animals do fairly well with polyploidy, like certain kinds of fish.\n\nPolyploidy is also much more likely in organisms that practice assortative mixing, which put simply is a selection bias in favour of organisms with similar characteristics. For example many tetraploid plants have larger reproductive structures like flowers, increasing the chance of pollination and reproduction with other tetraploids."
]
}
|
[] |
[] |
[
[
"http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.2004.00332.x/full",
"http://www.ufv.br/dbv/pgfvg/BVE684/htms/pdfs_revisao/mutagenese_transposon/Polyploidy.pdf"
]
] |
|
1on4h4
|
How significant was the input of Subutai/Tsubodai to the success of both Genghis Khan's individual battles and long term campaigns?
|
As far as i know, Tsubodai was the main military strategist for Genghis Kahn. Did any of his strategies win battles that would have been lost without him? Was he actually that important to the overall conquering of other nations and would the Mongolian empire have been as powerful without him?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1on4h4/how_significant_was_the_input_of_subutaitsubodai/
|
{
"a_id": [
"ccu1ylq",
"ccu3yvh"
],
"score": [
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"text": [
"Genghis was a genius in the choosing of his Generals. It did not matter what their background may have been since Genghis practiced a system of Meritocracy anyone who proved their worth would be promoted. Subutai was one of these men, he was not a Mongol, only a blacksmith's son who was a servant to Temujin. After Genghis' rise in power Subutai was promoted to be one of Genghis' four top generals. Who would make his first significant contribution to the expansion of Mongol power in Northern China.\n\nTo conquer the Great Wall Genghis sent Subutai to invade from the North to attract the attention of the Chinese army there while the bulk of Genghis' army could march in from the west which gave Genghis the time to get across the wall before meeting the Jin in battle. Subutai would lead in vanguard at the start of the Khwarizm invasion. He was also able to subdue Russia even with the Russians Knights having superior weapons. All of these battles were integral to the overall expansion of the Mongol Empire and in true Mongol fashion these battles were not won but superior numbers or equipment but by trickery and outstanding battlefield tactics. Subutai was not only important for expanding the empire but also for the rise of Genghis. After Temujin's defeat at the hands of his rival, Jamuka, Subutai remained loyal and fought for Genghis until Jamuka was killed by Temujin sympathizers. All of these major battles were won with inferior numbers, without knowing about the brilliance of the Mongol generals it would seem that almost every battle Subutai was involved in was sure to be a decisive defeat and a quick ending to Genghis and the Mongols.\n\nOops, forgot to mention you can pull most of my info from _URL_0_",
"A great question. And I can see that there are now two Mongo experts in the field of battle!\n\nSubutai/Tusobodai as he was actually called, overran more territory than any known commander in the history of warfare.^1\n\nHe did this through his sheer brilliance in logistical and imaginative strategy. If Genghis Khan was the soul of the Mongolian Empire through its rise. One can argue that it was Subotai who later wielded the sword that allowed the Mongolians to conquer nearly half of Europe, nearly all of Asia and the only nation thus far to have defeated the descendants of the Russian people (The Empire of Rus) \n\nSubutai also used unconventional tactics that at our age would seem very normal and common sense, but Subutai would later be recorded as arguably the very first commander to use Siege weapons in an offensive manner in a non-siege battle. You could almost say that he was the first to use artillery in the ancient world.^2\n\nIf you have any more questions I can definitely answer them too!! \n\nIt's a great question. \n\n1. [Subutai and his records](_URL_0_)\n\n2. [Siege Warfare and Subutai's first recorded usage](_URL_1_)\n\n3. [Also](_URL_2_)\n\n"
]
}
|
[] |
[] |
[
[
"humanities360.com"
],
[
"http://www.amazon.com/Great-Captains-Unveiled-Liddell-Hart/dp/030680686X",
"http://www.amazon.com/Strategy-Second-Revised-Edition-Meridian/dp/0452010713/ref=pd_sim_b_1/176-3940519-8665963",
"http://books.google.ca/books?id=tFQcwH2StsMC&pg=PA89&dq=At+Mohi+on+April+111,+Mongols+versus+Christians+During+the+invasion+of+central+Europe,+directed+by+S%C3%BCbedei+in+1241,+Mongol+horsemen+proved+superior+to+armoured+Christian+knights+in+both+subtlety+of+manoeuvre+and+speed+of+movement.+he+drove+the+army+of+the+Hungarian+king,+Bela+IV,+into+confused+flight+with+a+frontal+attack+across+a+river+%E2%80%94+supported+by+rock-throwing+catapults+used+as+field+artillery%E2%80%94and+a+simultaneous+flank+attack+delivered+from+a+concealed+position.+S%C3%BCbedei%27s+horsemen+pursued+and+massacred+the+Christian+troops+as+they+fled.&hl=en&ei=FrPVToH1FMfq0gGIy6iMAg&sa=X&oi=book_result&ct=result&redir_esc=y#v=onepage&q=At%20Mohi%20on%20April%20111%2C%20Mongols%20versus%20Christians%20During%20the%20invasion%20of%20central%20Europe%2C%20directed%20by%20S%C3%BCbedei%20in%201241%2C%20Mongol%20horsemen%20proved%20superior%20to%20armoured%20Christian%20knights%20in%20both%20subtlety%20of%20manoeuvre%20and%20speed%20of%20movement.%20he%20drove%20the%20army%20of%20the%20Hungarian%20king%2C%20Bela%20IV%2C%20into%20confused%20flight%20with%20a%20frontal%20attack%20across%20a%20river%20%E2%80%94%20supported%20by%20rock-throwing%20catapults%20used%20as%20field%20artillery%E2%80%94and%20a%20simultaneous%20flank%20attack%20delivered%20from%20a%20concealed%20position.%20S%C3%BCbedei's%20horsemen%20pursued%20and%20massacred%20the%20Christian%20troops%20as%20they%20fled.&f=false"
]
] |
|
1uasc2
|
During World War II, how were American infantry weapons regarded by the other world powers?
|
Were American weapons typically held in high esteem? I am particularly interested in hearing the German opinion.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1uasc2/during_world_war_ii_how_were_american_infantry/
|
{
"a_id": [
"cegftbq"
],
"score": [
38
],
"text": [
"If we're speaking about pure technical analysis it's hard to find primary sources and there is a lot of post-war speculation about various nations opinions on other nations equipment that I would not be too hasty to trust. The best lead would be to peruse [this](_URL_1_) copy of the German published \"Guide to Foreign Weapons\" (Kennblätter fremden Gerats) which was issued to troops and commanders during the war. \n\nI'm going to leave the technical side there because it seems difficult to find reliable information but there is another point I would like to make:\n\nThroughout the war the small unit infantry tactics of different nations were generally different enough that the strengths of possibly technically superior weapon would be negated. I'll leave the objective comparison of German and American weapons to the frothing historical-gun-nuts who are wholly more qualified than I am to make such comparison. Rather I would posit that, for example, the German opinion on the semi-automatic M1 Garand rifle would have been that it was wholly unnecessary and expensive a tool for a rifleman to fulfill his role of assaulting positions and providing lethal fire at range. This is because German infantry tactics at the time called for suppression and elimination of the enemy to be performed by a squad central machine-gun while riflemen and grenadiers were there only to assault positions and take available shots from a position of immense fire superiority. For this role, a simple bolt-action rifle is more than sufficient and much much cheaper.\n\nContrast this with the American tactic of providing decentralized fire superiority from a squad of almost entirely riflemen and it become obvious why they placed such value in a mass-issued long range semi-automatic firearm. Rather than operating in a firefight with fire superiority assured, American riflemen had to fight to establish that fire superiority with his own weapon. \n\n[This article](_URL_0_) does a good job of explaining the differences and it corroborates with what I have read elsewhere. These differences in tactics generally dictated the development of small arms and so each nations arsenal generally corresponded best with how they fight. As a result, I find it hard to believe that any nations during the war would have so coveted the weapons of any other nation at any sort of tactical level based on their usefulness. \n\nThat being said, soldiers have and always will be soldiers, and if there is one thing soldiers love to do it's complain about their equipment. So no doubt pilfering of enemy or even friendly equipment happened on a smaller scale on all sides of the war."
]
}
|
[] |
[] |
[
[
"http://www.dererstezug.com/TacticalPhilosophies.htm",
"http://books.google.com.au/books/about/Kennbl%C3%A4tter_fremden_Ger%C3%A4ts.html?id=35We_Y2pgg0C&redir_esc=y"
]
] |
|
3a40x5
|
Was the American eugenics movement responsible for the holocaust?
|
I recently started reading Edwin Black's book "The War Against the Weak: Eugenics and America's campaign to create a Master Race" and what he seems to be asserting is that the American eugenics movement of the progressive era is what inspired the Nazis' ideals that eventually lead to the holocaust.
How true is this? I have always been aware of the eugenics movement and it was touched on briefly during my schooling, but I have never seen anyone else draw a correlation between American eugenics and the creation of Nazi ideals. It wouldn't surprise me, but I'd like to know more about this subject from other sources than just his book.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3a40x5/was_the_american_eugenics_movement_responsible/
|
{
"a_id": [
"cs9jggw",
"cs9uuv8"
],
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17,
2
],
"text": [
"This is a tricky sort of historical question. If the question is, can we trace a genealogy of ideas from the American eugenics movement to Nazi Germany, and from there to the Holocaust? — the answer is yes, we can. It is actually very easy since the Nazis were happy to point to American influences. Madison Grant's _The Passing of the Great Race_ (1916) reads like a primer in how to justify an ethnic cleansing. (Hitler apparently called it \"his Bible.\") The advocacy and studies of compulsory sterilization movements by people like Harry Laughlin was directly cited by the Nazis in defense of their own (much larger) sterilization program. The connection between Nazi eugenic ideology and the Holocaust is not quite as direct as it is sometimes made out to be, but there is a real connection (it is just a little more roundabout than the simplified version). So in a sense you can see the American influence.\n\nOn the other hand, if you are implicitly asking a counterfactual (which is what a \"strong\" version of this claim would be doing), i.e., if the American eugenics movement hadn't existed, would the Holocaust still have happened? — that is very hard to answer, but I am inclined to say, while the US movement certainly was leveraged as ideological support by the Nazis, the Nazi racial hygiene movement was in many ways independent of the American strain of eugenics, only borrowing from it at very specific times (e.g. to justify sterilization on the basis of US studies that sterilization caused little harm). It is not entirely clear how much of the Nazi ideology was really American in origin, or whether citing ideological heritage to the United States was a propaganda move to say, \"even they are doing it.\" I am just not so sure I would lay that much responsibility at the hands of a few books; the forces that led to the Holocaust were deeper than Madison Grant, deeper than Harry Laughlin. \n\nSo I would be more cautious than Black at drawing this direct line of causation. There were interconnections between the programs. There were mutual admirations and citations. But do we really think that Nazism would haven't existed without the US writings? I find this a dubious historical claim. \n\nBlack's work is not bad from a research standpoint but he often goes for the most sensationalistic interpretations possible, drawing thick, direct causal arrows where most historians would see murky interactions at best. (His _IBM and the Holocaust_ also suffers from this approach. Were Holerith machines necessary/useful for the Final Solution? Yes. Does that mean IBM has complicity in the Holocaust? Not really.)",
"The other side of the Holocaust was of course rampant anti-semitism and hatred for certain ethnical groups. That has been present in Europe for centuries, against specifically Jews and gypsies (Roma, Sinti and the third group whose name I always forget). \n\nSo while much of the eugenics stuff neatly tied in with what the Nazis wanted, as restricteddata explained, it's impossible to pin the other half, the hatred-half, on eugenics, much less American eugenics. Jews were persecuted in Europe way before the Thirteen Colonies were even a thing, the sentiment was not new. \n\nLike so many things mired in hate, the Holocaust is a terrible coming-together of many ideas and awful 'traditions'. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
43yndx
|
WWI Austria-Hungary uniform question
|
I'm trying to get some info on the soldiers in [this picture] (_URL_0_). I'm pretty sure that they're Austro-Hungarian based on the uniforms, particularly the cloth field caps that some of them are wearing. I'm not 100% sure, but I've never seen that type issued elsewhere.
I don't know whether Austrian and Hungarian uniforms were distinct from one another, and I don't know what information, if any the facings on the soldiers' collars convey, or what kind of unit these guys were likely assigned to. Any information would be appreciated.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/43yndx/wwi_austriahungary_uniform_question/
|
{
"a_id": [
"cznf4sn"
],
"score": [
2
],
"text": [
"Short before WWI it was already clear to A-H, that the formerly used multi coloured uniforms are obsolote. Here is an [illustrated article](_URL_1_) (in Hungarian) with the new uniforms, that were used form 1908. The soldiers on your photo do look like soldiers of the A-H army.\n\nThe next problem the Monarchy faced was the fast development of weapons in WWI. In the first years of war it was hard to tell the difference between granadiers, machinegunners or artillery infantrymen. Thats why they started to use (temporary) sewed linen squad insignias on the neckpieces, and later the [metal insignias](_URL_0_), to identify the branches.\n\nSorry but the photo is too blurry to see the insignias and identify the branches, but im almost sure the picture was taken between 1908 and 1917."
]
}
|
[] |
[
"https://i.imgur.com/VYT58QX.jpg"
] |
[
[
"http://militiahungarorum.roncskutatas.hu/1867_k_a_c_f.html",
"http://nagyhaboru.blog.hu/2014/08/14/az_osztrak-magyar_hadsereg_egyenruhai_1914-ben"
]
] |
|
mosk1
|
why do so many politicians abuse their power ?
|
Hardly a week goes by without a report on some elected official abusing the system or taking kickbacks etc. What causes so many supposedly good people to turn bad ?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/mosk1/why_do_so_many_politicians_abuse_their_power/
|
{
"a_id": [
"c32mcd7",
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"c32oba7",
"c32mcd7",
"c32mt9e",
"c32nmj0",
"c32oba7"
],
"score": [
26,
3,
3,
2,
26,
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2
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"text": [
"You are assuming they are good in the first place. To reach that level of political success you have to have some moral flexibility.\n\nThe more you delve into ends justifying means you become more of a sociopath/narcissist to the point where you do no think the consequences apply to you anymore.\n\nAt least that is what happened to me after I won my 3rd Grade class presidency.",
"people spend a fair amount of their lives yearning for power mainly just for the sole purpose of giving themselves an advantage over other people. once politicians get that power, many of them decide that it's time for them to get what they \"deserve\"",
"There are thousands and thousands of politicians in the country (many, many more if you are including international scandals like Berlusconi). While, undoubtedly, there are politicians that take kickbacks/are otherwise involved in shady doings who are never uncovered, the Blagojevichs are far outnumbered by politicians who are never implicated in any wrong doing. \"Politician plays by the rules!\" just isn't a very exciting news story. ",
"The way I tend to see it is that their intentions are often good. Let's say that a politician has a dream of some kind, then someone offers them a large amount of money if they do some favour for them. The politician understands that they need the money to accomplish their goals, so they make small concessions in order to get there.",
"You are assuming they are good in the first place. To reach that level of political success you have to have some moral flexibility.\n\nThe more you delve into ends justifying means you become more of a sociopath/narcissist to the point where you do no think the consequences apply to you anymore.\n\nAt least that is what happened to me after I won my 3rd Grade class presidency.",
"people spend a fair amount of their lives yearning for power mainly just for the sole purpose of giving themselves an advantage over other people. once politicians get that power, many of them decide that it's time for them to get what they \"deserve\"",
"There are thousands and thousands of politicians in the country (many, many more if you are including international scandals like Berlusconi). While, undoubtedly, there are politicians that take kickbacks/are otherwise involved in shady doings who are never uncovered, the Blagojevichs are far outnumbered by politicians who are never implicated in any wrong doing. \"Politician plays by the rules!\" just isn't a very exciting news story. ",
"The way I tend to see it is that their intentions are often good. Let's say that a politician has a dream of some kind, then someone offers them a large amount of money if they do some favour for them. The politician understands that they need the money to accomplish their goals, so they make small concessions in order to get there."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
1t43a2
|
what is the consumer price index, cost-of-living adjustment, and why is there debate about which is better to use?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1t43a2/eli5_what_is_the_consumer_price_index/
|
{
"a_id": [
"ce444a4",
"ce44y4l"
],
"score": [
2,
2
],
"text": [
"I think you might've gotten confused somewhere along the line. The COLA (cost-of-living adjustment) is directly based on the CPI (consumer price index).",
"The Consumer Price Index is a calculation performed by the Federal Government's Bureau of Labor & Statistics to determine the cost of a \"basket\" of goods and services. There are several different indexes that economists use to get a sense of how inflation is affecting the economy. The most commonly used CPI, and the CPI that most people are directly affected by is CPI-U, which looks at the basket through the lens of people who are in urban locations. (Stuff in cities costs more than stuff in the countryside due to taxes and overhead). CPI-U applies to about 87% of the US population.\n\nThe basket of goods and services is supposed to represent a broad cross section of the stuff people spend money on - food, clothing, rent, fuel, etc.\n\nThe prices of those things are checked by anonymous investigators who go into stores and get the price of specific items on a regular basis. So they don't look for the best deal on blue jeans, they look for the price of a specific Levi 501 jean in a certain size. All the investigators use the exact same product specifications so the prices they are gathering are on the same products. The prices are collected in 87 \"urban areas\". (An \"urban area\" might be a stand alone city like Seattle, or it might be both Brooklyn and Manhattan in New York).\n\nHere's a link to the FAQ from the BLS:\n\n_URL_0_\n\nThe theory behind the CPI is that if you track the prices of these goods over time you can see how their prices increase (inflate) or decrease (deflate) and use that as a proxy for large sectors of the economy. By gathering the data in a wide variety of places and averaging the results you can remove some of the bias that might occur from local economic effects or distortions. Generalizing the CPI to the whole economy is a way of deciding if prices are staying the same, going up or going down.\n\nA Cost of Living Adjustment is a way of changing someone's compensation so that as prices inflate their wages retain the same buying power. Imagine that you were paid $10/hour, and the price of a movie ticket was $10. One hour of your labor would be worth one movie ticket. If the price of the ticket went to $12, but your salary remained at $10/hour, you'd have to work longer to buy that ticket. If you got a \"Cost of Living Adjustment\" that increased your pay to $12/hour, you would not really have gained anything, since it would still take an hour of your labor to buy one movie ticket. \n\nSince most economies generate inflation (Japan is really the only recent exception in terms of advanced economies) without some kind of Cost of Living Adjustment, you are essentially taking a pay cut every year. Inflation in the United States averages between 1% and 3%, so after 10 years, that pay cut could be effectively 10% to 30%.\n\nUnderstanding how CPI is changing should help you negotiate for pay increases with your employer."
]
}
|
[] |
[] |
[
[],
[
"http://www.bls.gov/cpi/cpifaq.htm"
]
] |
||
37m142
|
What are good books about Propaganda Posters?
|
Dear people of /r/AskHistorians. I bought a book today about Chinese Propaganda Posters (Wolf, M (2011)*Chinese Propaganda Posters.* Cologne: Taschen). It is really amazing how all those cold-war Chinese Propaganda posters are bundled in one book. Now is my question: Are there books like this for other nations as well, such as the U.S.A, Nazi-Germany or Sovjet Russia? I would really like to invest more into these books as I can use them for my job (History teacher). The era of the posters/propaganda does not really matter. I have no clue if this is the right subreddit to ask this question. If not, please delete it. However, thank you in advance!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/37m142/what_are_good_books_about_propaganda_posters/
|
{
"a_id": [
"crnu44f",
"crnydtz"
],
"score": [
2,
2
],
"text": [
"Can't recommend a book but I can recommend you ask over at /r/propagandaposters ",
"David King has produced a number of handsome hardcovers on Soviet imagery: *Red Star Over Russia* and *Russian Revolutionary Posters* sound like what you're looking for. To be clear though: these are more coffee-table books (ie largely comprised of pictures) than academic works on the detail of Soviet propaganda."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2q87jw
|
what's so hard about human cryo-tech? preserving a healthy human and then defrosting 100 years later alive?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2q87jw/eli5_whats_so_hard_about_human_cryotech/
|
{
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31,
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4,
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],
"text": [
"When water freezes, it forms tiny ice crystals. When those crystals form inside cells, they rip apart the cell membrane causing irreparable damage. ",
"When complex multi-cellular structures are frozen, they die. No technology has been able to stop this to date. In other words if you freeze a healthy and alive person, the freezing process will kill them. When you defrost them, you will be defrosting a corpse. ",
"In the United States, cryopreservation of adult humans can only be done on someone who has been declared legally dead, otherwise it counts and murder and/or assisted suicide (after all, no one has been revived after cryopreservation ... you may note that this is a bit of a catch-22). Thus nobody is legally allowed to try preserving and eventually reviving a healthy person in the U.S.. \n\nAs for the practical difficulties, there are several, but there are also ways of dealing with them. [Cryopreservation](_URL_0_) of cells, tissues, and even human embryos is very much in use. That page discusses both the risks (mostly related to ice crystal formation) and ways of dealing with them, and mentions that more than three hundred thousand live births have resulted from cryopreserved embryos. Multiple studies have shown no negative effects on the resulting children. \n\nThe larger the chunk of tissue involved, the more difficult the current methods for avoiding negative side-effects become. Adult humans, or even large organs such as hearts or livers, are quite large and thus more difficult to preserve than individual cells or embryos. One possible method is \"vitrification\" through the addition of cryoprotectant chemicals to the person's body fluids. The chemicals discourage ice crystal formation and promote instead the formation of an amorphous, glassy solid as the mixture of water and cryoprotectant cools. This thus prevents damage from ice crystal formation. However, the chemicals themselves are toxic in high concentrations, and such concentrations are generally required for proper vitrification in large tissue samples. I believe whole large human organs have not been successfully cryopreserved ... yet. Research continues. Mentioned in the Wikipedia page was that one company has successfully preserved a rabbit kidney (using their own proprietary mix of cryoprotectants), thawed it out, and shown that it functioned properly when transplanted into a rabbit, so smaller human organs might be possible as well. ",
"Well first of all, as most of the comments below indicate when you freeze water or even lipid-based structures like those in our cells, you cause irreparable damage to the structure, the molecular information, and it's very undesirable.\n\nThe best way therefore is to actually slow down biochemical and metabolic processes but we don't even understand the full range of them let alone how one stimuli affects an entire process in full or totality. \n\nCyro-tech is difficult because it's not meant to be an end-all tech, it's the worst best step in the direction of indefinite suspension and the hope is that by freezing people, you do minimal damage to non-essential tissues but leave enough DNA intact that far into the future it can be used to repair or recreate the damaged tissues or, if need be, create a copy of said person."
]
}
|
[] |
[] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Cryopreservation"
],
[]
] |
||
83m7ue
|
why does coughing tear up your throat when all you are doing is expelling air?
|
Sick and random thought occurred, thought I'd ask.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/83m7ue/eli5_why_does_coughing_tear_up_your_throat_when/
|
{
"a_id": [
"dvivqh9"
],
"score": [
10
],
"text": [
"A cough is a vigorous expulsion of air to eject a foreign object or whatever is irritating you airways. To get that you are closing off your throat at the epiglottis, then building up some pressure behind it before opening the airway so the air comes out in a rush. That fast flow causes the soft tissues to vibrate together as the air passes over them.\n\nThink of the way that the neck of a balloon vibrates and makes that distinctive sound when you let the air out.\n\nIn addition, your throat tissues are probably already sore and inflamed from the irritation by whatever is making you cough."
]
}
|
[] |
[] |
[
[]
] |
|
2ao0y1
|
Looking for a book covering the end of the Third Reich
|
I am looking for a book that covers the end of the Third Reich. I am interested in the lead up to and conclusion of the Battle of Berlin, the subsequent German capitulation, Victory in Europe, Nuremburg Trials, and the fates of the various Nazi officials, heads of government, generals, etc.
Stories about the collapse of great powers really interest me and I enjoy spending many hours reading about such things on Wikipedia, though I am looking for a more in-depth book about Germany specifically. Also I would prefer it to have an eBook version
THANKS, FRIENDS.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2ao0y1/looking_for_a_book_covering_the_end_of_the_third/
|
{
"a_id": [
"cix1w4g",
"cix22or"
],
"score": [
3,
3
],
"text": [
"The first thing that comes to my mind is Ian Kershaw, The End: Hitler's Germany 1944-45. Kershaw is a good Historian, an even better writer and the topic may be exactly what you're looking for. Also, the eBook is $9.51 at _URL_0_.",
"\"With Our Backs to Berlin: The German Army in Retreat 1945\" by Tony Le Tissier is a good book covering the Red Army's final advance into Germany. \"Armageddon: The Battle for Germany 1944–45\" by Max Hastings also covers the final battles of Nazi Germany.\n\n\n\"Hitler's Last Days\" by Anton Joachmisthaler covers Hitler's final days in the bunker, and deals with what happened to the people who were with Hitler in his final moments. \"The Nuremberg Trial\" by Anna Tusa is probably the most in depth book on the trials that one can get (and the ebook version is only 5$ on Amazon).\n\nFinally, \"After the Reich: The Brutal History of the Allied Occupation\" by Giles MacDonogh covers the allied occupation of Germany, with plenty of personal, first hand accounts. Also worth reading is \"The Russians in Germany\" by Norman Naimark.\n"
]
}
|
[] |
[] |
[
[
"Amazon.com"
],
[]
] |
|
1itfr7
|
what's the difference between a tube amp, solid state amp, amphead, stack, etc?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1itfr7/eli5_whats_the_difference_between_a_tube_amp/
|
{
"a_id": [
"cb7vfjo"
],
"score": [
2
],
"text": [
"A tube amp uses vacuum tubes in its amplifier stages. It supposedly has a warmer cleaner sound.\n\nSolid State amps use transistors or ICs for amplification.\n\nA hybrid amp uses both transistors and tubes. Most often a Hybrid amp uses tubes in the preamp section to get the warmth, a but a transistor/IC power amplifier for cost and efficiency. \n\nA combo amp is one that has the amplifier and speaker in one case.\n\nA stack has the amplifier and speaker as separate units, in which case the amplifier is called a \"head\" and the speaker a \"cab\".\n"
]
}
|
[] |
[] |
[
[]
] |
||
6czkgp
|
In the book 1421: The Year China Discovered America, it says they had colonies on Australian shores, how true is this?
|
When I search it up on google not a lot of information comes up.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6czkgp/in_the_book_1421_the_year_china_discovered/
|
{
"a_id": [
"dhynjmg"
],
"score": [
6
],
"text": [
"The frequently asked questions wiki page on this subreddit has a [section dealing with Gavin Menzies and 1421](_URL_0_). As you'll notice if you read the posts linked to in that FAQ, historians do not have a high opinion of Menzies. Also, an excellent [blog post](_URL_1_) by /u/mikedash - a quality contributor here - goes into quite a lot of detail on the trade networks that existed between China and northern Australia, and you may find that illuminating."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/wiki/historians_views#wiki_historians.27_views_of_gavin_menzies.27_.221421.3A_the_year_china_discovered_the_world.22",
"https://mikedashhistory.com/2016/10/31/dreamtime-voyagers-australian-aborigines-in-early-modern-makassar/"
]
] |
|
3zotja
|
why are vegans against dairy and eggs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3zotja/eli5_why_are_vegans_against_dairy_and_eggs/
|
{
"a_id": [
"cyntrk5"
],
"score": [
2
],
"text": [
"Yeah, it's generally because the cows and chickens and such that non-meat animal products come from are horribly mistreated. "
]
}
|
[] |
[] |
[
[]
] |
||
cco0wb
|
how is the scrotum able to react to temperature changes by tightening or loosening but when i’m in the shower with hot water running over them they still shrink if it’s cold.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cco0wb/eli5_how_is_the_scrotum_able_to_react_to/
|
{
"a_id": [
"eto67d1",
"eto698e"
],
"score": [
8,
141
],
"text": [
"The temperature range for ideal sperm production is actually quite narrow. The [cremaster muscle](_URL_0_) is responsible for lowering (cooling) or raising (warming) the testicles in an attempt to maintain that ideal temperature to keep the sperm healthy.",
"we have a cremaster muscle[ see here](_URL_0_) The cremaster muscle's function is to raise and lower the testes in order to regulate scrotal temperature . It does this by increasing or decreasing the exposed surface area of the surrounding tissue, allowing faster or slower dissipation of body heat.\n \nIn the shower the water and rubbing stimulates our cremastic reflex, The cremasteric reflex is a superficial reflex found in human males that is elicited when the inner part of the thigh is stroked. Stroking of the skin causes the cremaster muscle to contract and pull up the ipsilateral testicle toward the inguinal canal.\n\nHence our balls can shrink in the shower."
]
}
|
[] |
[] |
[
[
"https://en.m.wikipedia.org/wiki/Cremaster_muscle"
],
[
"https://en.wikipedia.org/wiki/File:Gray1143.png"
]
] |
||
2k26zu
|
When was the first recorded battle that used black powder or gun powder as a weapon? Did both sides have it? How crucial was it to the battle?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2k26zu/when_was_the_first_recorded_battle_that_used/
|
{
"a_id": [
"clhdrtg"
],
"score": [
45
],
"text": [
"I would say the siege of De'an in China in 1132 is the first recorded battle using black powder weapons. They employed what was called a 'Fire Lance' to shoot flames and shrapnel a few feet out from a bamboo tube attached to a spear.\n\nBlack powder as a weapon in other forms, like gunpowder arrows or javelins that burn or explode in fire, go back even further, maybe around the end of the Tang dynasty (900AD) but to my knowledge these finds or texts are not connected to specific battles."
]
}
|
[] |
[] |
[
[]
] |
||
kewy4
|
Observation in Quantum Mechanics? (How does the electron "know" it is being watched?)
|
I know that when you observe things on a quantum level the outcome can change, but I don't understand how or why. Is there a good explanation? Is there a good book on the subject for a general audience?
|
askscience
|
http://www.reddit.com/r/askscience/comments/kewy4/observation_in_quantum_mechanics_how_does_the/
|
{
"a_id": [
"c2jpuj8",
"c2jpw3j",
"c2jpyfj",
"c2js60z",
"c2jpuj8",
"c2jpw3j",
"c2jpyfj",
"c2js60z"
],
"score": [
9,
9,
6,
3,
9,
9,
6,
3
],
"text": [
"\"Observing\" is not the same as watching. In physics, the act of observation involves an interaction with the electron - for example, the electron hitting a phosphorous screen.",
"When you measure you need to do interact with the electron by doing stuff like throwing a photon at it. Watching the electron would amount to constantly bombarding it with photons to monitor its position.\n\n[This book](_URL_0_) by Expagnat is pretty good. Be careful buying books on this topic, there's a lot of garbage out there put out by the likes of Deepak Chopra.\n\n",
"Observer is a misleading term. It means \"something that forces the system into a specific state\" rather than \"dude watching it.\"",
"It's worth pointing out here that it isn't just the 'observing' of a particle that has an effect. This is at somewhat of a tangent but the Heisenberg uncertainty principle is a fundamental part of nature, not a limitation of equipment or our physics. It's been a long time since I went through the calculation but with high-level QM you can show that the position and momentum of a particle (or any two non-commuting properties) are not only unknown, they are unknowable. There's a common misconception that a particle will have a definite position and a definite momentum, even if we can't measure both. This is not true, the uncertainty principle means that the particle itself does not even exist in an unambiguous state.",
"\"Observing\" is not the same as watching. In physics, the act of observation involves an interaction with the electron - for example, the electron hitting a phosphorous screen.",
"When you measure you need to do interact with the electron by doing stuff like throwing a photon at it. Watching the electron would amount to constantly bombarding it with photons to monitor its position.\n\n[This book](_URL_0_) by Expagnat is pretty good. Be careful buying books on this topic, there's a lot of garbage out there put out by the likes of Deepak Chopra.\n\n",
"Observer is a misleading term. It means \"something that forces the system into a specific state\" rather than \"dude watching it.\"",
"It's worth pointing out here that it isn't just the 'observing' of a particle that has an effect. This is at somewhat of a tangent but the Heisenberg uncertainty principle is a fundamental part of nature, not a limitation of equipment or our physics. It's been a long time since I went through the calculation but with high-level QM you can show that the position and momentum of a particle (or any two non-commuting properties) are not only unknown, they are unknowable. There's a common misconception that a particle will have a definite position and a definite momentum, even if we can't measure both. This is not true, the uncertainty principle means that the particle itself does not even exist in an unambiguous state."
]
}
|
[] |
[] |
[
[],
[
"http://www.amazon.com/Conceptual-Foundations-Quantum-Mechanics-Advanced/dp/0738201049/ref=sr_1_11?ie=UTF8&qid=1315968277&sr=8-11"
],
[],
[],
[],
[
"http://www.amazon.com/Conceptual-Foundations-Quantum-Mechanics-Advanced/dp/0738201049/ref=sr_1_11?ie=UTF8&qid=1315968277&sr=8-11"
],
[],
[]
] |
|
2ratwq
|
Did an uneven distribution of wealth play a roll in the fall of the Roman empire?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2ratwq/did_an_uneven_distribution_of_wealth_play_a_roll/
|
{
"a_id": [
"cnebhaf"
],
"score": [
13
],
"text": [
"The reasoning behind this argument, for those who are unaware, is that the decline of freeholding citizen-soldier-farmers from the days of the Republic led to a decline in the Roman democracy, and eventually, to the Empire as 'barbarians' took over the ranks of the soldiery and undermined the 'Romanness' of the state. This is the classic argument Gibbon makes in the Decline and Fall, and it generally blames Germans, Christians, and rich slave-owners destroying the economy and army.\n\nModern historiography has moved away from this interpretation of both the economic and social causes of the fall of Rome, and instead tended to focus on the political. Peter Heather, one of those who is one of the staunchest critics of the Gibbon storyline, suggests that it was a combination of the rise of Persia, amalgamated Germanic tribes, and weak domestic political structures within Rome itself that helped lead to the 'fall'. He makes some very compelling arguments that suggest economically, although weakened thanks to a variety of factors, Rome still was chugging along in the 4th century relatively well considering all the turmoil, plagues, and contraction it had experienced in the prior century or so, but basically from around the 360s onward experienced a marked and rapid decline. \n\nI'd say most classicists tend to, like Heather, look for other rationale to explain this rather than blaming the Christians or Germans, whom, after all, had formed important parts of society for at least a few generations before the Empire really started to come apart. I don't see any particular reason why unequal wealth distribution need play a large role in that given that the Empire existed for a very long time with pretty much the same uneven distribution for most of it's final centuries."
]
}
|
[] |
[] |
[
[]
] |
||
eh52v1
|
before language was invented was an internal dialogue possible for humans? how would it have worked?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/eh52v1/eli5_before_language_was_invented_was_an_internal/
|
{
"a_id": [
"fcegxk3",
"fcei4qn",
"fcei9s1",
"fcej1sj",
"fcemgq3"
],
"score": [
2,
6,
2,
26,
3
],
"text": [
"That's an interesting question, and I doubt anyone can tell you since you'd need to experience it to know for sure, but I can tell you that this morning while it was still dark, I was stumbling into a bathroom, then in my mind's eye saw the contraption I was working on the day before and had laid on the floor, so (without any inner-dialogue) veered course to a different bathroom.\n\nThe big take-away on this is that language probably is what caused a big brain explosion in primates, especially humans, since suddenly there was a big demand, with huge payoffs, for understanding the meaning of sounds that others made. \n\nSo to answer your question more fully, before language, there would have been no place in the brain to process inner-dialogue. Why would there be?",
"keep in mind, things were a WHOLE LOT more simple when language wasn’t around.\n\nRoughly (and I’m no expert) it would’ve guttural noises and body language along the lines of\n\n\nEAT\nSLEEP\nRAVE\nREPEAT\n\nAs I said, I am no expert.",
"I'm not sure, but animals clearly have a thought process to make their day to day decisions. I suppose you could call that an internal monologue, although it wouldn't be words. Maybe a combination of sounds and pictures?",
"Yes. I can't tell you how it would have worked, but I am a speech therapist and I work with non speaking children and adults. Once they develop verbal language they can tell us that they had the same kind of thought functions as us, but it was produced more in concepts or pictures.",
"You can think just fine without language, and language can be decoupled from intelligence, as demonstrated by people with very low intelligence who are still exceptionally linguistically proficient (but everything they say is made up nonsense), and by people who are very intelligent but still can't speak due to e.g. brain injuries. Steven Pinker goes through a bunch of these arguments in his book *The Language Instinct*.\n\nCommunication between people is extremely slow and difficult without a complex language, but inside your head it isn't necessary."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
a3pelg
|
what is abductive reasoning?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a3pelg/eli5_what_is_abductive_reasoning/
|
{
"a_id": [
"eb7zw58",
"eb803le"
],
"score": [
3,
2
],
"text": [
"It is trying to figure out the best explanation for something without needing to prove it. Sort of trying to figure out the cause due to the effect.\n\nIt's not great for proving something is true, but can be helpful for finding avenues to explore. Think of troubleshooting a pc, if a screen is out we can deduce the cause through testing, but abduction would help us get ideas of where to start. \"is it plugged in? What did you do with it last time it worked? Have you hit restart? Etc.\n\nIn the end, abductive reasoning leads to\" well, this can cause the outcome we see. It's not for sure, but is one option\". ",
"It's kind of like Occams Razor.\n\nAbductive reasoning starts with an observation and comes to a likely, simplist, conclusion without positive verification. A \"probable\" conclusion rather than a definitive one."
]
}
|
[] |
[] |
[
[],
[]
] |
||
8sb34p
|
Why can’t we harness the Casimir effect as an energy source?
|
[Sixty Symbols- Casimir Effect and Black Holes](_URL_0_)
From what I understand it would not ever produce too much energy even if harnessed. Let me be clear I am a chemistry undergrad senior with only basic knowledge of physics, so please excuse my naïvety; but would it be possible to use plates with some sort of piezoelectric properties to convert the pressure differential between the inter-plate space and outer-plate space into an electric charge that could be exported to a battery? Or am I misunderstanding the kind of energy differential between those plates? The smart-ass sci-fi buff in me wants this to be a viable theory, but I’ve read countless times that there’s absolutely no way it could work; and i’ve always found the explanations lacking. Can anyone explain this one to me?
|
askscience
|
https://www.reddit.com/r/askscience/comments/8sb34p/why_cant_we_harness_the_casimir_effect_as_an/
|
{
"a_id": [
"e0yyg08",
"e0z3ddl"
],
"score": [
19,
13
],
"text": [
"It is just like any other potential energy. You can extract energy by moving conductors closer together. And then? If you want to repeat that you have to move them apart again, putting that energy back in.",
"It’s pretty much the same reason we can’t extract limitless energy from magnets or gravity. You would need to hold the plates at a fixed distance from each other, so that they couldn’t move, but you need movement to generate the electricity. It would be like trying to generate electricity from a pendulum that’s just sitting there being pulled down by gravity"
]
}
|
[] |
[
"https://youtu.be/IRcmqZkGOK4"
] |
[
[],
[]
] |
|
aztebp
|
why do the tv shows produced by local stations on a budget look so terrible, while those produced by hbo/netflix/etc look so good? how exactly does the extra budget money make them look so much better?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/aztebp/eli5_why_do_the_tv_shows_produced_by_local/
|
{
"a_id": [
"ei9wxpu",
"ei9wzbx",
"ei9xx66",
"ei9yzl5"
],
"score": [
14,
8,
5,
3
],
"text": [
"It funds better lighting, and cinematography instead of just video recording. Using much more expensive cameras and knowing what you are doing produces vastly better results than a local station can afford for Good Morning {Name of Town}.",
"Better lighting equipment, better cameras, better props and sets, etc. All of that stuff comes in a variety of quality, and the higher quality costs money. So do experienced and skilled crew members (to rig up lights, operate cameras, etc). There's also the ability to afford filming on location instead of on a set and the ability to afford more takes and reshoots when the first attempt doesn't look good.",
"Everything the others have said, plus a dedicated ***editing / post-production team***.\n\nGood equipment will get you good raw footage, and a skilled editing team can stitch it all together real nice and flowing, by e.g. accurately cutting out bad footage, putting well-timed transitions in, blending video and audio effectively, putting in overlays and effects, etc.\n\nWith smaller budgets / when it's just Dave trying to put it together overnight, you are often forced to leave out a lot of these refinements, resulting in a final product that is often 'rough around the edges'\n\n*Edit: ELI5-ised*",
"More money means you can hire experts who charge more for their services. You can also hire more of them, and you can keep them working longer.\n\nYou can also afford to do things like “build sets” or “travel somewhere pretty” instead of shooting in whatever you can find around town."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
bv3cgv
|
How common were dinosaurs?
|
It sounds dumb but hear me out. In movies, we always see dinosaurs in a mass quantity, squished together and nearly on top of each other. But if we were to go back right now, how often would you see dinosaurs? What would be the density of dinosaur life? What modern day animal sightings could you compare dinosaurs with? I really hope this question makes sense, but I can elaborate more if I have to. Thanks!
|
askscience
|
https://www.reddit.com/r/askscience/comments/bv3cgv/how_common_were_dinosaurs/
|
{
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"epp7pp4",
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86,
9,
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"text": [
"Dinosaur were weird. Their maturity curve was very different from mammals and more like fish. Mammals, especially large ones, usually produce one or two offspring at a time and these grow rapidly to adult size with help from a rich starter diet of milk. Dinosaurs, in contrast, produced tons of offspring at a time and grew more gradually. So you would expect to see fewer big dinos and a lot of little ones. \n\nAnother thing to keep in mind is that modern ecosystems are very sparse in large animals due to human influence. Not so long ago other parts of the world matched the diversity of subsaharan Africa.",
"The basic functions of life hasn't changed from prehistoric eras to today. Things need calories, water, oxygen (generally) to live. They need to live long enough to procreate. Species that are not efficient at procreation die. There was a \"food web\" with a hierarchy. Lots and lots of smaller critters (predators and prey), some in the middle and a few alpha predators. Variations in climate, weather, and minor to major events had impacts on the local, regional and global life. The generic predator/prey model would have existed then, as it does now.\n\nIt would make sense that prehistoric eras had similar distributions of animals and plant life that we find in various parts of wider wilderness. So savanna to jungles to desert to temperate forests, etc. Not to mention the different regions for aquatic life. The key difference is the number of the species in flora and fauna would be highly dependent on the era that we're talking about.\n\nGo for a walk in the woods (not sure where you live) and you will see (which is only tangentially related to actual population counts) lots of flying things (which may, or may not have existed in some pre-historic eras), lots of small (insect size) things, a few small ground animals (rodents, reptiles, amphibians, for example), and fewer larger animals (deer), and very rarely top predators (big cats, bears etc) if at all. It did depend on the oxygen concentration though, which did vary a lot over the age of life on Earth. Also large variations depending on the seasons and mating cycles, etc.\n\nThere where a number of very large extinction events that wiped out large numbers of life. This would have, effectively, de-populated large swaths of land and ocean. It takes many millions of years for new animals to evolve to occupy those niches. About 125M years between the Late Devonian extinction (75% lost) and the End Permian (96% lost).\n\nThe speculative part is that, for example, the Triassic period still had 1 massive land mass in Pangaea. Also remember that the break up of Pangaea took millions of years. So the distribution of life would have been in some flux. I would think that this would have happened slow enough that animal life would have evolved along with it.\n\n & #x200B;\n\n[_URL_1_](_URL_1_)\n\n & #x200B;\n\n[_URL_2_](_URL_2_)\n\n & #x200B;\n\n[_URL_0_](_URL_0_)\n\n & #x200B;\n\n[_URL_3_](_URL_3_)",
"We know about social behaviour through tracks, by and large as well as groupings or solitary fossils. We have found tracks of herds of herbivores, some even mixed in species as to protect against predators. It is safe to assume that herbivores weren't always solitary, and perhaps like elephants where females and young males herded while males wandered. Could also be like deer, where a strong male keeps a harem until either he dies or is defeated by another. Places where multiple skeletons are found in proximity hint towards this. \n\nPredators, however. Their tracks found have been largely solitary, especially in larger species. Smaller ones however can be grouped, most notably (popularly) among the raptor family but it can also be found in other small theropods. They pack like wolves, using the strength of numbers to hunt more effectively. We do, however, have situations like crocodilians where they can be living with some density but not necessarily social or pack hunting. It is safe to assume that breeding pairs might stay together a short time, like other generally solitary species, but by-the-by are solitary, perhaps stalking herds of herbivores in wait for an individual to stray a little too far away.",
"Be wary about which movies you use as reference. *Often* Hollywood ignores the science or experience of the consultants they hire to help build accuracy. Aside from the *Jurassic Park* franchise, most dinosaur films are cartoons and gimmicky cash-grabs. In regards to the films based on Michael Crichton's books, remember that if the attractions at any theme park were spread out over miles, it would be a far more boring outing. Disney World is only about 8.5 miles worth of main walking paths through all four parks. If Jurassic Park had been set up like a real world game reserve that is well known for amazing animal views like the Sabi Sand Game Reserve in South Africa it would take several hours at a time in a vehicle to see anything, instead of just a few on a curated route to see a lot. Keep in mind that reserves can be extremely tiny at fractions of a square mile up to Sabi Sand at 250 sq/mi and Kruger National Park that spans three countries and 8.2M sq/mi, while Disney World is 47 square miles and a third of that is set up as conservation, and the whole island of Isla Nublar that housed Jurassic Park was only 30 sq/mi and only about half of it was set up as the park.\n\nInstead of *Jurassic Park* or *Jurassic World*, take a look at *The Lost World: Jurassic Park* (2) where the animals are living without paddocks and it takes time, even hours, between sightings or encounters.\n\nSo, more than likely, about the same density as in the wild and on reserves as you would see today, with specific animal size taken into account.",
"The classic Hollywood scene of hundreds of different species of dinosaurs all gathered in a huge communal nesting ground while bombastic music soars is a little exaggerated.\n\nBut when people say things like, \"Dinosaurs ruled the earth\" they really mean it. The majority of macroscopic life you would see walking around during the Jurassic/Cretaceous/etc would have been dinosaurs. In the same way that most life you see walking around today is mammalian.",
"The age of dinosaurs was akin to how the age of Mammals is now. Some species stuck together and some lead a solitary life. They also would have used different behaviors in hunting. Some animals would be regularly visible and and surround themselves with other species and some would ambush so they wouldn’t really be something you would notice."
]
}
|
[] |
[] |
[
[],
[
"https://www.factmonster.com/dk/encyclopedia/science/era-dinosaurs",
"https://ucmp.berkeley.edu/mesozoic/triassic/triassictect.html",
"https://www.livescience.com/43295-triassic-period.html",
"https://cosmosmagazine.com/palaeontology/big-five-extinctions"
],
[],
[],
[],
[]
] |
|
1hdv84
|
Did people from the Medieval time period consider themselves living in "Medieval" times, or was it something titled by modern historians?
|
Did people from the Medieval time period consider themselves to be in the Medieval time period?
Or did modern historians create that word to describe that time period? If so, why/how/when did they choose that word?
Similar questions for people living in "The Dark Ages."
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1hdv84/did_people_from_the_medieval_time_period_consider/
|
{
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"catjbc3",
"catn1qd"
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"text": [
"Reference to the Middle Ages first enters Latin in 1469, and the tripartite periodization with which we're familiar today became the standard way of thinking in the seventeenth century thanks to Christoph Cellarius, although Leonardo Bruni was the first scholar to do so in his *History of the Florentine People* (1442). I'm sure periodization would have differed by country in medieval times, but I am aware that Petrarch referred to pre-Christian times as *antiqua* and the present period as *nova*, suggesting that some medieval thinkers had the same conceits as we do today *vis-à-vis* considering ourselves or our society *modern*.",
"Medieval people emphatically did not think of themselves as living in the “middle” of anything. (In some of its many eras, some people thought they might be living at the “end” of time—as did early Christians, who expected the end of the world and return of Jesus as any moment.) By the late 11th century they have a clear sense of progress and the potential for the “reformation” of society. They could likewise project themselves into the future. Thus, the Gothic cathedrals of the late 12th century onwards were started with the realization that it would usually take several generations to complete them. They nonetheless had a clear sense of their indebtedness to the past. In the mid-12th century John of Salisbury reports that his teacher Bernard of Chartres used to say: “We are like dwarfs standing on the shoulders of giants; if we see farther than they did, it is because we are lifted up by them” (I’m paraphrasing the second clause a bit—too lazy to look it up!). In short, they thought of themselves as “modern” as you do.\n\nSo how did they become the “Middle Ages”? We can look to the Renaissance scholars' sense of what they had achieved: a “rebirth” of ancient culture (the literal meaning of the French phrase “Renaissance,” coined only in the mid-19th century, though people like Georgio Vasari spoke of a “renascita” or rebirth of art in the mid-16th century). Renaissance thinkers needed to explain why interest in Greco-Roman antiquity and its literary products had languished for a thousand years. (It really hadn’t, but that’s another thread.) That stagnant gap between the ancient culture they adored and themselves was a “middle era,” a *medium aevum* according to the German legal historian Melchior Goldast, who coined the phrase in 1604. Just as “turtleeatingalderman” says, in the 14th century Petrarch had already spoken condescendingly of the era before him, a period of “darkness” and Vasari gave us the phrase “Gothic art” as a disparaging way to refer to medieval art—the art of Goths or barbarians. (The wonderful irony this dissing of the MA is that when Renaissance scholars went looking for ancient Latin works, they found them in monasteries often preserved in 9th-10th-century Carolingian manuscripts. The clear bookhand in which they were written, so different from their own crowded script, made them think they had discovered books actually written by the ancients. Instead, they owed what they found to Carolingian scholars as interested in classical works as they were.) \n\nSir Henry Spelman (c. 1564-1641) first used the phrase “the Middle Ages” in English in 1616. In 1675 the Dutch professor Christoph Keller (“Cellarius”) popularized “*medium aevum*” in his textbook, *The Nucleus of Middle History between Ancient and Modern*.\n\nAs the Enlightenment dawned (sorry, couldn’t resist), the libel against the backwards and “superstitious” Middle Ages further evolved, since it seemed to be an age irrationally enthralled with spiritual delusion and tyrannical government, two things enlightened thinkers despised. Thus, early in 1715, in his *Essay on Manners and the Spirit of Nations* (one of the first works of social history) Voltaire thought it necessary “to know the history of that [middle] age only in order to scorn it.” The same applied even to the 15th century, where for him, “Barbarism, superstition, and ignorance covered the face of the earth, except in Italy.” In 1776 in his *Decline and Fall of the Roman Empire*, Edward Gibbon wrote: “The darkness of the middle ages exhibits some scenes not unworthy of our notice,” but notice that grudging “some scenes” in an otherwise dark period. The idea of a dark Middle Ages gets enshrined in Jacob Burckhardt’s, *Civilization of the Renaissance in Italy* (1860), which really popularizes the idea of a bright Renaissance contrasted with a dark Middle Ages that preceded it. Here’s his take on the Middle Ages:\n\n > In the Middle Ages both sides of human consciousness—that which was turned within as that which was turned without—lay dreaming or half awake beneath a common veil. The veil was woven of faith, illusion, and childish prepossession, through which the world and history were seen clad in strange hues.\n\nSimultaneously, however, the Romantics were rediscovering the spiritual attractiveness and “emotive qualities” of the Middle Ages while Romantic nationalists were exploring their medieval histories as a way to instill national and ethnic pride. The Middle Ages began to get some respect!\n\nHistorian Brian Stock summed up the evolution of the Middle Ages in a famous quote: “The Renaissance invented the Middle Ages in order to define itself; the Enlightenment perpetuated them in order to admire itself; and the Romantics revived them in order to escape themselves. In their widest ramifications, then, ‘the Middle Ages’ thus constitute one of the most prevalent cultural myths of the modern world.” (*Listening for the Text: On the Uses of the Past*, p. 69, from which I’ve pulled some of my info.)\n\nIt’s worth noting that the phrase “dark ages” gets a different emphasis from the Catholic historian Caesar Baronius in the late 16th century, where he uses it to refer to the early Middle Ages (say 400-800) for which in his day there was little available written evidence, so they were cloaked in “darkness.” We use that same phrase to refer, for example, to the Greek “dark ages” between 1100 BCE and 750 BCE for which there is scant written evidence and also for Anglo-Saxon England where there is little record of c. 400-500.\n\nEDIT: Proofreading as usual. Had to close a parentheses."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2sp3w6
|
how does the curiosity rover take pictures of itself?
|
When looking at pictures like [this](_URL_0_) it appears there is nothing attached to the rover itself that is taking the picture.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2sp3w6/eli5how_does_the_curiosity_rover_take_pictures_of/
|
{
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"cnrl2st",
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"score": [
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"text": [
"I won't be able to explain any better, so have a look here: _URL_0_",
"I'm trying to post you this link but the stupid automoderator of this sub has removed my post so here I am writing a lengthy sentence in the hopes that it will not detect lack of content and delete it. The following link contains a video that will explain to you how Curiosity took its selfie.\n\n_URL_0_\n\nNo offence but at this rate they should rename the sub /r/lmgtfy",
"By utilising [advanced technological equipment designed specifically for this purpose] (_URL_0_)"
]
}
|
[] |
[
"http://i.imgur.com/2aWKxtd.jpg"
] |
[
[
"http://www.nasa.gov/mission_pages/msl/multimedia/pia16457.html#.VLnNJHXcdhE"
],
[
"http://news.nationalgeographic.com/news/2012/121204-curiosity-mars-rover-portrait-science-space/"
],
[
"http://en.wikipedia.org/wiki/Selfie_stick"
]
] |
|
u05hb
|
What was the most advanced society relative to the rest of the world?
|
Probably been asked before, and more probably a simplistic take: the Egyptians were architects extraordinaire, the Chinese had super weaponry hundreds of years before the rest of us, and Greeks as well as Muslims and Hindus (not sure what to call the respective cultures) were mathematically ahead of everyone.
What civilization was the furthest ahead of the rest of the world in technological advancements?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/u05hb/what_was_the_most_advanced_society_relative_to/
|
{
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"c4r7evr",
"c4rh5ws"
],
"score": [
4,
8
],
"text": [
"What time period are you talking about? The most technologically advanced societies would be today's societies. 3000 BCE- 600 BCE- 0 CE- 600 CE- 1450 CE- 1750 CE- 1914 CE- Present have a lot of power shifts and history going on between them. If you are talking about Ancient (3000 BCE) society then probably Egypt, having the organization / manpower to build their pyramids, etc. By 600 BCE it s probably the Persians (my best guess, not an expert) by 0 CE it is the Roman and Han empires (Rome absorbed a lot of technologies and achievements of conquered civilizations, and the Han had a well educated meritocracy, as well as many of their own inventions), between 600 CE and 1450 CE Dar Al Islam was expanding and building up massive trade networks as well as higher education facilities, but by 1450 The Europeans were doing a lot of Sea trade, particularly Spain, Portugal, the dutch, British, French, and some others, using wealth and seafaring technology other places didn't have. by 1763, The British were poised as the most powerful nation in the world at the conclusion of the seven years war, remained so throughout 1914, and jump started the Industrial revolution. After WWI, the British were severely weakened, and by WWII, The Americans and Soviets were the most powerful and advanced nations, with nuclear weapons and other military, as well as technological (computers) advancements unprecedented.",
"8000 years ago, the people of the Hilly Flanks in southern Anatolia has agriculture, and nobody else did. That is a pretty big difference."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3r6zvb
|
the speaker of the house is not nonpartisan?
|
I've noticed that the new Speaker of the United States congress (Paul Ryan) listed repealing Obama care as one of his top priorities, which seems incredibly partisan to me. In Canada (where I live) the speaker of the house (federally) and of the legislatures (provincially) are usually nonpartisan and don't push specific legislative agendas. Is this not a thing for the U.S? Why is this? How does this role differ in the U.S and Canada? (Posted here cause r/politics doesn't allow text)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3r6zvb/eli5_the_speaker_of_the_house_is_not_nonpartisan/
|
{
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"cwlggi4",
"cwlh19b"
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5
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"text": [
"The Speaker, in the U.S., is usually a major figure in the majority party and is usually partisan (at least recently). In fact, Boehner's relative willingness to compromise was a big part of why he had so much trouble getting the Republicans in line.",
"The Speaker of the House in the Westminster system is a non-partisan figure who is there to ensure the rules of the House are followed, and to allow debate.\n\nThe Speaker of the House in the American system is the leader of the largest party (similar to, but not same as, a Westminster Prime Minister). They set the agenda, and actively work to push the polices of their party through."
]
}
|
[] |
[] |
[
[],
[]
] |
|
32s6g4
|
inflammation and atherosclerosis
|
Contemporary medical research is focusing a lot on diet-induced inflammation, and how this may be the leading cause in ailments such as atherosclerosis.
What I have not understood, is the mechanism behind this inflammation? How do the arteries get inflamed? A chemical 'irritates' the cell walls? If so, how? If not, then how?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/32s6g4/eli5_inflammation_and_atherosclerosis/
|
{
"a_id": [
"cqe93ag"
],
"score": [
2
],
"text": [
"The basics of this are that inflammation occurs when cells are damaged, the source of damage doesn't matter but when a cell IS damaged they release chemicals that cause inflammation.\nAtherosclerosis is also a process based in cell damage. Your blood always has a certain amount of circulating cholesterol which is perfectly normal and flows along with everything else, but when the lining of an artery is damaged cholesterol molecules enter under the first lining layer and form a little plaque, basically thickening the point to stop it being damaged again.\nThere are some theories bouncing about that fat in your diet doesn't cause atherosclerosis because it doesn't cause the damage, yes it means more cholesterol circulating in the blood but not more deposits. Sugar is now getting a lot of flack as high levels for glucose in the blood can cause damage to the lining of the arteries."
]
}
|
[] |
[] |
[
[]
] |
|
3z6alj
|
possible solutions to xeno's paradox
|
Could anyone ELI5 the possible solutions to Xeno's Paradox? In case you may be unfamiliar with it, it is a series of paradoxes developed by the ancient Greeks. Essentially, it is states that moving from point 'A' to point 'B' is physically impossible because you must pass through an infinite series of midpoints.
For example, to go a distance of 10 miles, you must first travel 5 miles. To reach 5 miles, you must travel 2.5 miles. To reach 2.5 miles, you must first travel 1.25 miles and so on to infinity. Thus, as you must traverse infinite midpoints, travelling 10 miles should not be possible...yet we do it all the time...
Does anyone know if there is a ELI5 solution to the paradox?
Thanks!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3z6alj/eli5_possible_solutions_to_xenos_paradox/
|
{
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"cyjjgmh",
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"text": [
"The solution is that at the same time you're halving distance, you're also halving time. So while you have an infinite number of steps, most of them take an infinitesimal amount of time.\n\nYou could state Xeno's Paradox the other way as well: you're traveling distances in effectively no (or, at least, infinitesimal) amounts of time, so all movement is teleportation!\n\nThis should seem obviously silly - and it should seem as obviously silly as the notion that you can never move anywhere because you have to move half the distance first.",
"Zeno's paradox relies on the implicit assumption that it takes an infinite amount of time to cross an infinite number of points, but this clearly isn't true - the time taken is proportional to the distance, and when you divide up the distance in the manner proposed you are *also* dividing up the time, so that the total amount of time to travel the 10 miles doesn't actually change (as you would expect).\n\nSuppose you travel at 10mph. It takes you half an hour to travel the first 5 miles,1/4 of an hour to travel the next 2.5 miles, 1/8 of an hour to travel the next 1.25 miles. How long does it take to travel the full distance? Well, that's equal to the infinite summation:\n\n T=0.5+0.25+0.125+0.625+...\n\nNow we can multiply both sides by 2: (yes, I know this is not rigorous)\n\n 2T=1+0.5+0.25+0.125+... \n 2T=1+T\n T=1\n\nSo it takes 1 hour to travel 10 miles at 10 miles an hour, exactly as you'd expect. The introduction of an infinite division of space doesn't change the result. The idea that an infinite series can have a finite sum didn't exist in Zeno's time - it took the development of analysis to give a proper treatment of such summations."
]
}
|
[] |
[] |
[
[],
[]
] |
|
6ud970
|
Aliens, Bigfoot, and Ghosts? What's the history of "the paranormal" in Western thought?
|
I heard about John Murray Spear and his attempt to build a "New Motive Power", so I was curious, what is the history of what we would roughly call "the paranormal" (by which I mean things like aliens, UFOs, ghosts, cryptozoology, ancient aliens, ESP, etc.) in Western thought?
When did they become the paranormal for that matter? When did we start breaking up the world into natural and supernatural in such a way that there could exist a place for the paranormal and when did certain content fill the place of the paranormal?
How have groups promoting the paranormal changed over time? What in-depth studies have been done on them? What have their key moments been?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6ud970/aliens_bigfoot_and_ghosts_whats_the_history_of/
|
{
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"dlsmjqx"
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"text": [
"An interesting case study would be the Loch Ness Monster; a creature attested as far back as St Columba's early medieval hagiography before its resurgence in the mid 20th century. As we'll see, shifting cultural and scientific paradigms completely altered the ways in which people from the same geographical location \"constructed\" their monster.\n\nTo pre-modern Europeans, a monster’s physical form was significant because its composite parts or overall bodily shape held some kind of metaphorical or allegorical significance. Whether their forms were interpreted by pagans or Christians, animalistic monsters seem to have been more important as vehicles of symbolic meaning than as flesh-and-blood entities to be found in the wild. Many believers in the Loch Ness Monster regularly cite the existence of similar creatures in early medieval Irish hagiographical literature, notably the Life of Saint Colum Cille, who banished a reptilian monster in the River Ness adjacent to the Loch, as historical evidence for the existence of some prehistoric creature. I will briefly situate these occurrences within the symbolic rather than scientific pre-modern worldview to highlight the allegorical significance of monstrous animals. Dáithí Ó hÓgáin’s article “’Moch Amach ar Maidin dé Luain!’” explains that reptilian lake monsters are a surprisingly common trope in early Irish secular literature, hagiographies and oral tradition; in each instance, a monstrous reptilian creature terrorizes the nearby countryside, devouring livestock before being challenged and slain by a hero (whether he be a pagan warrior or Christian saint), turning the lake red with its blood. Ó hÓgáin explains that this trope may be the synthesis of several forms of symbolism where the reptilian lake monster represented paganism enslaving the Irish population before being routed by the powerful Christian saint (which popular tradition concretized from a metaphor to a literal representation of a monster) while the dramatic narrative of martial heroes overcoming lake monsters predates hagiographical sources, suggesting pre-Christian origins.\n\nSerpents appear to have held important symbolic significance in pre-Christian Celtic art. Because of their ability to disappear into impossibly small crevices beneath the ground, regular shedding of their skin and incredible reproductive capacities and movement which mimics the meandering of slow-moving waterways, snakes were likely associated with the underworld, fertility and regeneration by pre-Christian Celtic speakers. Celtic societies regarded bodies of water as liminal spaces between a supernatural otherworld and the physical world (explaining the overwhelming amount of votive offerings found across the Celtic speaking world in bogs, streams, rivers and lakes), meaning that the combination of the otherworldly serpent with the liminal space between worlds would have had a significant symbolic meaning to pre-Christian Celtic speakers. In such a cosmology, the lake serpent would have represented a believable manifestation of otherworldly power on earth, and its defeat by a mortal hero would have accentuated his martial prowess, an important concern in a society dominated by a warrior-aristocracy. In this context, the physical existence of the lake monster would have been less important to the pre-Christian and early Christian audience than the respective symbolic meaning that it represented; the overcoming of a powerful otherworldly entity by a mortal warrior-hero and the overcoming of pagan influence by a virtuous saintly hero.\n\nSimilar, later Christian monster narratives used their subject’s bodies as vehicles to convey symbolic meaning. Using ancient Greek compilations of marvels and wondrous creatures, St. Augustine laid the foundations for the medieval genre of Bestiaries by demonstrating God’s power through the existence of seemingly impossible natural creatures, with the added goal of compelling believers into marvelling at God’s creation. Like modern believers in monsters, medieval Europeans did not consider monstrous animals as ‘unnatural’ (or contra naturam) but instead considered them ‘natural’ members of God’s creation who were intended to relay some kind of symbolic meaning to those who viewed them as Isidore of Seville explained: “portents and omens [ostenta], monsters and prodigies are so named because they appear to portend, foretell [ostendere], show [monstrare] and predict future things… for God wishes to signify the future through faults in things that are born…” One was not required to personally witness such a monster to glean symbolic meaning from its form or behaviour as medieval Bestiaries listed fantastical creatures alongside more mundane ones with a moral lesson in each entry; descriptions of mermaids drawing in sailors to their dooms were meant to teach that one should always be wary of flattery. \n\nModern observers, it seems, are obsessed with the physical composition of their monsters not because their composite parts may reveal some portentous symbolism, but because the post-19th century western episteme forces them to rationalize the existence of their monsters within a scientific context. This change came about in an astonishingly short amount of time – it took only some four decades of scientific research, analysis and theorization to completely change the West’s understanding of the natural world, the creatures that inhabited it, and their own relationship to both. The scientific fields most crucial to this intellectual revolution were the sister disciplines of geology and palaeontology, as a rapid succession of discoveries in both completely challenged the established episteme. \n\nHow was this episteme established? I don't think it's necessary to provide a play by play of the intellectual revolutions of the early modern era and 19th century, but to give you a short run down; in the late 18th century a French savant named Georges Cuvier published a paper detailing his studies of fossil mammal species which proved that at some time in the earth's history, distinct and separate species of rhino, elephant, deer etc. had roamed the planet before going extinct. Though his discover may seem trivial today, Cuvier’s suggestion was an absolute paradigm shift. By demonstrating that long-lost species of animals had once roamed the earth possibly tens of thousands of years in the past, Cuvier had challenged the conventionally accepted Creationist worldview which purported that the earth was only several thousands of years old, and that all the planet’s creatures had been present since Creation. Cuvier further complicated the traditional worldview when in 1824, he named and described several hitherto unknown fossil species found in the Maestricht fossil beds: ichthyosaurus, a fish-like marine reptile; mosasaurus, a large crocodilian marine reptile and pterodactyl, a species of birdlike flying lizards. Plesiosaurus, a large predatory marine reptile notable for its small head atop a long serpentine neck was also discovered in that year, and as I will describe below, provided the visual template for lake monsters such as the Loch Ness Monster. These discoveries laid the ground for a profoundly new conception of historical time: that the earth and the organisms that inhabited it were not static but were subject to some sort of change, and that completely alien forms of life had preceded all kinds of currently existing plants and animals by thousands of years. "
]
}
|
[] |
[] |
[
[]
] |
|
2h3hpc
|
Did Hitler have anything to say about 'Mein Kampf' and its contents after he finally rose to power? Did he ever make any attempt to revise, expand or alter it?
|
And did he ever try to write another book?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2h3hpc/did_hitler_have_anything_to_say_about_mein_kampf/
|
{
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"text": [
"Hitler did actually try and write another book. Its been called Zweites Buch or \"Second Book\", where as Mein Kampf focused on Hitler's early life and struggles as well as setting the tone for Nazi racial politics, the Second Book focused on foreign policy and what the Nazis plans were for their neighbours. The book sets out step by step what the Nazi's plans were and how they planned to accomplish them. It talks about the alliance with Italy, the alliance with Great Britain that Hitler hoped would happen, and the plans to deal with the Soviet Union. The book deviates near the end and goes into a sort of alternate history, where Hitler talks about the future of the Nazi state and what will most likely happen when the Nazis achieve total domination of Europe. Hitler envisions that a German dominated Europe and the British Empire will fight an almost cold war like struggle against the United States. \n\nThe book was written in 1928 after Mein Kampf, but it was never published for two reasons. One, mein kampf flopped and thus Hitler never bothered publishing his second work. And two, the Nazis were strapped for cash and Hitler was told to hold off from releasing another book, lest he spoil the market and alienate the few people who were buying his books. Historian Gerhard Weinberg would later publish the unreleased book in his own book called \"Hitler's Second Book: The Unpublished Sequel to Mein Kampf\". I find that today, most copies of Mein Kampf will include both books together, because they really are meant to go together. ",
"In Albert Speer's memoirs he says this about Hitler when he was chancellor.\n\n\"Politics, for Hitler, was purely pragmatic, He did not except his own book of confessions and professions, *Mein Kampf*, from this general rule. Large parts of it were no longer valid, he said. He should not have let himself be pinned down to definite statements so early\"\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
59is37
|
how does shampoo and body wash work so effectively when it only stays on our body for a few seconds before getting washed off?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/59is37/eli5_how_does_shampoo_and_body_wash_work_so/
|
{
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"text": [
"If I understood correctly, you are basically asking how soap works. \n\nSoap/shampoo/body wash has molecules that can interact with both the water and the fat/dirt you want to remove. These molecules have a polar portion, which binds them to water, and an apolar portion, which makes them able to interact with organic matter (fat, dirt, basically what you want to remove when using soap). So in a way, soap allows the organic matter (dirt) to become \"soluble\" in water. You're not really destroying the dirt molecules per se, as much as allowing them to be washed away and go down the drain.",
"[There's a Magic Schoolbus Episode featuring Wynonna Judd about this.](_URL_0_)",
"In addition to the above comments, friction also helps. \nLike when you wash your hands with alcohol rub, or soap and water, it's friction doing a lot of the work along with the soap/alcohol rub. ",
"Dirt on your skin and water that you use to wash up with are like your two pointer fingers. Shampoo/body wash/soap are like a Chinese finger trap. When you get all three of these things in the same place at more or less the same time, you'll eventually have the Chinese finger traps trapping the dirtfinger with the waterfinger.\n\nThe only difference is that the waterfinger is stronger and rips off the dirtfinger to go down the drain.",
"Am I weird for having it in a couple minutes instead of \"seconds\"? Does it actually work in just seconds?",
"Soaps are surfactants, and a surfactant is a substance that is both soluble in oil and water. Normally oil and water dont like to mix, hence why salad dressings will always reseparate after shaking them. Oil is not soluable in water, unlike something like salt that dissolves really easily. Surfactants make oil more like salt, more easily dissolved into water and more easily washed away.\n\n\n\n\nSidenote: Surfactants are also necessary for humans to breathe since they take away surface tension from water. Your lungs are basically a bunch of little deflated balloons the need to fill with air. But since there's a little bit of water on the inside of these balloons, the balloons have trouble inflating since the sides are stuck together, sort of like wearing a wet t-shirt and trying to pull it away from your skin. Surfactants break surface tension, making it easier for the sides of the balloon to separate. \n ",
"I think OP isn't asking how soap works but rather, why we have to wait a little before rinsing(?) the shampoo",
"Like stated above, it has to do with the polarity of the molecules which allows them to essentially become \"Slippery\" and wash/slide off your body. \nIt seems to happen so quickly because it's a polarization reaction, much like that of a magnet. The same reason the soap only takes an instant to work in most cases can be understood much like a magnet, they instantly polarize when placed near a material with which they can interact. \n\nSomething about hand washing I learned in Medical school is when it comes to getting your hands clean of pathogens and other potentially infectious materials, running water (as opposed to a basin of water), along with friction is far more important than actual soap. \n\nHope that could help clear up some confusion for you. \n\n"
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=w4tkp6ieldw"
],
[],
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[],
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||
8k810h
|
are there any benefits to regressive taxation? has it ever been used?
|
Hey! I'm currently taking econ in high school and have been reading into the different forms of taxation. I find regressive taxation to be quite fascinating because of it's inherent awfulness (tax more to the poor, less to the rich). When doing research online I haven't found a single example of a country actually using it or it's benefits, and I'm curious if there are any. What's the point of learning about regressive taxation if it's not even a real-world thing?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8k810h/eli5_are_there_any_benefits_to_regressive/
|
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"text": [
"There are many forms of regressive taxes in common use. Sales taxes, for example, are regressive, which is why food is often exempt from them.",
"Not much of a thing anymore. Basically all of serfdom was a regressive tax, at least how it’s portrayed. A possible reason for regressive taxation is that the majority of the population is poor, and the wealthy, elite citizens need the money to improve everyone’s lives. \n\nAlso, it’s feasible that the vast majority of people could be considered “rich” and only a small fraction be considered poor. If the majority of a culture has power, they may use it to oppress the minority. \n\nAs far as a possible use in the United States, unlikely. I could see us getting to a proportional tax system, with maybe some extra deductions for the really poor (something like that). \n\nSchool is about learning how to think, not about facts and figures in the real world. Understanding the three tax systems is just a way to think about ethics, economics, math, and culture. You’re doing a good job of it by looking for the pros and cons of each, even though you dislike regressive taxation. ",
"The US has a regressive tax system for very rich people. Almost all of my income is capital gains which are taxed much less than income. I give lots to charity which lowers it still more. There are other tricks besides (legal ones I mean). \n\nIt may not be fair, but it's the system we have. ",
"Not an expert on this, but French nobles are exempt from tax such as taille in the old regime, before the French Revolution of 1789. I don't really know why this is, but my guess is that it has to do with the social hierarchy and class system from medieval Europe.\n\nedit: I thought about it a bit more and it makes sense that monarchs will be inclined to tax peasants and not the nobles.\nMonarchs, even absolute monarchs like Louis XIV, needs support from certain key people. People like finance ministers and military leaders. These are the people that can overthrow a regime if they really put their mind on it. To stay in power, the ruler must keep these people loyal and happy. A tax break is a simple way to give favors to these important people to keep them loyal. \n\nNow peasants are another story. They often labor in the fields for the entire day and are uneducated. These are the people who are going to have a seriously hard time challenging any regime. Looking at peasant revolts like German Peasant War in 1525 or Pugachev's Rebellion in 1773, they all got harshly suppressed by the monarch. This is because the monarch still had the support of the nobles, meaning they are able to put down these rebellions. Successful revolts, like the French Revolution and English Glorious Revolution, are organized by the Middle or Upper class and often had the support of the military. This means as long as the peasants aren't dying, the ruler can put a heavy tax on them since they do not have a significant impact on the regime.\n\n\nTLDR: Tax breaks for Nobles because they are important; heavy tax on peasants because they couldn't do anything about it.",
"Regressive income tax is basically non-existent but many sales and excise taxes end up being regressive due to the marginal utility of money. The more money you earn, the less each dollar is important to you, and the less likely you are to spend it. On the flip side, the less you earn, the more important each dollar is and you become more likely to use it to purchase necesities. \n\n"
]
}
|
[] |
[] |
[
[],
[],
[],
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[]
] |
|
1btkn4
|
the challenger (space shuttle) crash.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1btkn4/eli5_the_challenger_space_shuttle_crash/
|
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"text": [
"The Challenger disaster was technically a structural failure leading to an explosion. It was caused by a design flaw in the solid rocket boosters (SRB's) which are the two big white rockets stuck to the outside of the big orange tank (look at a picture of the space shuttle). The SRB's are essentially long tubes of solid fuel, like a big firework. They're made of several smaller tubes clipped together by large joints, sort of like coke cans stacked together. To seal the joints and prevent hot gases escaping (which is bad) there are 2 rubber o-rings in each joint to produce a seal. \n\nThis is where the problem is: When it gets cold, rubber shrinks and gets weak, and this is what happened to the o-rings on Challenger. This had happened before on space shuttle launches: The shrunken o-rings had allowed hot gas to blast past them through the joint and got damaged, but had accidentally fixed themselves as they had been blown out of the notches they where seated in and sealed the joint.\n\nWhat happened on Challenger didn't go as well. The day of the launch and the night before had been very cold, and the o-rings had shrunk. When the solid rocket boosters ignited at lift-off, the hot gases rushed past the o-rings and eventually destroyed one set of them in the SRB on the right. Also, the high pressure inside the SRB caused the casing of the booster to balloon outwards (another design flaw). This combined to make a huge gap in the joint, through which a stream of very hot gas poured through. This hot gas stream began to burn through one of the joints holding the SRB to the big orange fuel tank. Eventually this joint between tank and booster failed completely: the top of the solid rocket booster detached and smashed through the orange tank, smashing it apart. This caused the contents of the tank (liquid oxygen and hydrogen) to ignite causing a huge explosion which tore apart Challenger. "
]
}
|
[] |
[] |
[
[]
] |
||
pyqd3
|
how is it that an equation is able to describe the nature of reality?
|
While I was watching a video it said, "Einstein's equation suggested the universe was either expanding or condensing." How can abstract numbers define something like the nature of the universe?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/pyqd3/eli5_how_is_it_that_an_equation_is_able_to/
|
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"text": [
"Equations aren't about numbers. You put numbers into them and get numbers out of them, but that's not the point. The point of equations is to express *concepts*, by describing how different numbers are related. \n\nSo with the right equation, you can describe how the expansion of the universe is related to certain numbers. If you find that the expansion rate number is not 0, then the universe is either expanding or contracting.",
"You're sort of mistaking cause and effect. The equation (or theory) is built to describe observations that have been made. Once you have a theory that does a good job of describing what you've observed, you can then use the theory to *predict* things.",
"How did we get the idea for numbers?\n\nWe got it by looking at the world around us and noticing that sometimes things happened in pairs, or in threes, or fours, or so on. You have *two* eyes and *one* nose; you have *ten* fingers. If you hold up your hands in front of your face, you'll notice that you have *the same* number of hands that you have eyes. Hands and eyes are not the same, but \"two\" describes both your hands *and* your eyes.\n\nThen we noticed that if you have two apples and someone gives you three apples, you now have five apples; and then if you eat one, you have four left. And it works *the same* for carrots, or cows, or dollars as it works for apples. The same equations 2 + 3 = 5 and 5 – 1 = 4 could describe what happens when you give and take chairs, or figs, or houses. Adding and subtracting work the same for numbers no matter what the numbers are counting.\n\nYou mentioned that numbers are abstract. But what does \"abstract\" mean? It means *exactly* that numbers work the same regardless of what they are numbers of. \n\nThe same is true for other math ideas, like triangles. If you have a triangle whose sides are all the same length, then its angles will also be the same. This is true no matter if the triangle is drawn on a piece of paper or built out of popsicle sticks. Triangles are abstract: the rules for triangles work the same no matter what the triangles are made out of.\n\nScientists keep finding things in nature that math describes well. For instance, there is a math pattern called the Fibonacci numbers, that goes like this: 1, 1, 2, 3, 5, 8, 13, 21, and so on. Each Fibonacci number is made by adding the two previous ones. Fibonacci numbers were invented by a guy whose nickname was Fibonacci (big surprise!) but he invented them for a pretend puzzle.\n\nThen later it turned out that [they are in flowers](_URL_0_), and other things in nature, for reasons that have to do with how the flowers grow. Fibonacci didn't invent them to describe flowers, but when someone went and looked at flowers, they found Fibonacci numbers there ... and they figured out why, too ... because the *abstraction* of Fibonacci numbers shares the same pattern as how the flowers grow.\n\nThe same sort of thing keeps happening. People who look at various things in nature find out that they follow patterns, and that these patterns can be described with math abstractions. In fact, you could say that math is all about *what abstractions are possible* — coming up with new ones and finding out what patterns they produce — while science is (in part) about looking at the world and finding out if there are abstractions that fit the world's patterns.",
"How is it that I can figure out how much money I have at the end of the month when I know my starting balance, income and expense?\n\nHow did these \"abstract numbers\" describe my current financial situation? This is _such a difficult concept_."
]
}
|
[] |
[] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Fibonacci_numbers#In_nature"
],
[]
] |
|
5fpk23
|
Is mild psoriasis associated with a shorter life expectancy?
|
While looking for information on psoriasis, I came across two studies that seem to completely contradict each other. In [this study](_URL_1_), mild psoriasis is not associated with an increased risk of death. However, in [this study](_URL_0_), people diagnosed with even mild psoriasis before the age of 25 die, on average, 20 years before the general population. That's an incredible difference! Which study is more likely to be accurate?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5fpk23/is_mild_psoriasis_associated_with_a_shorter_life/
|
{
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"danxl7e",
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],
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2,
2
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"text": [
"For Gulliver et. al, it looks like they focused on hospitalized patients. For Gelfand et. al, they mention that they found that patients treated as outpatients fair better. Perhaps the patients who were hospitalized had other manifestations of the disease and thus were more likely to have complications, which could have affected the mortality rate in that particular study. ",
"I wasn't able to access that second article because it is behind a paywall, so it is hard to determine how reliable it might be. However, the first study, which showed no effect seems quite strong. It involves a very large number of patients with mild psoriasis (133,568) and over half a million control non-affected people. Studies with such a large number of subjects tend to be more reliable. The other study, which considers only people of New Foundland or Labrador descent likely involves fewer subjects and likely might be less reliable."
]
}
|
[] |
[
"https://www.ncbi.nlm.nih.gov/pubmed/21291654",
"https://www.ncbi.nlm.nih.gov/pubmed/18086997"
] |
[
[],
[]
] |
|
2zu53h
|
why do you see more in the camera app, depending on the orientation of your phone?
|
My friends were freaking out about this today. Why when you rotate your phone while taking a picture, doe do you see more depending on your phone's orientation?
Like, in portrait you see more up & down, and in landscape you see more left to right.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2zu53h/eli5_why_do_you_see_more_in_the_camera_app/
|
{
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"cpmaf8q",
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],
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5,
2
],
"text": [
"Your scene is a rectangle not s square so the camera is cropped to fit the display. ",
"A smartphone's camera is 4:3 in landscape, so when you take a portrait shot it's 3:4. Almost all camera sensors are rectangular, DSLR's and high-end compacts that shoot RAW are 3:2 in landscape."
]
}
|
[] |
[] |
[
[],
[]
] |
|
42cugu
|
does alcohol increase or decrease dopamine levels
|
I know at first alcohol raises dopamine levels but what about in the long run?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/42cugu/eli5does_alcohol_increase_or_decrease_dopamine/
|
{
"a_id": [
"cz9bxje"
],
"score": [
2
],
"text": [
"[Read this](_URL_0_)\n\nI am the walking hedonic dysregulation theory"
]
}
|
[] |
[] |
[
[
"http://www.hamsnetwork.org/dopamine.pdf"
]
] |
|
2r1nch
|
why are republicans against giving the lgbt community equality?
|
I read an article about Democrats wanting to introduce a bill in Congress that would ban discrimination and the like targeted at the LGBT community. For what reasons would conservatives not be in support of this?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2r1nch/eli5_why_are_republicans_against_giving_the_lgbt/
|
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"text": [
"IMO, it's got not much to do with human's rights then it has to do with the religious wing. \n\nIf I'm not mistaken, many of the active conservative communities oppose to the LGBT and hence their support or lack of support may become a problem for their vote bank, which is made up of conservative community.\n\nThese are my opinion, please feel free to correct me if I'm wrong.",
"From a political perspective, a large voting block for the Republican party are older and very religiously conservative (Usually Christian, specifically protestant). The more conservative forms of Christianity do not favor homosexuality. If the Republican party were to openly support protections for homosexuals (and others that fall into LGBT categories) they risk alienating an important voter block, which affects their reelection chances and political power.",
"A lot of Republican voters are conservative Christians who believe that homosexuality is a sin. A Republican politician who supports the LGBT community risks losing their votes.\n\nI think that one thing that might help you understand it a little better, from that perspective, being gay isn't just an acceptable difference in someone's personality, it's something that's wrong with them, or that they're doing wrong. They believe that creating laws that cater to LGBTs encourages it, and causes some sort of national moral decline.",
"Cause the government spends all of it's energy pretending to be useful and milking whatever funding they possibly can for it's maximum personal profit. They have shown by opting out of anything they force on us that they are not interested in us in the slightest. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
21m9rd
|
How do cats see in the dark?
|
And specifically, how were they able to evolve that way when humans could not? In the second episode of the new Cosmos series with Neil DeGrasse Tyson, he spends time talking about how the eyeball was originally evolved in an underwater environment by a common ancestor of ALL living creatures today, including humans, and when creatures evolved into land-based mammals they were at a disadvantage because their eyes could not see as well on land as fish could underwater. That is why, even today, humans cannot see and discern fine details in the dark as well as fish can in the ocean. But I've also read that cats have AMAZING night time vision and can see perfectly well in low-light environments.
So my question is, how do they do it, and why did they evolve that way and humans did not?
|
askscience
|
http://www.reddit.com/r/askscience/comments/21m9rd/how_do_cats_see_in_the_dark/
|
{
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"text": [
"Great question! Firstly, a quick description of vision (the how): \n\nSpecialized neurons called photoreceptors are what pick up light and convert it into signals that the brain can interpret. The two major types of photoreceptor cells are rods and cones (you may have heard of these before). Cones function best in bright light and are responsible for colour vision and vividness of colour. Cones are packed in an area near the middle of the retina. \n\nRods function less in higher light and these cells are concentrated around the periphery of the retina, thus aiding in peripheral vision and in low light vision simultaneously. Their sensitivity makes them almost entirely responsible for night vision.\n\nAs you can probably tell, humans have more cones than rods and cats have more rods than cones. This evolved due to different selective pressures facing felines and primates. \n\nFelines are typically hunters that don't need to discern too much colour in the environment, because they require more acuity of movement to track prey, and night vision for night hunting. \n\nPrimates are herbivorous or omnivorous, and for primates it is advantageous to discern reds and oranges associated with fruit. Also as humans became bipedal they became taller and better acuity of detail made it possible to see far away both on Earth to see dangers/resources and into the sky, enabling better pattern recognition (to tie it back to Cosmos). "
]
}
|
[] |
[] |
[
[]
] |
|
35j39o
|
why do people use itunes even though there are may other ways to download music.
|
^
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/35j39o/eli5_why_do_people_use_itunes_even_though_there/
|
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"text": [
"I believe you have to use iTunes to download to apple devices, and if you want to legally purchase music why not use iTunes as opposed to any other format",
"The Itunes store was one of the first big services for purchasing music legally on a computer. It is also has a huge amount of content in not just music, but also in movies, books, podcasts etc. \n\nMany people started using itunes back when there weren't that many competitors and they continue using it today because they are either pretty pleased with it or because they've already spend enough money on their itunes account that they don't feel much of a push to switch. Most of us really don't want six different accounts with six different services with a few purchased songs on each account. We'd much rather just have everything in one place.",
"Because it's widespread, easy, and is how you load music onto the most popular music players in the world.",
"Because it is a convenient place to purchase music. Same thing as Google Play Music or Amazon Music. Of course the software itself is required to sync Apple products, but that's sort of unrelated. I don't own any Apple devices but I still use iTunes to purchase my music over Google Play."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
120tsa
|
Are the Voyager probes still taking pictures?
|
I know the Voyager probes are sending data, but are there any pictures of the possible heliosphere or the other outer reaches of the solar system contained in that data?
|
askscience
|
http://www.reddit.com/r/askscience/comments/120tsa/are_the_voyager_probes_still_taking_pictures/
|
{
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3
],
"text": [
"The cameras on the voyager probes have been disabled to save power.",
"In the [wikipedia article](_URL_1_) in the \"Scientific instruments\" yoi can see the current status.\n\nIt surprises me that in my research I found this [article] (_URL_0_) as I thought the cam was disabled a while ago.\n\nAnyways, now it seems that the cameras are disabled anyways.",
"According to [this page](_URL_0_), most scan-platform stuff was shut down to save power in the '90s. Heaters for these instruments were also turned off, I'm uncertain if this means they will never operate again. The plutonium fuel decays at about 4.2 watts/year. Some instruments will be working beyond 2020, however my knowledge of JPL acronyms is a bit spotty. Cool article though, and a reminder of just how primitive the computers on these probes are (but oh so durable!) \n\nedit: Wikipedia references the JPL pages but paraphrases:\n\n*2020 [Voyager 1]: Start shutdown of science instruments (as of October 18, 2010 the order is undecided but the Low-Energy Charged Particles, Cosmic Ray Subsystem, Magnetometer, and Plasma Wave Subsystem instruments are expected to still be operating)*",
"the cameras wouldn't be able to see anything even if they were on. \n\nit is really really Dark out that far from the sun. \n\n\n",
"Out of curiosity, how long will the New Horizons probe (currently en route for a 2015 flyby of Pluto) take to reach the same distance from the sun as the Voyager probes?"
]
}
|
[] |
[] |
[
[],
[
"http://www.dailymail.co.uk/sciencetech/article-2196997/Voyager-1-beams-images-Earth-tiny-dot-prepares-interstellar-space.html",
"http://en.wikipedia.org/wiki/Voyager_program#Scientific_instruments"
],
[
"http://voyager.jpl.nasa.gov/science/thirty.html"
],
[],
[]
] |
|
4u6i7z
|
does ice go bad? if i found some ice cubes that had been sitting in a freezer since 1945, could i eat them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4u6i7z/eli5_does_ice_go_bad_if_i_found_some_ice_cubes/
|
{
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"text": [
"If the ice was made from good water in the first place it is probably good. Glacier ice is sold as a novelty. It is thousands of years old.\n\nIce made from contaminated water is not good and probably stays contaminated for a long time.\n\nIce and soap which falls on the ground can be rinsed off. It is then clean. The surface melted.",
"Assuming the ice hasn't subliminated(you might need a bigger ice block) and was placed in sterile and cold enough conditions. Yes you could eat it."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1jw5mt
|
3d movies
|
As the title states. I'm wondering how 3D movies work, and how they actually become 3D. Thanks (:
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jw5mt/eli5_3d_movies/
|
{
"a_id": [
"cbiv55u"
],
"score": [
3
],
"text": [
"To keep it simple. You can produce 3D in your vision every day because you have two eyes.\n\n3D movies are filmed with two camera lenses, side by side, similar to your eyes. \n\nWhen shown on your TV/movie theatre, the special glasses you wear makes it so the picture captured from the left lens is only transmitted to your left eye. Same goes for the right. "
]
}
|
[] |
[] |
[
[]
] |
|
sqi7j
|
Can r/askscience please tear this apart? I don't want it to be true.
|
askscience
|
http://www.reddit.com/r/askscience/comments/sqi7j/can_raskscience_please_tear_this_apart_i_dont/
|
{
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"text": [
"Same thing was posted a few days ago. It was bollocks then and it's bollocks now. A specialised nuclear warhead or 50 couldn't wipe out 3 billion people, let alone a piddly power station fuel rod.",
"I tend to not trust websites when the frontpage has topics including an unhealthy combination of the following: failing america, middle east nukes, CIA, \"Obama regimes,\" and \"super secret\" hypersonic aircraft.\n\nI would say it is a conspiracy theorist site."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3otc00
|
how did america's economy overtake britain in the late 1800s?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3otc00/eli5_how_did_americas_economy_overtake_britain_in/
|
{
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"text": [
"America had a ton of natural resources, long period of peace to develop, rapid increase in production due to industrialization, and rapid increase in work force due to immigration. Factor this in with increasing education and the growth of cities, and you get a massive us manufacturing and agriculture sector that great Britain did not have neither the raw materials nor the manpower to compete with"
]
}
|
[] |
[] |
[
[]
] |
||
5t2ufm
|
What does the Schrodinger equation mean and what does it tell us?
|
I am beginning quantum mechanics and we have been studying the Schrodinger equation pretty extensively. But I am confused about what this equation represents and why can't we derive it?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5t2ufm/what_does_the_schrodinger_equation_mean_and_what/
|
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"text": [
"The time-dependent Schrodinger equation tells you how a quantum state vector evolves with time. It says that the Hamiltonian operator is the generator of translations in time. If you know the state vector at time t = 0, the Schrodinger equation and the Hamiltonian tell you what the state vector will be for all time.\n\nYou can't derive the Schrodinger equation because it's a **postulate** of quantum mechanics. You can either postulate linear and unitary time evolution, and the TDSE follows, or you can just postulate the TDSE directly. Either way you're making an assumption about how quantum states evolve with time. This is a fundamental assumption to quantum mechanics, hence why you can't \"derive\" it.",
"You can produce the Schroedinger equation - out of a hat - by several plausible routes, depending on what you allow in your starting point. But none of this constitutes a derivation, nor is any other equation in physics derived from first principles.\n\nThe usual approach at universities is to take the line that seems to be easiest for students to handle. As an undergraduate, you need to recognize that you are only being fed a small portion of what has been discovered in your subject area. ",
"Also it is important to know you just can't derive all fundamental laws of nature from first principles. Some things have to be observed in nature and then guessed to be correct. Like for example, you can't derive newton's law of gravitation but it encapsulates a hypothesis about how that system evolves. Schrodiger's equation is the same.",
"Schrödinger's equation is the deBroglie matter-wave-equivalence hypothesis taken seriously.\n\nFourier theory tells you that you can write waves in terms of complex exponentials, i.e. exp(-i*2*pi*f*t) is a wave with frequency f.\n\ndeBroglie tells you that a particle whose corresponding oscillates at f has energy E = h*f.\n\nNow, Schrödinger wants to build a linear differential equation that describes matter-wave dynamics. So how do you get deBroglie's energy from a wavefunction?\n\nEasy: d/dt exp(-i*2*pi*f*t) = -i*2*pi*f * exp(-i*2*pi*f*t). So you've extracted the frequency f from the function. Now just add appropriate prefactors, and you get Schrödinger's energy operator.\n\nThen you say \"total energy = kinetic + potential energy\", play the same game to obtain a momentum operator, and write kinetic and potential energy in terms of momentum and position.\n\nAnd out comes Schrödinger's equation.\n\n(Note that this isn't a rigorous definition, but it's what the equation means to me intuitively.)"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1u40tg
|
why does the hair of humans get oily after a day or 2 without bathing, but a cat's hair always feels so soft after not being for 11 months or more?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1u40tg/eli5_why_does_the_hair_of_humans_get_oily_after_a/
|
{
"a_id": [
"ceeamxa"
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"text": [
"Your body overproduces skin oil because you wash it away every day. If you go a month or so without using soap or shampoo, your body will eventually reach an equilibrium, and it'll be a lot less oily and gross than you think.\n\nCats also spend a lot of time grooming their fur."
]
}
|
[] |
[] |
[
[]
] |
||
z0lsd
|
How physically fit were soldiers of antiquity? What was their training like? For that matter, how fit were average people?
|
Spartacus and 300 have deluded my perceptions.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/z0lsd/how_physically_fit_were_soldiers_of_antiquity/
|
{
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"c60g57s",
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"text": [
"You could always go to the source itself. Ad fontes.\n\nThis is *De Re Militari*, an elementary military training manual from the late Roman Empire. Check out the recommendations for the skills that recruits should posses and the exercises they should be trained in; I always thought that they were fairly simplistic, and written from the point of view of a commander who had ended up with raw recruits who couldn't swim, had no knowledge of weapons, etc.\n\n_URL_0_\n\nspecifics on physical training:\n\n_URL_0_dere03.php#03\n\nI have never seen these sources as describing particularly outlandish physical specimens. They were most likely young, healthy men in the prime of their lives, but not superheroes. Put \"300\" out of your head.\n\nWikipedia on Vegetius:\n\n_URL_0_\n",
"Prenatal care and nutrition have improved dramatically. That means a modern 18-year-old recruit, on average, is going to be taller, with a higher IQ and better reflexes. A never-ending flow of proteins and fat in infancy, as well as a cornucopia of antibiotics and vaccines, provides lasting advantages. \n\nThe ancients have their advantage, too: Endurance. Ancients have callused feet from a lifetime of walking. They can run for hours because their feet have been shaped and toned in the manner human feet are designed for. Ancients have never known a padded chair, so they squat using back and leg muscles that are tightened and trained in a manner only modern Olympians approach. They shrug off pain that would leave moderns flinching and crying. \n\nMost important: ancients have been exposed to death in a way moderns have not. They have seen all the animals that go into their meat stew die. One of their first childhood jobs was ripping the feathers off a chicken their mother just decapitated. They watched their little sister die, covered in pustules. They beat dogs to death for fun as a child. Their first kill wasn't watching a puff of red mist through a scope. They tasted their enemy's sweat, smelled his fear; his open neck sprayed blood on their face. The ancients have stabbed and ripped. They have laughed at a dying man. They've raped screaming women, kicked dying children apart. \n\nIf you take a modern army and an ancient army, the ancients will be torn to bloody shreds. They'll lose strategically, they'll lose tactically. But in smaller groups - up close, at knife's edge - the ancients have a taste for blood and madness that will shock the moderns. ",
"I can only speak to mediaeval and renaissance times.\n\nTraining included, but was not limited to: squats, lunges, and dead lifts with a very heavy stone, throwing of moderately heavy stones, running, tumbling, javelin throwing, tug of war, sick wrestling (this is bitch!), and pommel horse. Then, of course, hand to hand combat (grappling), dagger combat, and sword training. I assume everyone in the mediaeval era also worked with spears.\n \nThis was, of course, for the upper tiers of society, who wound up with a strong and slender physique by training for war and judicial combat. Folks with the large mass we associate with weight lifters would be said to be built like a peasant (many would develop brute strength form a lifetime of labor).\n\nI would say that the difference in diet from then to now is a mixed bag, but I'm no nutritionist."
]
}
|
[] |
[] |
[
[
"http://www.pvv.ntnu.no/~madsb/home/war/vegetius/",
"http://www.pvv.ntnu.no/~madsb/home/war/vegetius/dere03.php#03"
],
[],
[]
] |
|
4jwmwz
|
why does red on a blue background or vice versa hurt our eyes?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4jwmwz/eli5_why_does_red_on_a_blue_background_or_vice/
|
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"it hurts ours eyes? ",
"Certain high contrasting colors are difficult to focus on. It doesn't physically hurt our eyes, it's your eyes straining themselves to actually focus.\n\nOne that always gets me is the Walmart sign at night. I know what it says, but it's hard for me to focus and read it without staring at it. The big blue letters are hard for me to read at night. \n\nIf I do stare, it will begin to make my eyes hurt because I'm straining myself to make them focus. I also have astigmatism, which makes focusing on anything more difficult. ",
"Your eye's lens has a small amount of chromatic aberration, which is an optical term that means that different colored light is focused slightly in front of or behind the eye's retina. When looking at one of the two, your eye just slightly adjusts the focus forward or backward to focus the image, but in the case of red on blue, the discomfort is caused by the eye not being able to get both colors in focus no matter which adjustment is chosen. "
]
}
|
[] |
[] |
[
[],
[],
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] |
||
2wnuc4
|
Black History Month AMA Panel
|
February is Black History Month in the United States, created in 1976 to recognize the important, and far too often ignored, role that African-Americans have played in the country since its colonial beginnings. In recognition of this celebration, we've assembled a fantastic panel for you today of experts in the field, who are happy to answer your questions pertaining to these vital contributions.
So without further ado, our panel includes:
* /u/Shartastic [African American Sports | Baseball and Horse Racing](#flair-northamerica) studies African-American athletes from the 19th Century into the early 20th Century. His focus is on African-American jockeys and the modernization of sport, but he's happy to talk about other sports too.
* /u/sowser [Slavery in the U.S. and British Caribbean](#flair-northamerica) specializes in the comparative history of unfree labour, with an emphasis on the social and economic experiences of the victims of racially-based systems of coercive or forced labour. His focus here is the experience of slavery in the United States (and its precursor colonies) and the British Caribbean, from its inception in the 16th century to abolition and its aftermath in the 19th.
* /u/dubstripsquads [American Christianity](#flair-other) is working on his MA in African-American studies with a focus on desegregation across the South. In addition he has an interest in the role of the church (white and black) during the Civil Rights Movement, and he happy to answer anything on Georgia and South Carolina's Civil Rights and anti-Civil Rights movements as well as anything on the Black Church in general.
* /u/LordhussyPants [Racial History | New Zealand](#flair-northamerica)is headed into postgraduate studies where he'll be looking at the role education and grassroots organizing played in the Civil Rights movement. He's also also studied wider American history, ranging from the early days of the colonies and the emergence of racism, to the 70s and the Black Power movement.
* /u/falafel1066 [Pre-Civil Rights Era African American Radicalism](#flair-northamerica) is in her last year of a PhD program in American Studies, working on her dissertation titled "A Bible in One Hand, a Brick in the Other: African American Working Women and Midwestern Black Radicalism During the Depression, 1929-1935." She specializes in Black radicalism, but can answer most questions on 20th Century African American history through the Black Power movement. She also studies labor history and American Communism as it relates to African American workers.
* /u/FatherAzerun [Colonial & Revolutionary America | American Slavery](#flair-northamerica) is a Professor of History at a 2 year college and History Advisor. His specialties are in colonial history and slavery / the Antebellum South. While he can talk about some areas of the Antebellum period, he is focused on late colonial and Revolutionary slavery.
* /u/origamitiger [Jazz](#flair-northamerica)
Please do keep in mind that our panel comes from a number of timezones, with differing times that they can be around, so while I can assure you they will do their best to get to everyone's question, I do ask that you have a little patience if an answer isn't immediately forthcoming!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2wnuc4/black_history_month_ama_panel/
|
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"During my readings on the Civil War, and the US Colored Troops, a rather brief aside I once encountered referenced the failure of the Freedman’s Savings Bank, and how its crash wiped out the savings of nearly 2/3 of all African-American veterans. It was only mentioned in passing though, so I was hoping one of you might be able to provide some more background on the Bank, and why it folded. ",
"Hi guys, thanks for doing this!\n\nI have two questions, focusing on the 20th century, so mostly for /u/LordhussyPants and /u/falafel1066\n\nWhat was the effect of the drug trade on the black community during the ‘60s and ‘70s?\n\nThe second question:\n\nThere seem to be differing ideas about the legacy of the Black Panther Party, from being criminals who inspired the increase in murders the next decades to being revolutionary dreamers who resisted the police. I was wondering what you thought the primary legacy of the Black Panther Party was.\n",
"I have a question for /u/dubstripquads. Can you explain how religion in black churches served to either motivate the Civil Rights Movement or to pacify its participants? ",
"From what I understand, in modern times, a lot of the conservative/liberal divide can be better accounted to rural/urban rather than South/North. In other words, there are rural areas in the North that are more conservative and urban areas in the South that are more liberal.\n\nMy question is was this also true during the time of Civil Rights? In other words, were there rural areas in the North that were more pro-segregation than urban areas in the South? And as a follow up to that, what were the main factors that led a place to be more or less welcoming for African Americans?",
"I asked this before and unfortunately it went by unnoticed, but this might be a good place to try again!\n\nIn Isaac's Storm, the author noted that in the late 1800s Galveston, Texas had an abnormally strong and vibrant African-American community, and how they essentially controlled the docks due to their unionized workers. But it is really just in passing, so:\n\n* Firstly, how true is this? And then, how did this come about?\n\n* What was life like for a freeman pre-Civil War?\n\n* Was this status able to survive the destruction of the city in 1900?",
"This is a question for whomever is interested, likely /u/FatherAzerun.\n\nI've heard about maroon communities in South America and the Caribbean, but relatively little about these societies in North America. Could you describe some of the maroon communities in the United States? When did they form? How long did they persist? Can you comment on the connection between maroon communities and the Seminole Confederacy in Florida?\n\nThanks!",
"I'm curious about the effect the Nation of Islam had on the civil rights dialogues. Do you feel that the Nation of Islam ultimately helped or hurt the cause of civil rights? What effect did its rhetoric of racial separation have on the civil rights debate?",
"To what degree did African American musical traditions vary from place to place before radio?\n\nIn ~1910, did Black people in Texas have different styles from Black people in Virginia?",
"Did traditional West African or even Muslim traditions influence 18th and 19th century African American Christianity?",
"Another question, but for /u/shartastic - I admit, I know nothing about African-American jockeys. Who do you think are some of the greatest African-American jockeys? When I see races like the Kentucky Derby on television, it looks like there are no African-American jockeys. Has there been a downturn in African-American participation in racing? Why or why not?",
"It's well known that second wave feminism comes up around the time of the Civil Rights Era (in the 60s and 70s). It's also been criticized as being primarily a white, middle-class woman's movement (which leads to new waves and new concepts and other within-the-twenty-year-rule stuff that I can't talk about).\n\nI'm curious as to see whether second wave feminism played a part in the civil rights and black freedom movement, and whether it became a dividing force between black men and women activists and between black women activists. I'm aware that it did lead to a divide in the Chican@ movement; did something similar occur in the fight for black rights (for lack of a better term)?",
"I also have a bit of a silly question for /u/FatherAzerun - When I was in high school, I was given an assignment to write about the effect slavery had on the outbreak of the American Revolution. It was a question I struggled with at the time, and am still a bit unsure about. So, might I ask, just to set my own ideas straight - what effect did slavery have on the outbreak of the American Revolution? How much of a cause was it, if at all?",
"To my understanding it is still more of a stigma to be homosexual within the black community than in general in the US. Is there any historical reasons for this? ",
"My question could be applied to modern times as much as historical, but this is Ask Historians of course and has the 20 year rule, so please just interpret my question as referring purely to the historical situation up till 1995 and let's ignore what may or may not have changed since:\n\nThat said, this is something that I'd really like to learn some more about. As a European, I have a very distant perspective on American racial matters. And I'll come clean, up till recently I had gained the pretty simplistic impression that post-civil rights era, the remaining issue were entirely about African-Americans having as a result of their history a situation of being disproportionally poor and being culturally mismatched with the wealthier European-Americans.\n\nIf the above is unclear I apologise for lacking the skill to explain what I thought succinctly, but it doesn't matter. Because the point is that I've recently read some of the writing of [Ta-Nehisi Coates](_URL_0_), as well as some other writings of similar persuasion, and he directly skewered all those positions I had.\n\nThe impression I've gotten now is that the real issue for African-Americans post-slavery has been being lower class compounded by systemic racism denying African-Americans the (already limited) social mobility to get out from being lower class. To get out of vagueries and into practical examples: Coates writes for example about how lynchings were sometimes portrayed as a kind of cultural conflict, but in actually often targeted those African-Americans who had begun to accumulate wealth and thus needed to be kept down.\n\nMy actual question is: to what extent is the above class-racism narrative accepted in historical circles? Are there studies that have looked into the historical social mobility of African-Americans vis-a-vis other groups? Are there competing alternative narratives? Is Ta-Nehisi Coates seen as completely nuts or poignantly accurate?\n\nI'd be very grateful for any response to would help educate a non-American like me on the way the real experts are looking at these issues (in an historical context).",
"to /u/falafel1066: love the title of your dissertation. can you tell me which groups you examine? I'm especially interested if you've done research into any of the takahashi-connected groups like the \"peace movement of ethiopia\".",
"to /u/LordhussyPants or whoever else wants to chime in: How important were veterans in serving as organizers and leaders in the early civil rights movement? Also, what about trends in organizations that many leaders and early members were in before they joined up with the CRM",
"What has made African Evangelical churches different from white protestant or catholic churches? Where do the call and response and unique sermon style originate from?",
"/u/FatherAzerun, /u/sowser, or anyone--do you know of new (since 2010) research on US Muslim slaves?",
"Can somebody discuss how the African American participation in WWII changed things in the post war years? ",
"What impact did African American service in World War One have on the emergence of civil rights movements or on race relations generally? ",
"Was there ever any serious discussion during the periods of Western Expansion (Antebellum or post)to create, a territory or colony, what have you, primarily for blacks? Similar to Liberia, but with in the jurisdiction of the USA? If so, how far did these discussions go? ",
"I'm not sure if this is something that's within the expertise of any of the panel members, so apologies if this lies outside your scope.\n\nOne of the things that stands out in African-American history to me has always been the Tuskegee Airmen. Though they're some of the most famous pilots of the second world war (or at least, one of the most famous groups of pilots, if not necessarily individually remembered by the public), I'm not aware of any of the pilots from the airmen going on to do what so many other pilots did post-war: that is, go on to become test pilots, like say Chuck Yeagar. Was there any kind of movement amongst African-American pilots to get into test pilot programs (and similarly, what was any backlash like?)? Also, the first African-American astronauts as far as I know only come around in the late 1970s, so what was the relationship like between NASA and any African-Americans who did try to get in to the programs?",
"how many major attempts by africans were made to repatriate the diaspora? ",
"* Lynchings are often portrays as a systemic way of maintaining racial oppression, and undoubtedly they were. However, I'm curious to what extent this was intentional and perceived at the time. Or put it in other words, would people carrying out lynchings have thought that their actions were targeted at the greater black community, or did they only think they were targeting individuals, and the collective aspect is only apparent at a remove?\n\n* Atlanta has the moniker \"the city too busy to hate.\" Where did this come from, and to what extent was it justified?",
"In a book I recently read about propaganda posters from the Cultural Revolution, it was mentioned that many people in the black freedom movement looked up to the ideals depicted. To quote:\n\n > [T]here was significant political exchange between the Chinese communist government and African Americans in the United States.\n\n > \\- \"Revolutionary Chinese Posters and their Impact Abroad\", *Chinese Posters: Art from the Great Proletarian Cultural Revolution*, Lincoln Cushing and Ann Tompkins.\n\nSpecifically, the passage was talking about how the Black Panther Party looked up to socialist countries, such as China and Cuba, in the belief that their struggle was sort of global struggle.\n\nHow connected was the Black Panther Party with Marxist ideology? Did Marxism and communism have influence over the wider black freedom movement?",
"I have questions about the NOI also, or more specifically about islam during the CRM. Were there african americans converting to islam outside the NOI or was it very specifically in that movement? After the 60s did islam stay important in the african american community? Or was it ever important? Was there a connection between the NOI and muslim countries, did the NOI receive financial or other help from these countries?\n\nMy other interest would be how much influence the soviet union had in the NOI or any other group during the CRM? Did they receive help in any form, were they influenced without knowing it? Did the FBI or any other agencies attack african american leaders based on false or real claims of helping the soviet union?\n\nEdit: Another one: Generally how much role did the CRM played in the cold war?",
"Fascinating AMA. Promoted by the decline of African-American jockeys, and the post Reconstruction reaction against civil rights for non whites in general, I'd like to ask if\nthere was a similar loss of standing for African-Americabs in white collar and/or skilled worker occupations during this time period? In other words, were there more black lawyers, doctors, cigar makers, circa 1880 than circa 1830? Did professional organizations become more segregationist over time? Were some of the arguments behind occupations becoming more regulated (requiring law school for instance) overtly racial in their appeal?",
"Oh man I hope someone can answer my Marcus Garvey questions. I have about a million!\n\n\nWhy did Du Bois hate Marcus Garvey so much? Du Bois had rivalries but this one seemed pretty ugly.\n\nWas there a specific personal element or the strong differences between Marxism/Capitalism and \nBack-to-Africa/Integration?\n\n\n\n\nIs it accepted by historians that the Black Star Line was sabotaged by the FBI under Hoover or is there some ambiguity? In the books I've read it is either unmentioned or not expanded upon. \n\nAlso what was the Hoover's reasoning behind having such a strong opposition to the UNIA repatriation movement?"
]
}
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[
[],
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],
[],
[],
[],
[],
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[],
[],
[],
[],
[],
[],
[],
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|
6qgoc9
|
Why African rain forests are located on the western side and not all the way to Ethiopia and Somali?
|
What's the reason for Ethiopia being so arid? Shouldn't it get moisture from the Indian Ocean by the means of trade winds?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6qgoc9/why_african_rain_forests_are_located_on_the/
|
{
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"dky2ts8"
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"text": [
"My book shows the wet band going most of the way across the continent, to the headwaters of the Nile, but there is a dry spot on the far east, apparently with winds from the north east (Saudi Arabia) or SouthWest (Africa). Either way, they apparently do not pick up much moisture. "
]
}
|
[] |
[] |
[
[]
] |
|
rglu4
|
Is there any way to make oneself dream less often?
|
askscience
|
http://www.reddit.com/r/askscience/comments/rglu4/is_there_any_way_to_make_oneself_dream_less_often/
|
{
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"c45ng33",
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"text": [
"If you feel like you're dreaming too much, there is a good chance you aren't going into the deeper sleep cycles and there are factors preventing you from reaching deeper sleeping states. Generally either too much light in the bedroom or your health and hormones are out-of-wack.",
"Ever since I started smoking weed, I rarely have dreams. It seems to take a few days of sobriety for dreams to return.",
"You can learn to control them - that way you won't be able to get enough. The first evidence of lucid dreaming was produced in the late 1970s by British parapsychologist Keith Hearne. A volunteer named Alan Worsley used eye movements to signal the onset of lucidity, which were recorded by a polysomnograph machine.\n\nThe first peer-reviewed article was published by Stephen LaBerge at Stanford University, who had independently developed a similar technique as part of his doctoral dissertation. During the 1980s, further scientific evidence to confirm the existence of lucid dreaming was produced as lucid dreamers were able to demonstrate to researchers that they were consciously aware of being in a dream state, primarily using eye movement signals.\n\nI am working an app that records my eye movements during sleep and plays a song when it detects that I am dreaming. I can sometimes hear the songs in my dreams and act on that knowledge - by flying, for example. And I post the raw logs along with a printout of the most interesting minute to LSDBase every other day."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
31cc0e
|
why do autistic children frequently show extraordinary intellectual prowess?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/31cc0e/eli5_why_do_autistic_children_frequently_show/
|
{
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"text": [
"It's not all that frequent, it's just a persistent myth that autism is like \"Rain Man\". Probably because it makes us feel better about the situation.\n\nYou've got a relatively small number of people with low-level autistic children that a particularly bright or are autistic savants that are amazing at one thing.\n\nA much larger percentage are [more like this](_URL_0_).",
"They don't. Autism tends to interfere with people's ability to learn since most learning is social in nature. Most of the time when you see an autistic person with 'extraordinary intellectual prowess', what you're really just seeing is intellectual abilities everyone has focused on something most people don't care about - if you can name every person who has ever played Major League Baseball, it's impressive but not a sign of genius.\n\nYou also have to deal with the \"talking dog\" issue. When you see a dog that can talk, you're not impressed by its eloquence but by the fact that it can talk at all. Autistic people tend to make the same sort of impression that mentally handicapped people do due to their social difficulties. However, autistic people are not mentally handicapped - they have the same range of intelligence as everyone else. So when you see someone who can barely manage to hold a conversation but nonetheless can play a decent game of chess, you give them more credit than you would a non-autistic person who plays an equally decent game of chess."
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=w_23z9yJAq0&ab_channel=DiscoveryLife"
],
[]
] |
||
3zo1zk
|
why were flat roofs used so much in buildings in the past? did they not know the leaking problem it would eventually lead to?
|
I work in an old building that has a flat roof. It leaks every time we get a heavy rain. My boss has done almost everything and it eventually ends up leaking again. The school I went to had a flat roof and it leaked. Were they cheaper?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3zo1zk/eli5why_were_flat_roofs_used_so_much_in_buildings/
|
{
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"text": [
"Flat roofs are much cheaper to build than pitched roofs. They require less material and significantly less time. This is especially true when they are spanning a large open area like a gymnasium or warehouse.",
"We have flat roofs in Syria and they don't leak because all the water gets drained to the sides of the roof where you'll find pipes that take the water somewhere else. Flat roofs are amazing. I hate the roofs that are in 1st world countries.",
"Flat roofs aren't perfectly flat (level). They have a very slight pitch (angle) to them to shed water. Depending on design, this may be to one side, or it may be to multiple sides. Flat roofs are decked with a foam material, plywood, metal, fiberglass or some combination of these or other materials. The decking is then covered with a waterproof membrane such as EPDM, TPO or PVC. Think of stuff similar to a flexible koi pond liner, but the roofing membranes are usually two layers fused together with a skrim (think woven netting) in between the two layers for additional durability. Often, the membrane is then covered with a layer of loose gravel for additional UV and weather protection. The membranes are typically expected to have a lifespan of 15-30 years before requiring replacement, rated lifetime expectations primarily being dictated by the thickness of the membrane product used (typical measured in mils). These flat roofs are usually lighter, cheaper and faster to construct than truss style pitched roofs... Yet they offer about the same usable lifespan and function quite well when properly installed. Flat roofs also allow for much easier placement and maintenance of HVAC systems and venting systems on the roof. This becomes particularly important in high density commercial building areas where ground placement of HVAC systems may not be possible or financially practical due to limited ground being available (building occupies the entire lot), or when local zoning regulations have building height restrictions that necessitate them when someone wants to construct a multiple story building but remain under the height restriction. Pitched roofs create more unusable/non-occupied space/height.",
"Older building roofs had flatter roofs when the local weather threat was cold rather than rain. A flatter roof let snow piles up and insulate the home. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
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|
29ragi
|
why do grocery stores have paper bags for mushrooms and plastic bags for everything else?
|
Why do grocery stores have paper bags for mushrooms and plastic bags for everything else?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/29ragi/eli5_why_do_grocery_stores_have_paper_bags_for/
|
{
"a_id": [
"cinpv6x"
],
"score": [
2
],
"text": [
"Moisture. Moisture ruins mushrooms. Plastic bags hold the moisture in, while paper bags will absorb the moisture and keep the mushrooms looking fresh. "
]
}
|
[] |
[] |
[
[]
] |
|
rj8js
|
why doesn't reddit load image links in new tabs practically.
|
When i open a reddit link in a new tab, why does it open like this:
_URL_0_
instead of like this;
_URL_1_
possibly with some upvote and downvote buttons added in and a link to the original content in the toolbar that appears at the top.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/rj8js/why_doesnt_reddit_load_image_links_in_new_tabs/
|
{
"a_id": [
"c4697i5",
"c469wwz",
"c46a9s2"
],
"score": [
2,
2,
2
],
"text": [
"download reddit enhancement suite and you can set it to open images in a new tab",
"I believe most of reddit's users are not signed in. Opening a toolbar for every user would be impractical, because there is processing power involved each time that toolbar is rendered. Notice how it has points, comments, your username. \n\nIt is far cheaper to simply let the user go straight to the 'content' that has been linked to and provide users with the option to have a toolbar if and only if they sign up and log in. This ensures that a smaller percentage of the userbase is taxing the servers for this information on a regular basis which they can handle (mostly). ",
"If u use Chrome check 'hover zoom' :)"
]
}
|
[] |
[
"http://i.imgur.com/b90ZE.jpg",
"http://www.reddit.com/tb/iwkkx/"
] |
[
[],
[],
[]
] |
|
3610xe
|
how does the "communication" of evolution happen?
|
This mosquito had been buzzing around my ear for a few minutes. I acquired my target and brought him down.
My next thought:
"hmmm that's gunna suck when mosquitoes learn how to evade our hands."
The thing is, the mosquito is dead. He can't communicate any more, however evolution still happens. While mosquitoes might not be able to actually evolve an adaptation that allows them to predict our movements, it still brings up the question.
How does this "communication" of evolution happen?
Quoting [this study](_URL_0_) i found during my search for information"
"We discovered by the use of nonlinear techniques that states of interactional synchrony correlate with the emergence of an interbrain synchronizing network in the alpha-mu band between the right centroparietal regions. These regions have been suggested to play a pivotal role in social interaction."
Which I take as some kind of inter-brain communication.
So the existence of some kind of connection between living creatures is not out of the question.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3610xe/eli5_how_does_the_communication_of_evolution/
|
{
"a_id": [
"cr9pxw1",
"cr9pz43"
],
"score": [
7,
2
],
"text": [
"He dosent communicate. What happens is that you removed him from the gene pool, he can no longer reproduce. But all the mosquitos who didn't get hit can reproduce, so they can pass on whatever trait they have that allowed them to not get hit. So over time all the mosquitos that can get hit do and die, and all the mosquitos that have traits that allows them to not get hit pass on the ability to not get hit and it appears that mosquitos learned to evade getting hit.",
"Evolution did not necessarily happen.\n\nIn order for evolution to happen, a trait has to aid in survival in some way AND be passed down over generations and generations until it becomes common place because those without that trait didn't die.\n\nYou might have killed a mosquito with a really amazing genetic trait that was very beneficial... but it died. So perhaps you stopped a potentially beneficial trait from eventually propagating through the species.\n\nI am a little bit confused by what you mean by \"communication\". Mosquitos do not engage in meaningful social communication. The communication you refer to with the mosquito isn't so much about one mosquito letting another mosquito know somehow that, \"hey! If you juke left instead of right, you won't get hit by the hand!\" Rather, one mosquito is born with a genetic defect that makes it go left instead of right, which allows it to avoid hands better. It has avoided hands better so it lives and passes on its genes. The offspring get this same defect and they tend to live more than other mosquitos because of the defect and reproduce and have more offspring that also have the defect and also live, etc. etc.. Eventually in time it might make it so all mosquitos tend to be better at dodging hands.\n\nBut to give you an idea of how long \"in time\" might be... imagine having a specific trait... and then having a child that has that trait as well. Now imagine how long it would take for your family to eventually reproduce enough to replace all other families because in time your trait allows your family line to live and reproduce better than everybody else in the world. "
]
}
|
[] |
[
"http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0012166"
] |
[
[],
[]
] |
|
2y3jn4
|
Why do some historians regard the battle of seven pines as the most important battle of the civil war?
|
Why do some historians regard the battle of seven pines as the most important battle of the civil war?
All answers apreciated
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2y3jn4/why_do_some_historians_regard_the_battle_of_seven/
|
{
"a_id": [
"cp62lgb"
],
"score": [
2
],
"text": [
"The only one i've seen is that it places Robert E Lee in control of the Army of Northern Virginia since Johnson got injured during the battle. Why is Lee gaining control of the army of northern virginia important? Because he's Robert E Lee and the army of the Patomic goes from spitting distance away from Richmond to being pushed back to around the rhappahanock for most of the war (oversimplifying this part)"
]
}
|
[] |
[] |
[
[]
] |
|
3fgiuy
|
Wait, so were the Contras funded with Cocaine or Iranian arms sales?
|
I'm writing an essay on the Iran-Contra scandal, I've seen Kill The Messenger which deals with the CIA cocaine smuggling. But I've also been researching the Iranian weapons deals in exchange for hostages, which resulted income for the Contras as well. Was the U.S taking part in both? Can someone just lay it all out flat for me, how were the Contras funded during the 1980's?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3fgiuy/wait_so_were_the_contras_funded_with_cocaine_or/
|
{
"a_id": [
"ctohfb9"
],
"score": [
62
],
"text": [
"Yes, the US was taking part in both. \n\nThe Congress had cut off funding for the Contra war. The CIA and others, in the executive branch, were deeply committed to the war, but they now had no funding.\n\nThe US, as a part of the hostage release, began selling arms to Iran. We were officially allies, and supplying arms, to Iraq. The Iran Iraq war was going on at thus time. The Pentagon began funding the Contras with money from the arms sales. The money was transferred through third parties, essentially money laundering.\n\nTo me the entire scandal was a much bigger event than say, Watergate. For some reason, possibly because a President was forced to resign, Watergate will never be forgotten but Iran Contra has become just a minor footnote. Glad you're doing an essay on it.\n\n[Here](_URL_0_) is some great info on the topic."
]
}
|
[] |
[] |
[
[
"https://www.brown.edu/Research/Understanding_the_Iran_Contra_Affair/thehearings.php"
]
] |
|
6g5exu
|
what is the point of making medical students study all the subjects/all residential rotations?
|
If, for example, you know you want to be a psychiatrist, what's the point of having to go through the physical science rotations? Isn't that a waste of resources?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6g5exu/eli5_what_is_the_point_of_making_medical_students/
|
{
"a_id": [
"dinn14e",
"dinsnso",
"dinwxhm"
],
"score": [
5,
5,
2
],
"text": [
"Humans are one giant interconnected network of neural, chemical, and structural oddities. To understand the brain, you have to understand the body, and vice versa. It isn't a waste of time *at all*, and is quite necessary to have a holistic understanding of any one branch of medicine or psychology.",
"\nI like /u/police-ical answer a bit more than my own. \n\nYou need to have a basic understanding of how the body works and what can go wrong with it regardless of what field you go into. Without this knowledge, you can fuck up really badly. Let me give you a couplr examples regarding psychiatry.\n\nSay you have a patient coming into the hospital for a manic episode with psychosis and this patient is sent to the psych service for control. You may think he has bipolar disorder and typically you can give them haldol to control them but one of the things you need to do before giving haldol is the work up for hyperthyroidism. You need to be able to see the signs such as exopthalmos, tachycardia, pretibial myxedema, jitteriness and psychosis. If you miss this diagnosis you will be knocking out this patient over and over again without correction and could place the patient in danger of thyroid storm which could kill him.\n\nSay you have a patient with schizophrenia and you want to prescribe risperidone, an antipsychotic medication. You don't want to do this if the patient is complaining of vision problems or gynecomastia or galactorrhea because the patient may have a prolactinoma (a tumor) in his brain. \n\nIf you want to prescribe clozapine you need to be aware of the potentially deadly side effect of agranulocytosis which can disrupt a patients immune system. If a patient has certain immune problems then it may not be worth placing them on clozapine because you could cause fatal infections. But clozapine is also an amazing antipsychotic. This is a judgement call but you need familiarity with the various immune conditions a patient could have if you want to appropriately make this decision. \n\nI'm not even in the field of psychiatry but I know these things because if one of my patients were to come in on psychiatric meds or have psychiatric conditions, I'll need to take that into account with whatever I do. You could of course consult the hospital psychiatrist but you'll look like a fuckin retard (at least on these basic things). \n\nIt's true that a lot you learn in college and med school isn't applicable in practice but you also gotta realize that knowledge is foundational. You can't skip a layer of knowledge otherwise you'll have gaps and prob won't be able to critically think. And truthfully, there is a certain amount of studying strength you need to make it through med school and if you can't make it through the various science courses you most likely won't have the determination and skill to complete med school.\n\nAlso, from a practicality standpoint there are hundreds of fields you can go into through med school. It wouldn't be financially reasonable to split them all into different groups. You could of course go through different routes to enter certain fields: become a psychologist if you like psych, become a crna if you like anesthesia.\n",
"This touches on a lot of points I care about, and could merit an essay-length response, so to spare everyone I'll use bullet points:\n\n* It's not a rationally-designed system, so much as the one we have. Medical education in general is a little crappy and broken and outdated, and based more on tradition/convenience than preparing students to be modern doctors. Most people involved agree on this point, but no one's exactly sure what a better system would look like, and there are a lot of obstacles in the way of reform.\n* Everyone working in medicine benefits from some exposure to various parts, so they have an inkling of who to call when unfamiliar stuff shows up. You don't have to be able to handle every skin problem, but knowing a bit about rashes could make the difference between consulting dermatology, rheumatology, or infectious disease.\n* While many people go into medical school with some idea of what they want to do, many change their minds. It would be possible to tailor this somewhat, with the trade-off that people would have to commit to specialties a lot earlier, perhaps without getting as much exposure.\n* Psychiatrists certainly do need a good hunk of general medical training to be good at their jobs. Drugs do all kinds of weird things, psychiatric patients have other medical problems, and the line between \"psychiatric\" and \"non-psychiatric\" is quite tricky sometimes. Sadly, a lot of the medical training we do get isn't very relevant, which makes the stuff that IS relevant frequently get lost in the shuffle. It also tends to squeeze out valuable stuff like psychotherapy, which clinical psychologists get way more training in.\n\n**TL;DR: There's kind of a point. Not a great one.**"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
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