post_title
stringlengths 9
303
| post_text
stringlengths 0
37.5k
| comment_text
stringlengths 200
7.65k
| comment_score
int64 10
32.7k
| post_score
int64 15
83.1k
|
|---|---|---|---|---|
ELI5: What makes mirrors reflective? | For this, it’s important to understand what light is, an electric and magnetic field that changes in strength as it travels as a wave.
When it hits a conductor, like a metal, the electrons in the metal move freely, riding the wave up and down like a beach ball on the ocean. But when those electrons move, that motion causes another electromagnetic field to form. The one from the electron ends up canceling the one that is the light going forward, and you’re left with only the one from the electron going backward. Hence, reflection.
What’s weirder is that the electrons have a limit on how fast they can move, and if the light is too high a frequency, the electrons are getting pushed from both directions rather than riding the wave, so stay still. So they stop reflecting. The properties of the metal in question change their upper limit on how fast they can move, which causes certain metals to stop reflecting certain colors at different parts of the spectrum. Copper stops reflecting in the red, gold in the greenish-yellow, and silver or aluminum in the UV. This is why metals have different colors. | 12 | 17 |
|
ELI5: What specifically about puberty negatively impacts female gymnasts to the point that retirement occurs around age 20? | I've been thinking about this and am even starting to get skeptical of whether this is true or not. So I guess my question is divided into two parts: Is the retirement of female gymnasts after puberty for social or for established physical reasons? For instance, are elite female gymnasts forced to retire after their teens due to some wierd aesthetic reasons or is it due to some established medical reason such as: after __ post-pubescent age, the body becomes less compatible with gymnastics training demands? Post some real scientific studies if you can. | It is a few factors but the biggest two are strength to weight ratio and the change in size of the person.
When you train things like balance, one of the biggest components of gymnastics, you are training neuromuscular connections. When you grow, those change, performance dips. With girls their highest strength to weight + height ratio happens just before puberty, during puberty they have a lot of hip growth for instance, this will add weight but also change how they can balance. That change needs to be relearned.
All sports see this dip. Runners get slower at the start of puberty then get faster again, swimmers have a dip in performance... Pretty much any sport has this dip, gymnasts just experience it to a greater extent. The small stature of gymnasts also is good to maintain, easier to rotate a shorter person. | 20 | 17 |
Is every single living cell adjacent to or “have access to” a capillary? Are there living cells not next to a blood/O2 source, and if so, how do they survive? | Diffusion allows for nutrients and O2 to be between adjacent cells. No need to be directly next the capillary, if your neighbor, or neighbor's neighbor is.
Many forms of multicellular life have no ciculatory system, for example jelly fish. Our advanced ciculatory system allows for more efficient transfer over our large volume, but especially in less active tissue, cells may be far from a capillary. | 187 | 233 |
|
CMV: Most advice given to women about staying safe isn't 'victim blaming', it's crime prevention | [Victim blaming](https://en.wikipedia.org/wiki/Victim_blaming) occurs when 'the victim of a crime is held entirely or partially at fault for the harm that befell them'.
Victim blaming absolutely, 100% happens. And, of course, it primarily happens where the victim is a woman and the crime is sexual assault/harassment. I have no doubt that women are disproportionately subject to victim blaming, because there are many sick deluded people (mostly men, I'm sure) who have a disgraceful view of sex. This should end, and we should call out anyone who targets women in this way.
However, I believe the extent to which this is a widespread and/or societal problem is overstated. Significant amounts of so-called 'victim blaming' is well-meaning, non-sexist, pragmatic crime prevention which individuals and institutions broadcast equally for every other crime.
This might be best illustrated by an example. Police departments everywhere give advice towards preventing your home from being a target of burglary. Lock your doors at night, install alarms, leave the TV on when you go on holiday, install cameras, install a motion-activated light, get a dog, put a sign up, advise your neighbours when you're away.
None of this invokes responsibility. It's so obvious that a burglar is criminally and morally responsible for a burglary, that it doesn't even need to be said. The police aren't saying that if you don't lock your doors at night you're responsible for someone coming in and taking your TV. They're saying that burglars unfortunately exist, and they look for empty houses, so leaving a light on will make your house less of a target.
And the thing is, everyone understands the rationale behind burglary PSAs. We don't respond by saying *'Stop burglars burglarising, don't blame me for being burgled! I have the right to leave my door wide open at night!'*. We know that the police aren't saying that we don't have the right to leave our house unsecured. We know that the police are trying to stop burglars burglarising, as well as giving advice to the public. We understand that they're giving us advice towards reducing our likelihood of being victims to the criminals who unfortunately exist.
Why do we neglect this pragmatic reasoning when the crime in question is sexual assault? There's no doubt that a girl walking alone, at 3am, whilst intoxicated, looking beautiful, is more likely to be a victim of sexual assault than the sober girl who gets in a taxi with her friends. **I wish so much** that we lived in a world where it was equally safe to take both paths. But we know that it isn't, in the same way we know that it's less safe to leave our doors unlocked.
So why, exactly, do we conclude that giving women the same crime prevention advice that we give to homeowners is sexist victim blaming? Change my view! | The difference between victim blaming and crime prevention is when the advice is given.
Was the advice given before a potential crime or after the crime?
Giving advice before a potential crime is crime prevention as it diminished potential crime.
Giving advice after the crime is judgemental, or redundant. You are not trying to prevent a future crime, you are just making the victim feel guilty as a "lesson". Worse, if your advice is wrong, the victim now has to defend themselves.
Of course both can overlap but it boils down to two statements : "how can we do better?" Versus "why did you choose to be victim?". The information might be the same but the intent of the question is not. One is a desire to help, one is a desire to judge. | 37 | 84 |
ELI5:How is the Holocaust seen as the worst genocide in human history, even though Stalin killed almost 5 million more of his own people? | After reading the other comments i try a different approach.
What was different about the Holocaust and other genocides?
I think a big reason for the different perception of the Holocaust is how it was done and by whom. The Nazis conducted the Holocaust in a very bureaucratic manner. It was very methodical. Very methodical done by very smart people. People who arrived at the camps were sorted and marked like cattle. The Nazis searched for jews everywhere. Everywhere! Escaping this was hard when you didn't flee early enough. They searched for them even if they posed no threat just to get all of them. They hunted them everywhere even in the occupied regions. Compared to Stalin it wasn't about silencing/killing people who were deemed a threat to him or the system, it was about exterminating an **entire race**. Just think about it, it was about purifying an entire continent. Killing everybody who was not regarded worthy to live. This was done not by taking every jew and shooting him on the spot, that was not efficient. The Nazis tried to find efficient almost **industrial** ways to kill millions of people. They were first used to build weapons. Weapons like the V2, which were revolutinary at this time. See the contrast here? Brilliant weapons developed by smart people, the "same" people trying to exterminate a race. Futuristic weapons, which would later be the basis of the apollo program, build by tortured slaves, where do you find these kind of contrasts? Iam no expert of Holocaust or other genocides but other holocaust often seem more "improvised". Also a big reason for the different perception is where it was done. Germany. Germany is now a western country, always known as a powerful industrial country. The country of the "Dichter und Denker". A country with many of the greatest poets and composers. Before the war a big part of the nobel prices went to german scientists. Germany was a respected powerful country with open minded people. But some years later....
Genocides were often "Mittel zum Zweck" getting rid of an opossing political force and their basis for example. For the Nazis and Hitler it was the "Zweck". Thats a big difference to other genocides as well. When the red army advanced in the east and the western allied in Italy and France the Nazi intensified their killing even if it wasted a lot of war ressources because if they the lose the war they at least kill as many jews as possible. Think about that. | 2,105 | 2,131 |
|
ELI5 Why we're more likely to get ill during colder seasons | Why is it that whenever winter-time comes, people suddenly start getting ill? How does cold affect our immune system? | There are many compounding factors. The strength of your immune system isn't really one of them, actually.
The biggest is that we tend to clump up inside in cold weather. So there are more people in less space sharing germs.
Sunlight and heat are both good at killing viruses as well, so viruses live longer on surfaces indoors. | 32 | 45 |
The tensor is property of many fundamental forces in QED, but it is not explained in readily graspable terms... | Does anyone here have a good way to explain what a tensor is, what the different ranks and classes of tensors in normal terms?
Thanks in advance. | A tensor is basically the general term for vectors and matrices. A tensor has a rank which is the number of dimensions it has: a rank zero tensor is a scalar (number), a rank one tensor is a vector, a rank two tensor is a matrix, and higher rank tensors don't have fancy names.
Generally in physics, each row or column of a tensor corresponds to a specific dimension in space. For example, the velocity gradient tensor describes how the x component of the velocity changes in the x direction, how it changes in the y direction, how the y component changes in the x direction, and how the y component changes in the y direction. | 11 | 17 |
I believe that being physically unattractive is a serious disadvantage, not unlike being born into a low income family; CMV. | **MY VIEW HAS ALTERED**: Sorry for the long wait, but I managed to read at least 90% of the responses and have to actually admit my view has been altered somewhat. I still believe that unattractiveness is a serious limitation, but I will say that I undervalued the negatives of being physically attractive, particularly over-objectification. Based on the comments, it has confirmed that attractiveness also becomes irrelevant at some point depending on how you measure success.
-------
To preface, this is not the rantings of an ugly troll who can't get a date - just so you know, yes I am below average but I've been in a wonderful relationship for five years with someone quite hot (I say that because she knows my reddit username - hi honey!), but that is not the main argument I am positing. I will be posting a lot of studies from my time in psychology, but the original reference is stored away in a pile of boxes. I will be updating with a digital link to the article over time, and if it is made available for public viewing.
The main focus of my view is physical attractiveness as a social capital. Without a doubt, there is a conscious and unconscious preference towards people are physically attractive, this goes for men, women, children and even [chickens](http://cogprints.org/5272/1/ghirlanda_jansson_enquist2002.pdf), so to an extent we are all shallow, at least on first impression; but this is often a pivotal stage for the continued success of any relationship. And yes there is a general guideline for physical attractiveness, while body-types may differ based on culture and upbringing, features (especially of the face) generally have a normality for attractiveness, the less you deviate from that ratio - the better.
I understand that attractive people are subject to certain prejudices, and I am aware that some of them are:
* Over-objectification
* Attractive people are viewed as less intelligent. There is an interesting study as well demonstrating an inverse relationship between the amount of skin shown and perceived intelligence.
But these issues are easily manageable, unattractive people however are prone to the serious issue of being invisible or dismissed. Like being born into a wealthy family, attractive people will always have better opportunities, pre-established social connections and status, will initially command more respect, the *potential* for more exposure to culture and education and a significantly easier time achieving long term goals due to the aforementioned.
* Because I have an ethnic name, I actually get a significantly reduced number of callbacks for interviews when using my legal name in my job application. I replicated this from a study that looked into the same issue, by creating two identities and using a neutral last name i.e. Smith, on the latter. I believe unattractive people face a similar problem of being able to get their foot through the door. Studies show that people will immediately notice the tallest person in a group, unless there is significant case of a person being short, e.g. dwarfism. Unattractive people are often overlooked, and people are less likely to remember them.
* Unattractive will have more issues regarding self-esteem. [The detriments of being complimented on physical appearance](http://www.nerve.com/scanner/2009/09/28/study-says-calling-women-pretty-makes-them-more-likely-to-reject-you) aside, not being viewed in a favourable light, especially in adolescent to early adulthood can have long lasting ramifications - especially when people learn that appearance plays a big role in success. There are things people can do to even the playing field - wear nice clothes, consider the significance of scent to desirability, the use of wit and rhetoric - but these are things EVERYONE has to consider. Adhering to these rules does not give you an edge over anyone else observing them as well.
* People are nicer to attractive people, whether they realize it or not. Studies show that we want approval from attractive people, because we implicitly believe that their opinion is of more value. Just to add a tangential point, having attractive friends, like in one study where participants were asked to rate people based on their Facebook friends, also improves people's perception of you. So being attractive actually helps those around you.
* Unattractive people will always have to try harder, this goes double if you're not-good-looking and are of an ethnicity that is not of the norm of your country/region.
Just to counter a likely argument I'll hear, I am aware character and virtue are more valuable traits in the long term. But my argument is the limitations set by a person's looks are much more difficult to overcome, create a massive gap in terms of social capitol assuming other variables remain constant, and is virtually permanent.
Sorry for the long post, but I wanted to be thorough with my argument, and I actually had several more points - but I think you get the gist.
EDIT: Wow, I did not expect this response. Thank you guys/gals. I was going to keep following the thread, but I ended up falling asleep.
Firstly, I'm glad we all agree that superficiality is common, but at the same time it is depressing by it's unanimous acceptance =/
Secondly I should **clarify the argument to allow for more responses**: Yes I am stating facts, but there is a reason I consider unattractiveness akin to low income. Wealthy upbringing will always have the potential for a better life, so that presents an existential problem to /u/WhyNotWhatsWrong query. If you haven't heard of it before, the term for a person who is poor and becomes wealthy is called a silver-tail; the issue with them is that they are never really ever accepted within their new community. This isn't a fact, this is one part of me that actually came to this conclusion without strong empirical evidence. While not directly related to low income situation ,I also wanted to point out that I mentioned that it is a permanent problem, to which to **there is no solution**, well technically there is one but it requires an entire rework of the architecture of the brain.
EDIT 2: I also wanted to address a common claim, that attractive people are boring, superficial or are more prone to negative quality X, this is simply not true. Too many studies have shown virtually no character difference between the population, *especially* after high school. | Adversity builds character?
I mean, yeah, all of what you wrote is true. Unattractive people have more of an uphill battle in life, on all fronts; there's really not much to dispute there. But is that a bad thing on an existential level?
| 125 | 569 |
ELI5: If sweating exists to control body temperature, why do sometimes people sweat from their feet or hands even though they are frozen cold? | If you've been doing physical work, your core temperature will increase, largely regardless of the outside temperature. the natural response is to sweat to remove the excess heat. since your head and feet (and hands) tend to have alot of capillaries near the surface of the skin, they tend to be much more efficient at removing excess body heat compared to the rest of the body, where blood vessels are deeper. | 30 | 193 |
|
With the latest recommendations, why is it a bad idea to use OAuth2 for authentication? Why is OIDC a good idea instead? | I've recently been setting up an authorisation server for a startup I'm launching. Now, we could have just used something like Auth0 and been done with it (temporarily) in an authentication sense, but knowing that we have some complex needs surrounding both authentication and authorisation we opted for creating our own "IAM" service.
The obvious first step here seems to be making an OAuth2 server. We have several client applications, including a dashboard application that's a single-page application. We wanted to delegate authorisation to protected resources via that client on behalf of a user, and that is of course exactly what OAuth2 is intended to be used for.
However, another requirement of that dashboard application is that it shows the current user information somewhere (i.e. their name at least) so they're aware of who they're "logged in" as, etc. Now that on its own isn't authentication - I get that, it's more like pseudo-authentication; it's just showing the entity interacting with a client application which user originally consented to that access token being used.
I'm currently struggling to understand:
* Why using OIDC to "authenticate" provides any more "authentication" than OAuth2?
* Why using OAuth2 would be any less secure as a mechanism for authentication?
My current view on the first of those questions so far is that OIDC seems to be for the benefit of a client application. As in, the client can say if it received an ID token that the user has authenticated with it because the only way it would get one is either from something like an authorization code flow initiated by a user, or a refresh token flow (which should only be possible to be initiated by the client that made that initial authorization code flow request).
But what difference does that make to a client in that case when compared with receiving an access token alongside a refresh token (either via the refresh token grant, or the authorization code grant)? All of the above also applies to the that flow, i.e. the only way you get a new access token alongside a refresh token is by something like an authorization code or refresh token flow, and you can only do this if the user themselves consented to that initial authorisation code flow. The authorisation code and refresh token will still be bound to that specific client. The access token itself being a JWT is fine too, they're all unique, their authenticity can be easily verified, and depending on how you implement them they're still trivial to revoke (e.g. by storing the "jti" claim, and still verifying an access token with every request to a protected resource). What difference is there then between being able to use the token endpoint at all, and what OIDC does in terms of authenticating the user?
The only argument I can think of is that OIDC standardises this approach, meaning it's easier for third-party clients to consume identities from your OIDC server, and it allows you to use off-the-shelf client libraries, etc. This point is actually one that resonates with me, because it would make developing clients a lot easier and probably more secure because those libraries will be better battle-tested. This is to say, OIDC makes it easier to consume identities from an identity provider in a standard way (e.g. for identity federation).
The second of these questions, I cannot wrap my head around. Quite a few places have said that it's less secure, and gone on to give some reasons why it's insecure (and then explained how to avoid those issues with OAuth2 itself), but most of the content I've found on this topic seems to be quite old (i.e. before implicit flow was deprecated in favour of using the authorisation code flow with PKCE - which is the way I'm currently tackling it). I understand the potential loopholes in OAuth, but the spec does cover how to avoid many of these (one in particular that people seem to keep talking about is how according to the OAuth2 spec, authorization codes can be re-used in different clients as long as they're valid - but actually the spec does say ["The authorization code is bound to the client identifier and redirection URI."](https://tools.ietf.org/html/rfc6749#section-4.1.2)).
What is OIDC doing to make any of this more secure anyway? An access token is still an access token right? If you have an insecure OAuth2 implementation, it doesn't seem like layering on OIDC is going to help with that.
I'm completely content with the argument that OIDC just standardises this authentication approach, but I can't tell if I'm just missing something that actually makes OAuth2 insecure, or a *bad* choice for authentication in some way other than the standardisation argument I've mentioned above. It is certainly entirely possible there's some kind of situation I'm not thinking of where the distinction and addition of the ID token seems more useful from a security standpoint, and would really appreciate some input from people that are more knowledgeable on the subject than I am after spending a week building an OAuth2 server... | OIDC gives you standardized information in the ID token. This means that you don't have to introduce an internal standard on what's contained in your token, but external and internal software can rely on the same fields | 11 | 52 |
ELI5: Why is it easier to get a job when you already have a job? | I've heard this countless times, written in articles and from recruiting professionals.
Every time I've been on an interview, they ask me when I'd be able to start. When I give them a date two to four weeks away, their face always drops and I can tell they're no longer considering me because they need someone sooner than that. I know that my personal anecdote doesn't invalidate something that's known to be true but of the many interviews I've been on, I've only found that having a job already is cumbersome to whoever you're interviewing with. | It's easier to get a job when to have a job because you're in a stronger negotiating position. You don't have to have the job, you already have one.
Also, if you encounter an employer that is loses interest because you can't start for two weeks, you should feel lucky. You're dodging a bullet. This is an indication that the place has high turnover and they value getting a warm body quickly more than getting the right person.
Then you have to think to yourself... "there must be a reason why they have that kind of turnover." Any reason you come up with is likely to be a reason you'd want to work somewhere else.
No good employer will have any problem with waiting 2-4 weeks to bring on a good employee. | 267 | 215 |
ELI5: How was the first operating system created if we didn't have anything to code it with? | you can write code in binary (slowly) and make a low level programming language. With this program you can write progressively more complicated programs so on and so on until you write an operating system which is more or less a program that runs other programs. | 123 | 135 |
|
What body system does fat belong to? | If they can be part of different systems, are there other examples of tissues that are not strictly monogamous?
| Endocrine system generally, but it's also important connective tissue. Fat cells derive embryologically from mesoderm (there are three basic embryologic tissues). Also, you may be interested to know that there are two types of fat (let's call it adipose)-- white adipose and brown adipose. White adipose is typically what you think of when you consider fat. It's the stuff that's under your skin, in your belly, thighs, around your heart, kidneys, and etc. Brown adipose on the other hand tends to be around only when you are an infant, and it actually actively burns carbs and fat to create heat. It's brown because they contain iron rich mitochondria, which are the cellular machinery for burning through chemical energy. People have tried to harness / reactivate this stuff over time, and it's a pretty interesting research field in itself.
If you're interested in some peer reviewed lit on the subject, see: doi:10.1038/nm.3361 "Brown and beige fat: development, function and therapeutic potential"
As to your question about tissues not being strictly "monogamous," there are tons of examples!-- blood, blood vessels, nerves, muscles all comprise important parts of various organs. Generally, various tissues compose an organ, and organs work together in organ systems to carry out a specific function. For example, renal tubules are a tissue but they work along side smooth muscle, blood vessels, neurons, and endocrine tissue in the kidneys (an organ), which are an important part of the renal or excretory system. The human body is a wonderful thing. | 836 | 2,334 |
ELI5: Why do we need to consume fat if excess carbohydrates are ultimately stored as fat? | My understanding is that any carbs that aren't used for energy are converted and stored as fat. Hypothetically, could a human just survive off of protein and a lot of carbs? | Fat has two basic uses for the body: energy storage and ingredient for stuff, like hormones. The second use can't be fulfilled by stored fat, it must be dietary (eaten) fat.
And no, you can't live without fat, there's even a thing caused "rabbit starvation", which is literally people starving to death because they only ate rabbit meat, which is VERY lean, for a long period of time. | 97 | 41 |
ELI5: How do CEOs like Mark Zuckerberg get paid? Do they receive a paycheck? How often do they get money from their company? | I know this question shows a lot of financial naivety in how stocks work, but that's why I am asking. | Salaries for C-level (think CEO, CFO, etc.) officers at publicly traded companies (things on the stock market) are generally publicly disclosed, as part of what is required to be a public company.
You can look up the salaries of all of these people. However it will be a bit obscured, for lots of reasons. Their salaries are generally a combination of salary plus stock (and/or stock options, which is more complicated so lets not worry about that).
So basically, most C-level people get paid some combination of: "base salary" + "some stock" + "some bonus or other compensation"
All of that together is regarded as their official compensation. Often, most of it is in stock and/or bonuses due to how taxes work on those vs. how taxes work for salary, its all a bit of a game about how they get paid to maximize pay while minimizing taxes.
OK, one more aspect. Many C-level people also get to charge expenses to the company. This is a bit of a racket, but its at the end of the day, just another way to dodge taxes and such. pretty much, many C-level people can charge some (or all) of their living expense to the company to pay. Be it their house, cars, travel, fun, dinners, etc. Again this is all known, nothing interesting, and just part of what they negotiate as their salary. It really isn't that interesting, everyone knows the score, knows the situation, and it is what it is
| 24 | 25 |
In your opinion, which is currently the best country for an economic migrant to go to? | I suggest that an important factor is how well-accepting a given nation is to immigrants. It does not matter if a country has a strong economy and job market for native-born citizens, but keep immigrants out, or treats them like second class citizens. So on this basis, I'd suggest Canada and Australia as being historically friendly to immigrants. | 23 | 76 |
|
ELI5: What does an e-sport team coach do? | Analyses and organises play and practice. Sometimes plays a minor role as a manager (including PR, travel and lodging arrangement). Basically, like any other coach, they take a birds eye view of their team, take what they see and then delegate roles and improvement strategies on that basis. | 12 | 17 |
|
ELI5 Why is it that diabetes causes so many other health issues? | Well, first you need to know that there are two types of diabetes. Type 1, and Type 2.
Type 1 is an autoimmune disorder. Basically, the immune system sees the cells in the pancreas as a foreign invader and begins attacking them. Those with autoimmune disorders are more likely to develop other autoimmune disorders like a specific type of arthritis, celiac's, hypothyroidism, etc.
The next issue that occurs is from too much glucose in the blood. This can be seen in both forms of diabetes. The reason for cardiovascular effects is because too much glucose reduces the amount of the vasodilator hormone. Essentially, the blood vessels are unable to expand properly which increases blood pressure and will damage the blood vessels over time causing them to become too narrow.
It's important to note, however, that diabetes doesn't necessarily cause other health issues. Besides the whole one autoimmune disorder increases likelihood of another, it's the high blood glucose that does the damage.
| 24 | 22 |
|
ELI5: How does it take over 600 gallons of water to make a single hamburger? | Most of the water is used to raise crops like alfalfa, which are then used to feed the cattle all their lives, which are then killed to make meat. (The cattle drink every day too.) So it's a very indirect, wasteful process. | 45 | 26 |
|
[LOTR] During the Battle of Helmsdeep, why did they make a big deal about saying the women could fight and handle a sword, but then locked them all away in Helmsdeep and started fitting the children with armor and weapons? | You have to understand their culture. Although they may have been a fierce people they have to think about the long term affects of sending their woman out to die. As you recall in that episode there were a few scenes that set the stage for the battle and how important it was. | 51 | 63 |
|
Religious people are often just as logical as non-religious people, they just start from different assumptions. CMV | For context, I'm an atheist but I find that many of my non-religous friends seem to think that if someone is religious they have to be completely Illogical, but I don't think that's the case. They actually are logical, they just start from a different set of assumptions.
For Example:
A=B
B=C
A=C
Is valid
But
A ≠ B
B= C
A≠ C
Is also completely valid but you wind up with different conclusions. For Christians, they start with the assumption that say, the bible is true or at least a truthful if metaphorical guideline. And since atheists reject this premise (Even if it's they're justified in doing so) they wind up with rather different end points. But neither Christians nor atheists commit a error in reasoning here. So CMV! | Assumptions can themselves be judged on terms of rationality. Christianity assumes, as an epistemic standard, the contents of a book, with no prior principles to show why the contents of this book are necessarily true and should not be judged by their own merit.
Atheism, since it denotes a lack of belief, does not depend necessarily on any particular epistemic standard, but a very commonly held epistemic standard among atheists is empiricism which states, in simple terms, that experience is the base of all knowledge. Reasoning from the available evidence, one is not able to find anything that resembles, to any surprising or convincing degree, the unusual things stated in the Bible; in particular, there is no solid evidence of God.
I suppose if you want to claim that empiricism and "the contents of this specific book are true a priori" are equally rational epistemologies, we can discuss that, but if you concede that they are not, then your case falls apart. | 54 | 38 |
Why do some materials conduct electricity while others do not? | I've heard that it is related to the energy levels of electrons or the lattice of the material among other things, but I do not have a good answer as to why some materials conduct electricity while others do not. It is quite difficult to find information relating to electricity on the atomic level. | When you have a bulk material like rubber (insulator), silicon (semiconductor), and copper (conductor) the electrons energy levels of the individual atoms form energy bands when considering the bulk properties of the material. To move electrons through a material you must promote them from the valence band to the conduction band, in an insulator the band gap is large it takes a lot of energy to promote an electron, with a semiconductor the band gap is small taking only a little bit of energy to promote an electron, and in a conductor the valence band and conduction band are touching so only a very small amount of energy is required to promote an electron. | 15 | 41 |
ELI5: Why are Black American families on average living in poverty more so than other American Ethnicities? | It hasn't been that many years since discrimination against black people was legal in most of the nation. Those sorts of laws have a large impact. You had many black people who didn't get equal educations to white people, who weren't getting hired for well paying jobs, who didn't have hopes for the future because of racist laws and racist policies in workplaces. That has an impact. If you didn't get a good job, you raise your children in poverty. And it is difficult for people to escape the cycle of "born poor, live in a bad neighborhood, get married to another poor person, and have poor kids."
It will take generations for real change to happen in this regard. | 59 | 34 |
|
If your skin temperature is lower than usual and you stick your hand/foot in hot water, does it do actual damage? | I was thinking of this as I went to take a shower last night and my feet were cold. The water wasn't hotter than it normally would be but it felt like sticking my feet in boiling water. Is it just the sensation or is there actual damage being caused? Also, what exactly causes this to happen? | Sensory or neural adaptation is a change in time in responsiveness to a constant stimulus, for example, what your clothes feel like on your skin. When your feet are cold, the neurons that transmit a feeling of warmth are not firing. When you submerge them in warm water, these warm-sensing neurons begin firing rapidly signaling heat, but you're also signaling a rapid temperature change. Because of the rapidity with which your body was sensing the rise in temperature, nociceptors, or receptors that signal pain, became activated, warning you that something may be potentially wrong.
Unless you are actually using boiling water, there is likely no damage being caused. | 19 | 29 |
How are permanent magnets formed? | Plus why do they lose their property on heating | Permanent magnets are created by heating a ferromagnetic material to a specific high temperature while exposing the magnet to a strong electric current which is responsible for aligning the atoms in the magnet in a single direction.
As the magnet cools it will maintain this single direction, causing magnetism for the whole material.
If you heat this magnet again, the high kinetic energy causes the atoms to scramble around in a looser state, causing the atoms to unalign, thus the magnetic fields cancel out, and the material is no longer magnetic.
An electric current, and it’s resultant magnetic field is what causes the atoms to align in a ferromagnetic material, to make that material magnetic. | 202 | 247 |
ELI5: How you become eligible to be knighted and the process that follows | The most common Order of Chivalry is The Most Excellent Order of the British Empire, which has five "ranks." From highest to lowest, these are:
1. Knight Grand Cross or Dame Grand Cross of the Most Excellent Order of the British Empire (GBE), limited to 300
1. Knight Commander or Dame Commander of the Most Excellent Order of the British Empire (KBE or DBE), limited to 845
1. Commander of the Most Excellent Order of the British Empire (CBE), limited to 8,960
1. Officer of the Most Excellent Order of the British Empire (OBE)
1. Member of the Most Excellent Order of the British Empire (MBE)
GBE and KBE/DBE automatically make the recipient a knight (male) or a dame (female), which allows them to use the title "Sir [Name]" or "Dame [Name]." Note that these honorifics are used only before the first name, so you would, e.g., refer to Sir Patrick Stewart or Sir Patrick, but never Sir Stewart.
As part of the British honours system, membership in the Most Excellent Order of the British Empire is a **means of rewarding individuals' personal bravery, achievement, or service to the United Kingdom and the British Overseas Territories**. All members of the order are appointed by the current British monarch, who is Sovereign of the Order. Typically, they do this under the advice of the governments of Britain and the Commonwealth. No more than 858 Officers and 1,464 Members may be appointed per year.
Other Orders of Chivalry include the Order of the Garter and the Order of the Thistle. Some Orders of Merit also come with an honorary knighthood at their highest ranks. Men may also be knighted separately from membership in one of these orders, giving them the rank of Knight Bachelor (Kt).
Only citizens of the United Kingdom and Commonwealth can be full members of these orders. Foreigners are considered honorary members only, and while they may use the letters after their name, they do not take the title of "Sir" or "Dame." | 85 | 214 |
|
ELI5: What's going on when you get that tingling feeling in your body after seeing/hearing something you feel is profound? | It's kind of difficult to explain but whenever you hear some very good lyrics in a song or you see a movie trailer that absolutely hooks you this feeling starts. Almost like a kinda good tingling feeling in your head and body, also my peripheral vision will start to fade when this happens. What is my body actually doing when this happens? | Some people call it autonomous sensory meridian response (ASMR). No one is really sure why this happens, but it occurs because your senses have encountered some stimuli (visual, auditory, etc). Some psychologists support its existence and say it produces similar effects to meditation, but there is not broad agreeement about why this happens. | 53 | 178 |
ELI5: Dreaming for people who were born blind. | How does someone who has never experienced visual stimuli their entire lives dream? Is it in sounds, feelings, textures, the shapes of things they've experienced through touch? | I work for a state school forr the Blind. All of the students that have been blind from birth say that they just dream in sound. Same goes for the deaf community. They just dream in pictures and no sound. | 11 | 25 |
ELI5: Why are some people more intelligent than others? Why don't our brains all have the same capability to absorb and use information? | The capacity to absorb and use information would be determined genetically, and different people have different genes. Furthermore, regardless of theoretical capacity, the actual growth of your brain is greatly affected by diet and nutrition (especially early on). Lastly, your capacity for absorbing and using information is useless if you aren't exposed to information in the first place.
In short, your actual intelligence is a combination of internal and external factors, both of which can vary greatly from person to person. | 30 | 40 |
|
ELI5: How are surfing competitions judged if surfers don't always get the same waves as each other? | As a surfer, you have to pick the wave that best suits the tricks you want to perform. That's part of the skill, being able to read the wave. Just like how fishing competitions rely on the fishermen picking the best fish to keep, not just catching fish. | 24 | 38 |
|
ELIF "A Theory of Justice" by John Rawls | Lot's of people have been writing about how to set up society and divide money, but a common criticism is that the people who supported those ideas where the people who'd benefit from them.
What Rawls said, was "what if we decided on what society was like, if we didn't know what our position in society would end up being?"
Basically, he argued that if people don't know what their position would be, they'd all agree on at least three basic rules: firstly, that everybody would be free to do whatever he wanted, so long he didn't bother other people with it. Secondly, everybody would have an equal say in decisions, and thirdly, people only get to earn more money for their work, if earning that money is justified by being for the benefit of everybody. | 11 | 20 |
|
ELI5: why is it fairly easy to keep track of how much time has passed while awake, but a short nap of even 5-10 minutes can make it feel like hours have passed? | While awake you’re able to pick up on things like the brightness coming in from the outside and are participating in tasks that you’re likely familiar with and can anticipate the duration. Probably more importantly, you likely have a computer, wall clock, or cell phone showing you the time, whether you’re deliberately checking it or not.
When you sleep, if you’re not a regular napper, you will probably assume you’ve been asleep for the normal amount of time, since you’ve been unconscious to the queues that normally help you track time. This is especially true if you did not decide to fall asleep and wake up to darkness with nothing to tell you what time it may be. | 20 | 55 |
|
How did they film the atomic bomb ? | I don\`t know if this is the right subreddit . But how did they film the atomic bomb explosion back in the day without ruining the footage / camera , And who was the poor soul who went and fetched them
I am referring to this close up footage when you see the cars/ trees blown away by the shock wave
[https://www.youtube.com/watch?v=5gD\_TL1BqFg](https://www.youtube.com/watch?v=5gD_TL1BqFg)
[https://www.youtube.com/watch?v=ztJXZjIp8OA](https://www.youtube.com/watch?v=ztJXZjIp8OA)
Thank you ! | Typically through some combination of reinforced concrete, a small optical aperture, a suitably tough window material, and/or mirrors to deflect the light so that the camera can be more deeply protected. Also lead shielding to protect the film from X-rays, and/or emulsion that is less sensitive to X-rays. | 55 | 54 |
[Harry Potter] Why does the school bother grading assignments, when career paths are determined by OWLs and NEWTs? | Even in OotP and HBP, it seemed the only determining factor in course eligibility was a student's scores on these standardized tests. If that's the case, then in theory, I could skip all assignments and still end up Head Auror with the right test scores.
EDIT: I've learned form /u/MugaSofer that the UK school system (or maybe just the Irish) also similarly disregards class grades. I'm an American, and in the States, GPA is very important when considering future opportunities (either employment or higher education). That's why Hogwarts' system seems so strange to me. | So the teachers know if you understand the material. A smart student could skip out on a lot of work. Fred and George basically did this, they went to class and obviously understood the material but just didn't give a shit. | 100 | 104 |
ELI5: Why do nails get softer after being in water or easier to cut after taking a shower? | Our nails are made of layers that make them strong and help them keep their shape. One of these layers has keratin cells, which is a special type of cell kind of like bone. These cells are very thin and let water pass through to keep the nail hydrated and healthy.
If we have a shower or go swimming for a while the nails get over loaded with water and become soft until it can be absorbed. | 145 | 247 |
|
ELI5: Why do people and animals get comfortable? What is comfort? | Comfort is a lack of hardship, danger or stress. From an evolutionary point of view, avoiding dangerous situations is obviously beneficial to survival, so an animal that experienced negative emotions (discomfort) during these situations is going to try & avoid being in them. Feeling happy in a safe area means an animal would be more likely to stay in that safe area. | 57 | 120 |
|
CMV: the entire “humans weren’t meant to be monogamous” argument falls apart when you take children into account. | I often come across discussions that center around the fact that now humans live such a long lifetime, monogamy is unrealistic and out-dated. But every study I have ever read on the topic of childhood seems to prove children have the best outcomes in a two parent home with parents who have a good relationship.
I don’t see how this is compatible with the idea that marriage and long term commitment are passé.
If, as a species, we thrive best when raised by a couple, there must be SOMETHING to the idea of marriage. | The idea of children needing a home with two parents is more of a cultural aspect of western society than something inherent. There are other arrangements. Some cultures take a more community rearing approach where the individual parents aren't so important and children will be raised as children of the whole village. Another approach is to have stable polygamous relationships. They will be similar to monogamous marriages but will have more people involved so the children have several stable parents rather than just the two. | 365 | 436 |
[Star Trek] Why the Ferengi never had slavery? | > Quark: I think I figured out why Humans don't like Ferengi.
> Sisko: Not now, Quark.
> Quark: The way I see it, Humans used to be a lot like Ferengi: greedy, acquisitive, interested only in profit. We're a constant reminder of a part of your past you'd like to forget.
> Sisko: Quark, we don't have time for this.
> Quark: You're overlooking something. Humans used to be a lot worse than the Ferengi: slavery, concentration camps, interstellar wars. We have nothing in our past that approaches that kind of barbarism. You see? We're nothing like you... we're better.
Concentration camps and wars may not be good for business (other people's wars are good for busssiness), but slavery seems to be a thing that Ferengis would do. | The Ferengi have indentured servitude, and keep almost every feeeemale Ferengi in effective slavery. Quark is just arguing semantics in an effort to appear morally superior. He's like those weirdos who harp on word choice rather than subject matter.
E.g. "it's not pedophilia, it's ephebophilia." | 109 | 52 |
How is our liver able to regenerate itself, when our other organs cannot? | Many other organs can regenerate. For example, skin, bones, blood vessels.
But liver is the only internal (visceral) organ that can regenerate.
The reason for this is that the main function of liver is to remove ingested toxins from blood before they reach main circulation, and liver cells are relatively often killed off in that process. (Because toxins are, well, toxic.)
Most other organs have no strong need to replenish their cells, and as a result they are unable to recover from a significant loss. But again, organs that *do* have a strong need to replenish their cells (like skin) can (and do) regenerate from significant damage. | 36 | 30 |
|
ELI5: Does the Surface Tension of Water change (increase/decrease), as the surface area changes? | Does the Surface Tension of Water change (increase/decrease), as the surface area changes? Does Temperature also have any factor in this.
E.G. : The Surface Tension of a Graduated Cylinder compared to a Lake. | No but the ratio of the effects of surface area can change as the volume increases.
Temperature does affect surface tension. Surface tension is a result of molecules of water forming stronger bonds with other water molecules than with air. Therefore, breaking the surface of the water requires breaking some of those bonds. The bonds between water molecules are weaker when the water molecules move around really fast and spend less time bonded - as in hot water. Once water is boiling, all of the heat energy goes to breaking the water bonds and the surface tension is zero. | 10 | 40 |
[Star Wars] In what ways did the Empire do nothing wrong? | It provide peace, prosperity, and order to the Core Regions of the Galaxy. Petitions for the betterment for the citizens of the Empire are no longer hampered by bureaucracy and corrupt senators.
Military-wise, the Stormtrooper Corps and the Naval Corps are both meritocracy instead of relying on political connections and being a warrior monk of a debunked and fraudulent religion. | 35 | 43 |
|
[Warhammer 40k] Can vegans eat orcs? | Generally, veganism is built on the moral platform that you shouldn’t cause death or suffering to sentient beings for the sake of your own lifestyle. Since orks are sentient beings - even if they are sentient fungi - they would therefore be inappropriate for a vegan diet. However, since orks are also foul xenos, accursed in the Emperor’s sight, many of the more sternly orthodox leaders of the Imperium would regard recognising their sentience as heresy, and would therefore argue that eating their flesh is no more wrong than righteously slaughtering them in His name.
You still shouldn’t eat them, though. They taste terrible. | 37 | 17 |
|
CMV: Trying to understand yourself through your ancestry is meaningless | Some people take a DNA test, find that they have some high percentage of an ethnicity that they know nothing about or maybe didn't even know existed, then suddenly they identify with its culture. I think that it's meaningless and just another type of horoscopes.
My main point is that culture is lived and experienced, not inherited. If you find a high percentage of Italian ancestry in your DNA but have never been to Italy then you have absolutely nothing to do with the Italian culture. Your DNA test revealed absolutely nothing about who you are as a person.
In this sense, giving someone the citizenship of a country just because some of his ancestors belonged to it is meaningless and arbitrary. Italy does this. I think that if your grandparent's father was Italian then that doesn't make you entitled to the Italian citizenship in any way.
I'm assuming that the citizenship means more than just a document. But it seems like most countries think the same, since many will require you to know their language and maybe do a history test before being eligible for it.
I'm also not saying that understanding yourself is the only reason people take DNA tests or research their genealogy, but I think that it's the main reason (especially when it comes to DNA tests). | For some people, it helps give them a sense of belonging, especially for people who don’t know their ancestral roots, it can help give them a direction for a culture to explore and adopt.
Sure, it’s not the end all be all, but can give people some direction. | 31 | 81 |
How do linguists discover the phonetics of ancient symbols? | Typically via comparison with known languages. Bilingual (or trilingual) inscriptions like the Rosetta stone provide a basis for sound when words like names are transliterated. Monolingual inscriptions in a different script can be helpful, like an Egyptian name written in Greek. You can also find words in surviving languages: Coptic is a surviving language related to that of Egyptian hieroglyphs, and even some unique words in Egyptian Arabic are found to be related to the ancient language. Clues can sometimes be found based on context inside a text, like rhyme or onomatopoeia or puns or confused homophones or whatever else a careful reader may find.
The examples above are all about Egyptian, as it's the most well-known "rediscovered" script, but others will have gone through the same process, being more or less difficult depending on how related those languages are to existing ones and how much written material survives.
Reconstruction of the sound of an ancient language, of course, is far from precise. Language is always changing, and especially in the pre-modern world varied from place to place. Saying something was pronounced as such can only be sort of an idealized approximation at best. | 20 | 25 |
|
Does the wealth of the ultra wealthy actually harm normal people? | When people have a bunch of wealth (on paper), but they aren't actually chewing up resources, does it even matter to poorer normal people? Are poorer people actually getting deprived of goods and services? What is the effect of people accumulating enormous amounts of wealth on paper? | Wealth can be invested in making new goods and services - e.g. building a factory, or a piece of software or it can be invested in buying existing assets.
Building factories, software etc, typically results in hiring workers, paying them wages, paying other firms for parts and so forth, and thus the money circulates.
Buying an existing asset for, say, $1m, means that someone must have sold said asset for $1m. Therefore the seller has $1m in money to do something with (this probably includes the seller paying costs like commission, legal fees, taxes, etc). While they might turn around and buy a new asset of their own, at some point the $1m is going to be spent on investment in new assets or on consumption.
That said, the processes that produce paper wealth can be harmful - for example the restricted housing supply that drives up house prices deeply effects poorer people. The issue there is the housing shortage in and of itself. In other words, deeper details matter. | 58 | 80 |
ELI5: What dictates the power of passports? | Do governments decide what countries could visit their country visa-free or is there a process on deciding the strength of passports? Is it based on the power of a country’s currency and economy? | Governments decide based on mutual agreements. IE, 2 countries have good relations, trade is good, people are happy. They decide to have a visa free travel for both sides to encourage growth and lessen burdens on your everyday travellers. Hope this helps. | 150 | 138 |
Why does a pot of water or tea pot make the most noise right before the water reaches boiling? | Then it seems to get quieter once it reaches a rolling boil. | Assumed: a typical configuration, where heat is applied by conduction through the bottom of the vessel. The water near the bottom is warmed by contact with the heated surface. This warmed water rises, cooler water drops, and this convection distributes the heat energy.
When the average water temperature approaches the boiling point, small parcels of water near the bottom will acquire just enough heat to be converted into small bubbles of steam. These small gas bubbles cool as they rise through the cooler water, and condense back to liquid.
As the average water temperature rises further, less energy used to raise its temp, and more is available to vaporize it. The steam bubbles grow larger and the water temp grows hotter. The bubbles *nearly* break the surface before collapsing/condensing back to liquid.
It is these percussive, collapsing bubbles of steam that you you hear. When the bubbles collapse, the water slams into itself and, being a non-compressible liquid, converts that energy into sound waves.
When the bubbles of steam begin to make it all the way to the surface, the noise diminishes. When all the steam makes it to the surface, the sound stops
| 24 | 26 |
Want to leave academia, how to talk to post-doc supervisor? | I’ve been in this post-doc for 8 months and while it’s not going poorly, I don’t think it’s going all that well either. I’m increasingly feeling like this type of theoretical research (and chasing grants) isn’t what I want to be doing for the rest of my life.
There is an internal posting at the University where I’m doing my post-doc for a director of career and professional development services for post-docs and it feels like a great fit with my experiences, but I’m not quite sure what the protocol is for telling my current supervisor and/or fellowship program manager. I want to stay in the area because my partner is here, so I’m nervous about burning bridges and sabotaging my current job/future prospects if this opportunity doesn’t work out. What’s the protocol here for informing my supervisor? Up front? If I get an interview? Thanks! | You have two options here:
Be forthcoming and up front with your advisor. Tell them that you just aren’t feeling the postdoc and that continuing in the long term would probably waste both your and his/her time. Try to line up a few things if you can, but if it’s just the one thing discuss staying in lab while you try to pursue it/an alternative if that position falls through.
This, of course, is risky because your PI may or may not be onboard about you leaving so soon.
The second option is to apply and, if it comes to it, interview at the job without discussing it with your PI. This isn’t unheard of and it is understandable why someone would do so. If you secure the position, make sure to give your PI advanced warning. Try to hold off starting by a month or two so that you can wrap up and transition whatever your current project is. Unless your PI wants you to just leave, this should help make the exit less stressful and prevent anyone from applying fire to any bridges.
Our lab just hired someone as a research associate from his postdoc. He explicitly included in his application that his, then current, PI was not to be contacted about the position or his interview. He gave his PI about a month’s notice that he was moving on after he received an offer. No one here found it weird though.
It’s impossible to give you the “right” answer because only you know what you truly want and how your supervisor is/may act.
Hope you figure it out. | 27 | 60 |
Can light be infinitely brighter? | Is there a certain point where light cannot become any more bright? | Brightness is determined by the number of photons you see. If you have enough energy to power whatever is outputting the photons, you can have as many as you want. Any limit would be practical rather than theoretical. | 23 | 45 |
Books (or the written word in general) are not inherently more "intellectual" than any other form of media. CMV | I saw [this](http://www.reddit.com/r/pics/comments/1dzik1/perhaps_the_kids_will_be_alright/) thread on the front page about kids on a bus reading books. I've often seen on Reddit the belief that books (automatically) = "intelligent"/"thoughtful"/"creative"/[insert other positive descriptor here], but I think it's hogwash. (I'd like to point out that there are probably many examples of people *not* holding this view, but, from what I've seen, the vast majority of highly-upvoted content seems to follow this trend).
WHAT you read is infinitely more important than simply the act of reading, in exactly the same way that television is not all mindless dribble/smut/garbage.
I'd also add that the same goes for video games, movies, etc...
I think this quote from Groucho Marx exemplifies what I think is BS:
>I find television very educating. Every time somebody turns on the set, I go into the other room and read a book. | The written word has a very high information density. How long would it take a television program to explain something like calculus? And how much of it would simply be *reading from and showing things in a text*? For entertainment or easy concepts, a book has no serious advantage, but for learning complicated things, the information density inherent in a book makes it a far more efficient venue than that of other forms of media. As a result, books are perceived as more intellectual, because there are some forms of learning that the written word is the only reasonable solution for. | 23 | 30 |
I believe completing a degree in a STEM major requires more work than completing a degree in a non-STEM major. CMV. | I strongly believe that STEM majors are more difficult in both subject matter and the sheer amount of work one has to do than non-STEM majors. The only evidence I really have is anecdotal; that is, I take classes in STEM and non-STEM subjects, and the non-STEM classes are definitely much easier not only in how much effort I have to put in, but also the amount of hours I have to put in to get the same grade.
Those who do not believe STEM majors are more difficult than non-STEM majors: why do you believe what you believe? | This may have to do something with the fact that STEM knowledge is much more objective. If you're taking an exam in physics, you can't write the opposite of Newton's laws and then argue that it's correct. In some non-STEM fields you can pretty much do that and get a good grade if your reasoning is good enough. This makes it seem like you don't have to know anything, you just need to be able to build a decent argument. That's not really correct, because you have to know *a lot* to properly challenge something. | 30 | 21 |
CMV: there is no reason for Medicine and Dentistry to be separate fields | Dentistry should be a speciality of medicine and dentists should go through medical school. Dentists already need to have a wide range of knowledge about the body to understand the effect on teeth and other medical specialities need to have knowledge about teeth as they can be important indicators of eating disorders and tooth health had been proven to have a correlation with cardiovascular health.
I don't see why Dentistry needs to be an entirely different field when its relation to medicine is the same as other specialities relation to medicine | What is the gain vs what is the cost.
Dental school is already a specialized medical school. It is a specific curriculum designed to produce doctors who are experts in the mouth.
We have Podiatry - another specialized school for doctors of the foot. Optometrists who specialize on the eye. Both go to specialized schools not generic medical school.
All of these provide core elements of a traditional medical school but with a core focus on the specific specialty. It is not like a dentist is not getting the core from dental school.
The benefits are simple - restricted scope of practice and a higher level of expertise in that area. Why would you add 4-6 years on to the program to try to teach things that will never be used? | 12 | 31 |
How do a bunch of small noises combine to make a very loud noise? | So I was watching Game of Thrones last night. The soldiers started to slam their spears into the ground. One spear doesn't make much noise, but a lot of spears makes a lot of noise. Why is it that when a bunch of people do the same thing at the same time it suddenly seems like all of their noises are added to each other?
I guess in my head I have the thought that it would just be the same level of noise but coming from all around, this is obviously not true.
What's the science behind this?
I'm not exactly sure what to tag this as but I'll put physics because it seems to be the closest. | Read up on constructive/destructive interference in waves. Basically when sounds are the same frequency and phase the peaks lines up and the troughs line up and then add making the amplitude (volume) bigger. | 12 | 24 |
ELI5- Why are there unsolved mathematical equations? Who wrote them and how do they know if they are solvable or not? | So...you should note that mathematical problems and mathematical equations aren't inherently the same thing.
An equation is basically just two sets of algebraic quantities that have an equal/greater than/less than sign between them. Some of these equations are inherently not solvable because they have self-contradictory answers. For example, let's say you have the equation;
1/(x + 3) + 1/(x - 3) = 6/(x^2 - 9)
You can manipulate it (multiply both sides by "(x + 3)\*(x - 3)") to get the following;
x + 3 + x - 3 = 6
or;
2\*x = 6
or;
x = 3
But that doesn't actually work, because if you plug x = 3 back into the original equation one of the two terms on the left side of the equals sign gives you a 1/0 situation, which means that x = 3 is essentially not "allowed" to be an answer. Thus, the equation has no solution, making it unsolved.
For unsolved *problems*; those are basically just mathematical statements that we can't quite figure out if they're true or not. For example, there's the Collatz Conjecture; pick a number, and then perform the following operations;
1) If it's even, divide it by 2.
2) If it's odd, multiply it by 3 and add 1.
Then feed the resulting number back in, and again, and again. Doing this, you'll (probably) end up with a repeating sequence of 4, 2, 1, 4, 2, 1, etc. No matter what your starting number is, you always seem to end up in this pattern because *eventually* you wind up with some number 2^N and the whole thing collapses.
The problem is that we can't figure out how to prove that it's explicitly true for all numbers; we can only observe that it hasn't been disproven yet, which is not good enough for mathematics. Thus, the problem is unsolved. | 113 | 101 |
|
ELI5: why is it that some metals like zinc and iron are essential for our bodies while other metals like lead and Mercury are toxic? | We have enzymes in our body called metalloenzymes that contain metals to catalyze chemical reactions or maintain the enzyme's structure. These essential metals include iron, zinc, calcium, magnesium, copper, cobalt and a few others.
Most metalloenzymes work only with their original metal in it. For instance if you replace the zinc atom in the enzyme *Carbonic anhydrase* with another metal, it can't function anymore. Some of the toxic metals you mentioned are similar in e.g. size or charge to these native metals, which means they 'fit' in the same spaces. So when lead or mercury enters a cell, it can replace the 'natural' metals inside the enzyme. (In many cases it even binds more strongly to the enzym than the original metal, making it harder to get out of there as well.) | 540 | 1,070 |
|
CMV: Actual effort and ability is rarely noticed. Perceived effort and ability gets all the attention, and it's killing productivity | Person A and B are assigned a task at some company. Person A gives 100 percent effort to the task. Person B divided his time between the task and acting above his pay grade. The task gets done, and supervisors see two things: it got done, and Person B. In reality, Person A is capable of, and does regularly, complete the task by himself, and doesn't get recognized.
It has been said that you should perform for the job you want, not the one you have. If everyone did that instead of being dedicated to the mission, things would take much longer than necessary, or wouldn't get done at all.
If I can see when someone is doing a good job, or is struggling, then anyone with a reasonable amount of situational awareness should too. Why should one have to 'sell' himself? It takes away from the mission.
Workers who are actually good have to pick up the slack for these overreachers, which decreases their own morale. They may even leave the company over it. Losing good workers makes the situation even worse. Care to change my view? | Any attempt at checking for effort and ability will only yield perceived effort and ability by definition. It would be nice if we could tell better, but that's always true no matter how well we can tell. There's only two options: reward people for perceived effort and ability or not reward them for perceived effort and ability. Do you think it would be better if pay and promotions were decided through some other method, like seniority or dice rolls? | 18 | 98 |
ELI5:Why does ~x = -x - 1? | I've always been confused about why the bitwise negation `~` of any number `x` equals `-x - 1`.
Should the bitwise negation flip each bit from 1 to 0 and vice versa?
For example, `~10 = -11`, but the binary representation of `10` is `1010` and the binary representation of `-11` is `-1011`?
How come that works? | In binary math, for most systems, we use what is called Two's complement. It is a way to eliminate the possibility of a positive and negative 0.
The highest bit (the left-most bit in a binary sequence) is the sign bit. If it is 1, it is a negative number. If it is 0, it is either 0 or a positive number.
If you were to flip 0, and we didn't do this, you'd end up with all 1s. Instead of having to check between 2 different versions of 0 (one 'negative' and one 'positive'), it is more efficient to just check against one version. This gives an extra integer to use and still works out to correct answers when using binary math (addition and subtraction) without requiring conversion. | 10 | 24 |
ELI5 why we can secure banking/investment accts online but we can't secure voting | seems to me like if we can trust billions of dollars to banking websites and stock trading websites, then we should be able to create a trustworthy secure electronic voting method
| The requirements are different.
Most importantly, banking information needs to be tied to the person making the transaction. If any inconsistencies come up they need to be able to make sure they have enough identification information to trace the transactions back to the person who made them.
This is exactly the opposite in voting. Voting has to be anonymous. Having anonymous voting but still being able to trace the inconsistencies back is a trickier problem. It's not impossible tho.
The real big issue is that an election screwing up and a country having a tyrant running it who is willing to fix an election to win is far, far worse than any loss of money a bank might suffer. Electronic elections software has way more riding on it than banking software. | 37 | 95 |
ELI5 how can weed and crabgrass killer target said specific plants without damaging common types of grass? | Plants have certain processes that keep them alive and help them grow, and different types of plants can have different processes. Weed killers and herbicides can be made to target processes that happen in weeds and not in common grass.
Edit: not all weed killers are like this. They can also be non specific and kind of just kill everything. If you're buying just be careful on what brand you buy and do some research before you destroy your lawn | 10 | 18 |
|
ELI5: How do producers prevent child actors in horror movies from getting extremely scared? | First, they take the time to explain things to them, and prepare them, and they have their parents/guardians present. And kids who can't handle it probably don't survive long in the industry.
Second, when filming a movie it's not nearly as scary as the finished product. Think of it with out the jump-editing, without the scary music, without the sharp, jarring angles. If anything, the kids probably get bored.
On a related side-note: When filming *Maleficent*, Angelina Jolie had to use her own child for some scenes since the other children were afraid of her. Which relates to being able to find the right kid for the job. | 285 | 263 |
|
What coding languages should I use to create this type of web & mobile app? | Hello! I was hoping I could get some direction in which coding languages to use for an upcoming project of mine. I'll try to give some background of what I am trying to accomplish. First off, I want to start developing this application for web, but eventually want to offer a mobile app on both android and apple phones. To preface, I have little experience coding back end applications, but I have over a year to learn / development what I need. I do have some some ok experience in front end, UI/UX development, and PHP so I am familiar with how code works.
The idea of this application is very similar to how crafting works in video games. Essentially the user will create a list of materials that they own, and the app will tell the user what they can make with the materials they have on hand. Eventually it will get more complex by recommending adding additional materials to show what else they can make. For example, it may say... if you add 1 of "x" material you will be able to craft all of this! So I guess there would be two main databases: the inventory of the user, and a list of crafting recipes.
So, the question is really what coding languages should I start to learn/develop this type of application with? I want to make sure its future proof when I start adding more features as I become more experienced. Are there any special front end languages I should take advantage of, as I generally just code in html/css and don't use anything special for website development? What type of database should I use? Whats the best language for the backend; python since I am new to all of this?
Let me know if there are any questions you need answered to help with giving advice. Thank you in advance! | The easiest approach is to create a responsive web app, with a hi framework like Bootstrap or perhaps a more mobile specific one like Ionic.
You'll need to know HTML, JavaScript, (A JavaScript framework like Angular, Ready or Vue, these all work in Ionic), for the backend nodejS which is again JavaScript. | 10 | 18 |
[ELI5] What does it mean to be "grounded" against electricity, and why does it keep you safe? | There is two facts that we have to establish here first in terms of safety around electricity.
1. Electricity hurts you when it flows through you.
2. Electricity prefers to flow through path with least resistance. Like water, if one pipe is small and the other is big, water would flow more through the bigger pipe. In other words, electricity is lazy.
Now, according to fact 1, if there is little to no electricity flows through you, then you're fine.
According to fact 2, electricity doesn't flow if you have significantly higher resistance than other path.
So, usually, what we do is:
1. We provide a superbly easy way for "rogue" electricity to flow. This is usually accomplished by having the machine "grounded" (having an almost direct connection to literal ground)
2. We make ourselves as resistant as possible, via rubber-gloves and shoes, usually. | 63 | 61 |
|
ELI5: When exercising, does the amount of effort determine calories burned or the actual work being done? | Will an athlete who runs for an hour at moderate pace and is not tired at the end burn more calories than an out of shape person who runs for an hour a way shorter distance but is exhausted at the end?
Assuming both have the same weight and such
What I want to know basically is if your body gets stronger will it need less energy to perform the same amount of work? | In general no, it requires a set amount of energy (calories) to do the same amount of work. In fact, work and energy as physical quantities have the same measurement unit (it’s Joule). However, it is possible that training will make your body more efficient at doing work, so there may be less energy wasted (like on needless movements, or panting etc.) and thus less energy spent overall. But being exhausted does not necessarily mean you’ve done more work. | 1,172 | 2,454 |
ELI5: how can electrons just be ok on their own and fly around? | Where do these spare electrons come from? Do they come from atoms? If yes, how are the atoms able to just lose their electrons and it be ok? I mean like in the Maltese Cross experiment you're essentially "shooting electrons" but I just don't get where they come from. Thanks in advance :) | In certain substances, particularly metals, some of the electrons become community property, freely shared between atoms. These atoms are free to flow through the metal and are the reason metals tend to be good at conducting electricity.
These electrons can be stripped away from the metal to perform the experiments you describe. The metal will have a slight positive charge and tend to grab electrons from the environment. The electrons will eventually join atoms to form negative ions, and those ions will be eager to give up their electrons. Over time, extra electrons will be lost and missing ones gain, and the overall system will reach equilibrium.
| 15 | 15 |
What happens to an ant colony if its Queen is artificially removed? | I recently watched BBC's ["Planet Ant- Life Inside The Colony"] (http://www.youtube.com/watch?v=8n0SkIGARuo) and after watching it I wondered what happens to the biological machine (the ant colony) after its Queen is gone.
* Is there a second in command who will grow to the size of a Queen via chemicals?
* Do they spread out in search of a new Queen to serve?
or.. * Does the colony just die out due to the lack of a Queen?
| It depends on the species of ant. Harvester ants (large, red and slow) from Arizona will never raise a new queen, so the colony will die within about two years (which is the average lifespan of a worker). One quheen per colony. For reference, their queen lives for 20-25 years.
Argentine ants (small, black, invasive species) have many queens, and make more as they go. They are robust to losing a few.
Source: several years of undergraduate research on ants. | 1,623 | 2,015 |
If I had a pressure cooker that could raise the boiling point of water above 300 degrees F, could I fry food in water? | Caramelization of sugars and the maillard reaction, responsible for the browning and crisping of food, is associated with temperatures in excess of ~300 degrees F. Since water at atmospheric pressure boils at ~212 degrees, caramelization and the maillard reaction don't occur and the food gets neither brown nor crispy.
But what if I had a pressure cooker that could raise the boiling point of water above the requisite temperature? Would it get brown and crispy, effectively frying it? Or would something else (likely unpleasant) happen, such as the food getting brown but waterlogged/soggy? | The Maillard reactions are affected by moisture content, so using water as a cooking medium, regardless of temperature, will prevent them from occurring. And since the pressure you're positing would prevent the water in the food from escaping as steam, you won't get a crispy texture either. | 616 | 829 |
CMV: Adding /s to a statement kills the joke. Always. | A sarcastic joke or remark should stand on its own merit and no additional indicator should be provided to emphasize or clarify that there is humour. In fact, the doubt that the statement creates, the "is this person serious?" plays a major part in creating a humorous payout.
Poe's Law may be invoked in defense to the /s but again, a quality sarcastic statement will take Poe's Law into account and use it to its advantage! The danger is that it may sometimes lead to failed zingers when the audience takes the statement as non-sarcastic. If this happens, then so be it. Safe, fail-proof humour is worthless. The value of comedy lays in the inherent risk to flop.
It is a travesty that we as a society have grown to accept this diluted brand of comedy as standard or even acceptable.
I've also seen the /s being used in non-comedic context which I find equally offensive. Often in political subs, you will see people attempt to belittle or mock an opposing point of view by making grotesque statements followed by /s. Once again, adding the /s only creates an obvious "please clap now at my cleverness" which completely kills any pertinence of the words.
I understand the /s originated from the loss of tone and visual cues from face-to-face interactions but it's been turned into an instant-funny or instant-clever writing shortcut and it is an embarrassment to the written language.
Anyone who uses /s is automatically not funny or clever. | In face-to-face conversation there are multiple factors that mark sarcasm, body language, tone, pitch, pace.
Without these markers it would often be impossible to tell if you are joking or if you are completely serious.
On the Internet, these contextual clues are missing. All you see is a black text with no indication as to tone whatsoever.
A lot of times without /s, many people would think you are being completely serious. Just pick your favorite joke and try telling to people in drone monotone. You will see why it does not work. | 23 | 23 |
What should I read to learn about Islamic Philosophy? | I own two books on the topic, The Sufi Path of Knowledge and The Teleological Ethics of Fakhr al-Din al-Razi, and really want to dig into them, but I’m afraid that I’m not prepared for the reading. I’ve read the Quran and Plato’s the Republic, but other than some Camus and Jean Paul-Sartre I’ve no real experience in philosophy. I’m mainly interested in metaphysics and ethics, and I think the Islamic tradition is the right place to start for me. Any advice on what other readings I should do would be helpful, thanks!
Edit: Sorry for not responding immediately to all your great responses. I wrote this post down right before going to sleep. I truly do appreciate your help, you are so amazing and courteous. | There is Peter adamsons Philosophy without gaps which goes through Islamic Philisophers and their ideas, there are also books by syed hossein nasr which are decent.
I would recommend reading the Philosophers by keeping in mind the historical and political narrative, sometimes they were responding to the greeks as well
Maybe start with al kindi, al farabi, ghazali, averroes and avicenna and then there is the sufis as well, most prominent being ibn al arabi
And you might find brethren of purity interesting. | 15 | 32 |
ELI5: Why don't optometrists and dentists work in hospitals? | Why don't we just centralize all medical needs? | Some hospitals do have doctors that focus on teeth and optics.
But most of the time these are lumped in with bone and nervous system specialists.
The simple fact is that they don't need them there. People waiting for a dentist don't want to have to navigate through a hospital, and hospitals don't want to deal with everyday stuff, hence why few hospitals have actual clinics in them, most of the time are just walk-in clinics. | 20 | 58 |
ELI5: why are (public) school breakfast/lunches (k-12) typically not freshly cooked and not very healthy in america? | Would it really cost so much to provide freshly cooked lunches/breakfast that it is not possible to do so?
Edit: i know not *all* public schools in the us have crappy food (hence the word typically). A good chunk of them do, though i know that there are districts (typically in more affluent areas) for which this is not an issue. | * Ease of preparation - most school districts have many schools, and coordinating daily deliveries of multiple fresh ingredients to all of them is tough. They focus their energy on classroom activities.
* Cost.
* Inertia - it's a bunch of work to change something like that, and that means someone has to stop what they are working on and manage that change process. If it means bringing in a private company, the current food services people lose their jobs.
* When schools sell healthy and not healthy food side-by-side, kids almost always buy the not-healthy.
Edit: formatting bullet points. | 75 | 128 |
[The Matrix] if two people plugged into the matrix conceive a baby... how is the baby born in the real world? if the two people never even touched? | A conception effort that achieves success trips a program flag that selects a prospective suspended zygote of the right phenotype and genotype from the baby farm. The selected zygote is then put through its growth cycle, to be eventually plugged in to the Matrix proper once it has matured to usefulness. This process similarly triggers a procedure in the Matrix proper that links the mother's experience to the growth cycle of the child, simulating a pregnancy from beginning to end. | 82 | 57 |
|
[Warhammer 40k] How come Khorne is so popular? | Look, I know that in the grim darkness of the far future there is only war, but there are quadrillions of beings in the galaxy that are hardly ever exposed to war.
Suppose I'm Billy the Farmer from an agriworld who decides to join a chaos cult. What does each chaos god have to offer me? Eternal excess and pleasure. Nihilistic comfort and acceptance. Forbidden knowledge and magic powers. And...being really angry?
I get why Space Marines and suchlike would fall to Khorne, but it seems to me that an average person who falls to chaos would be much more likely to seek personal comfort offered by the likes of Slaanesh or Nurgle, than roid rage. Most people aren't really inclined to violence and murder.
So how come Khorne is one of the most powerful and influential chaos gods, if not the most powerful? For every Space Marine or hardass IG veteran who can't live without the thrill of violence, there are thousands of Imperial civilians who would rather do cocaine or wallow in filth than have to go fight someone. | First of all, you have to remember the lens through which we are looking at this universe. Our focus is primarily on the armed forces of the various factions - and, in the case of Khorne, the armed forces of the Imperium of Man (Eldar are too regimented, Necrons too soulless, Tau too insignificant, and Orks too orky).
Human military forces tend towards certain ideals - honour, courage, camaraderie. Khorne offers all of these, at least at first (they rapidly spiral into arrogance, anger, and elitism). This makes him very attractive to those of a martial bent.
This means that Khorne's followers are going to be over-represented on the battlefield. Soldiers who are going to fall to Chaos are most likely to fall to Khorne; people who fall to Khorne are most likely to become soldiers.
You'll find few Khorne worshippers in the pleasure-houses or gambling dens of a peaceful paradise world, or among the schemers and backstabbers of a corrupt court, or among the farmers and physicians who struggle to sustain life on a halfway-barren planet. You'll find a few, of course, because there is courage and honour and fury and pride to be found everywhere that humanity has put down roots, just as you will find worshippers of Slaanesh and Tzeentch and Nurgle on the battlefield.
The second thing to consider is simply a matter of visibility. How do you spot the Slaanesh worshippers? They're the guys having an orgy in a secret club in a back alley. How do you spot the Tzeentch cultists? You don't, you just find their fall guys who the actual Tzeentchians (claim they) wanted you to catch anyway. How do you spot the followers of Nurgle? They're working behind the scenes in healthcare, sanitation, and food preparation.
Okay, and you know how you spot the servants of Khorne? They're the ones running at you screaming incoherently and waving an axe.
tl;dr Khorne seems more popular because he's naturally over-represented on the battlefield, and off the battlefield his followers are extremely easy to spot. Billy the Farmer probably isn't going to follow him, but there’s plenty of people who will. | 46 | 28 |
CMV: Elders don't deserve respect just for being old | Why should I respect someone for being old?
I get that as a majority senior citizens are probably wiser than those younger due to their experience in life, but there’s no way that’s true in every case. When I meet someone, it doesn’t matter their age / gender / appearance, I judge and respect them based off how they act. If Asians have an average higher GPA than white people, do we treat them with more respect because they must be smarter?
Also, wouldn’t giving an old person extra respect for no reason other than age be ageist? | the reason that we do things like designate certain seats or parking spots for the elderly, disabled, pregnant, is that because one important marker of a society is how well it treats the infirm and vulnerable. same with entitlement programs like medicare and social security. it's not saying *they're* inherently more important. it's saying that our society is so safe and well administered that we can afford to take care of people that can't care for themselves. also the reason that people freak out more when small children get shot in school shootings | 101 | 164 |
CMV: There is no justifiable reason for organizations to offer internships that are unpaid | Unpaid internships are labor theft. There is no reason a person contributing to an organization should not be compensated for their work (and no, experience does not count as compensation). The idea of an unpaid internship is elitist and discounts tons of qualified individuals who may not have the means resources to work for free. I feel this further contributes to the diversity problems of many organizations and industrires as it sets those who can afford to go months without pay ahead of those who cannot. Organizations that cannot afford or refuse to pay interns should not offer internships. | >There is no reason a person contributing to an organization should not be compensated for their work
For an unpaid internship to be legal, the intern needs to be the "primary beneficiary" of the arrangement. There is a 7-point test to determine this:
>1.The extent to which the intern and the employer clearly understand that there is no expectation of compensation. Any promise of compensation, express or implied, suggests that the intern is an employee—and vice versa.
>
>2. The extent to which the internship provides training that would be similar to that which would be given in an educational environment, including the clinical and other hands-on training provided by educational institutions.
>
>3. The extent to which the internship is tied to the intern’s formal education program by integrated coursework or the receipt of academic credit.
>
>4. The extent to which the internship accommodates the intern’s academic commitments by corresponding to the academic calendar.
>
>5. The extent to which the internship’s duration is limited to the period in which the internship provides the intern with beneficial learning.
>
>6. The extent to which the intern’s work complements, rather than displaces, the work of paid employees while providing significant educational benefits to the intern.
>
>7. The extent to which the intern and the employer understand that the internship is conducted without entitlement to a paid job at the conclusion of the internship. | 103 | 495 |
The fovea is so small compared to the size of the visual field, so why does the world not appear to be of terribly low fidelity? | By fidelity I mean blurred and generally degraded. | To add to what /u/monory said, you don't *experience* the world in low resolution because of generally speaking if you are actually paying attention to an object or landscape - in other words actively trying to process, understand and commit it to memory - you will point your fovea at it.
Additionally, ALL of your senses are shaped by previous experience. It's called top down processing and it is basically your brain filling in gaps in sensory information. For example, generally all of the grass you've ever seen is a certain shade of green. Therefore, even though your peripheral vision lacks detail and color, your brain will experience that *whole* meadow as green, not just the part landing on your fovea.
That's just one example of many that keeps you from being totally disoriented by objects outside of where your eyes are focused. | 22 | 80 |
[Harry Potter] Are there such things as wizarding universities? | As in, if students would like to further their education, is there like a degree scheme for wizards or do they just have to get jobs/learn a trade etc? | It appears that on-the-job training and self-study are the rule for Hogwarts graduates seeking to advance. The top students that we know of from Potter's circle of friends didn't ever speak of university training, they talked about going directly into their field of interest. | 35 | 48 |
eli5, what happens to the dead bodies in a battlefield | Humans war against each other all the time, and throughout history hundreds of millions of people have died on the battlefield.
This begs the question, what happens to the bodies?
Like on the beaches of Normandy, thousands of people died. But the beaches, to my knowledge, aren't filled with dead bones and stuff.
So where did they go? Is there a secret service that collects bodies? | There are special units in militaries whose job it is to collect/clear bodies.
So best case scenario, that unit comes through and properly handled your body.
Middling case scenario is that unit doesn’t find you, and whatever locals attempt to give you a proper burial.
Lower case scenario is you’re just tossed in a hole and covered up like a mass grave.
Worst case scenario is no one ever finds you and your body is left to rot, decay, and he picked apart by scavengers. | 59 | 19 |
Can flammable liquids/gases just "combust" in high temperature environments or do they require a spark or some sort of ignition/catalyst? | We touched on the combustion of organic molecules in my org chem class and I was just curious if a flammable substance is placed in a controlled environment and the temperature increases, will it eventually just ignite?
What would happen to initiate this on the molecular level (like is there a mechanism)? | A diesel engine operates by this principle. A fuel-air mixture is compressed until its temperature and pressure become great enough for it to ignite. What happens on a molecular level is that in order for any reaction to proceed, there is a certain energy barrier that must be overcome, and once the temperature is high enough, the molecules have enough kinetic energy to overcome that barrier. | 11 | 23 |
ELI5: Where do rich people keep their money? | If I wanted to rob a poor person I would have to go their house and steal their stuff, because all their money is used up to buy "stuff." But if I wanted to rob say, Alec Baldwin...where is Alec Baldwin's money? | Banks, stocks, bonds, real estate, other "stuff".
Rich people store most of their money in investments, earning them more money so they can stay rich. Don't get me wrong, Mr. Baldwin probably has more than enough cash in his bank account for anything he could want, but for the most part you're not going to hit a rich guys money by robbing him physically. You'll need to hit him electronically too. | 21 | 15 |
How do I understand Discrete Mathematics? | Hello, I'm currently studying Software Engineering, and would like to hear some advice on what are the best methods / ways to learn and understand Discrete Mathematics?
I genuenly dislike math, and am abit scared of the whole subject. | If you're struggling with it, read the relevant textbook chapters before class, then attend lectures and ask questions, and start your homework assignments early so that you have time to go to extra help sessions.
If you're stuck, textbook practice problems are a great place to look, since they build up from simple to complicated.
If you spend more time studying (and just thinking about the material in general), you'll understand it better. If you understand it better, you'll enjoy it more. Or at least, hate it less and feel less afraid of it. | 13 | 20 |
ELI5: How do airplane standby passengers work? | I don’t understand how someone gets put on standby. Is there some sort of standby ticket? If so, how.. and do people really go through all the hassle of going to an airport while having a possibility of going home? | It's also worth noting that some airlines offer same-day-standby changes to elite customers (and/or charge for it).
This might be attractive for someone who booked a late flight, but then later realizes they don't need to be at that origin city any longer that day. The airline notes there's one or more earlier flights that same day that would get them home earlier, but they're already sold out. The traveler might as well hang out at the airport with the chance of getting to go home earlier instead of the alternative of spending all day without anything productive to do | 92 | 94 |
ELi5: what is that horrible painful massive 'lump' in your chest when you drink or eat something too fast? | Food and fluids get transported through your esophagus. Where the esophagus connnects to the stomach, a) it has to pass through an ligamentous opening in the diaphragm, which is a rather narrow passage and b) there is a sphincter muscle that is usually contracted to prevent stomach acid to flow back into the esophagus. When you swallow your food too quickly, the sphincter may need a few extra seconds to relax and let the food into the stomach. In these - usually - seconds, the food is stuck in the esophagus, which is unfortunately located right behind the heart. And your heart really dislikes something pressing against it, therefore causing that uncomfortable feeling. | 37 | 74 |
|
Eli5 If bug killer can kill insects, how is it safe to spray all over your house and not be harmful to humans? | In general, modern pesticides are designed to target specific things that the insect has and mammals (like humans) don’t. Since we are pretty distant from insects genetically, there are numerous proteins in insects that either do not exist in, or are substantially different from ones, in humans. | 151 | 155 |
|
Is an O(sqrt(n)) solution really that bad? | So I am researching elliptic curve cryptography and I keep getting terribly confused about what I'm reading. Let me give some very basic background:
BACKGROUND: Many traditional cryptosystems are built so that to "break" the system, one has to be able to solve a problem called the "Discrete Logarithm Problem" Conversely, to break an ECC system, one has to be able to solve the "Elliptic Curve Discrete Logarithm Problem." One of the reasons ECC is useful, according to every book I read, is because there are subexponential algorithms which solve the regular Discrete Logarithm Problem, but the best current algorithm to solve the ECDLP runs in O(sqrt(n)) - this is supposedly indicating the ECC system is harder to break.
Every single book I read seems to say this but this is really confusing me. What's so bad about an O(sqrt(n)) time solution? I guess I'm confused because back in my original programming class, a lot of the search algorithms and just regular algorithms we learned would be O(n^2). I remember how an O(n) linear solution always seemed like a great solution. Isn't O(sqrt(n)) even better? Also, how is O(sqrt(n)) NOT a subexponential solution?
Example quote from book: Elliptic Curves in Cryptography by Blake, p.80: (talking about algorithms to "break" ECC systems): "The last two attacks listed are quite general but have complexities on the order of sqrt(n). They become infeasible when the curve order is sufficiently large."
another quote:
"The main reason why (ECC) is "more trusted".... is because (the discrete logarithm problem)... can be solved in subexponential time with index calculus algorithms. Until recently... the time required to solve (an ECC system) was believed to be exponential in the size of the parameters." | The search algorithms are parameterized in terms of input length. The n is very likely a number and not the size of a number. The input length is then log(n). So if an algorithm takes O(sqrt(n)) time it will take O(2^{k/2}) if k is the bit length of n. | 11 | 16 |
Is stoicism and existentialism a view that can coexist? | So I tend to follow stoicism as a personal philosophy but see existentialism a meta- philosophy that makes sense to me. I try to live my life by stoic virtues but also tend to view life as having no explicit or implicit meaning. Are these two views able to live in the same realm or are there some of these philosophies that are at odds with each other and thus, me holding hypocritical views? | I’m no expert in either, but historically, the Stoics seemed to have been strong believers in determinism and fate, while existentialists like Kierkegaard and Sartre emphasized freedom as an essential component of humanity. Wonder if that leads to a conflict? | 52 | 65 |
ELI5: When searching for jobs online, I almost never see an amount (whether hourly or salaried) of how much a company will pay an individual who actually gets the job. Why is that so? | they want to get away with paying the minimum amount they can, so they usually ask you for your past salary info and make a slightly better or similar offer.
they don't want to start the salary listing higher than they need to. | 21 | 24 |
|
CMV: Girls-only math and science competitions are counter-productive and do not help to encourage more girls into these fields | Currently math and science tend to be much more male\-dominated than other fields, and this seems to be the case in math/science competitions as well. Competitions like the International Mathematical Olympiad \(IMO\) are usually disproportionately male dominated to the extent that one or two girls on a country's team is enough to make the news. To encourage more girls to enter competitions like this, and to encourage interest in STEM, there are some competitions like the EGMO \(European Girls' Mathematical Olympiad\) that are open only to girls.
I find this counter\-productive because I don't see the reason why creating a competition only for girls will actually help encourage them into math and science. Separating by gender can give people the incorrect impression that girls are less able than boys in these fields and therefore require a separate competition to get anywhere at all.
The only reason I can think of for why a separate competition needs to be created for different genders is when significant physical differences would make a combined competition unfair \(which is why physical sports are separated by gender\) but in academic fields like math and science I don't see any biological reason why someone with XX chromosomes should be predisposed to be worse in STEM.
In addition, since the population is close to half and half male and female, a competition limited to one gender would probably mean less people take part \- so the fact that there are fewer people in the female only competition will mean that standards are lower overall, *just because there are fewer people in the competition.*
\(It's like if you take the fastest person in a large city and a small village, the fastest person from the city is statistically more likely to be faster than the village person because there are more people in the city so the probability is higher\).
This may mean that the girls only competition may be perceived as second\-rate or at a lower standard and wrongly stigmatise girls as being less able in math even though it isn't the case, which is counter\-productive to the original intention. | It can be very intimidating to go into an environment and have an uncontrollable trait (race, gender, etc.) that sets you apart from the vast majority of the other people in that environment. Ideally, in 100+ years, we won't need women only competitions in academics, but now it gives women an environment where they can foster their love of science without dealing with the intimidation that comes from being different from almost everyone else they're competing with. And after they gain the confidence from competing against other women and do well there, they may have better confidence when it comes to competing against anybody else. It has nothing to do with biological reasons and everything to do with social ones. | 807 | 1,964 |
Can someone explain why most published research findings are presumed false? | In his now classical paper, Why Most Research Findings Are False, Ioannidis makes a pretty strong case for why we should be more skeptical about published research. He lists six reasons for why any given research finding can be false, and most are convincing.
But there is one reason I can't wrap my head around, which is: "The greater the number of tested relationships in a scientific field, the less likely the research findings are to be true." He gives an example of why this is true, where if you test to see which out of a pre-selected 100 000 gene polymorphisms are associated with schizophrenia, you'd probably only find 10 significant ones. Fair enough. But then he says that this is equal to saying that the pre-test probability of finding an effect is 10 / 100 000, and that because of this, the probability of your finding actually being a true effect (aka positive predictive value, PPV) is only slightly higher than 10 / 100 000 = 0.0001. He seems to conclude that research fields that test a massive amount of relationships are either very unreliable or even not worth doing.
But if this is true, how would you ever be able to for instance test genes associated with mental illness in a satisfactory manner? If you base the probability of your finding being true (PPV) on your pre-test probability of finding an effect, how on earth can you demonstrate that your 10 genes out of 100 000 are actually significant and worth further study? How is any genetics research taken seriously, if what he says is true?
I've read through the paper twice now, and while I'm by no means an expert in statistics, I thought I was well-versed enough to make sense out of this. Did I understand the paper correctly? Perhaps I've missed a few important details, or haven't quite grasped the big picture. Can anyone clarify?
Link to paper: [https://journals.plos.org/plosmedicine/article%3Fid%3D10.1371/journal.pmed.0020124](https://journals.plos.org/plosmedicine/article%3Fid%3D10.1371/journal.pmed.0020124) | It seems to me the problem he is describing is one of fishing for an effect rather than hypothesizing an effect and then testing for it. If you screen tens of thousands of genes for an effect, your test will at some rate return an incorrect positive. But, if you have a hypothesis that a specific gene has an effect, this error rate is likely to be considerably less. We need to fish less and properly test more. What we call testing isn’t. | 32 | 29 |
ELI5: How does a human being stay in a coma for many (like 10 or 20) years, and what wakes them up? | While you are in a coma, assuming that you are being kept alive and your brain has some function, your brain devotes a grear amount of enery to repairing itself. This process is difficult and energy intensive so some times it takes many years for the brain to repair itself to a level were you can remain conscious. | 114 | 229 |
|
Why is 7nm considered the limit of Moore's law? | I understand that around 7nm silicon can no longer be used, but I am unsure why. I have seen that using graphite can lower the limit to 5nm, but again unsure why. | Commercial integrated circuits today are made using projection methods. This can be grossly simplified as follows.
The wafer is coated with photoresist. A stencil of the circuit is projected onto the wafer; where the light hits the photoresist, it gets developed just like an old analog camera. This process is fundamentally limited by the wavelength of light. Because of diffraction, you can't really image features smaller than the wavelength of the light you are shining through the stencil. Most systems use deep UV light today to get the smallest wavelengths and smallest features. They also play tricks with double exposures and complicated stencils that are specially shaped to counteract the diffraction. But again, you can only get so small with projection.
After this projection, you are left with a print of the stencil on the wafer and can remove or add or dope patterns and form a chip architecture. This process is repeated dozens of times to stack up the full circuit.
Right now, we are pushing up against the limits of what is possible with UV light. It is difficult to just further shrink the wavelength because you start pushing up into x-rays which just pass through most things and cant be focused like UV.
Of course, there is a whole zoo of other specialized methods that have been demonstrated in laboratory settings, but they do not work well for large scale production. For example, using something similar to an electron microscope to scan the pattern into the wafer can give very fine features but is very slow since it must move line by line rather then an entire exposure at once. | 62 | 84 |
CMV: The outcome of a crime should not matter in sentencing | First of all, I realise there are differences between countries and jurisdictions so I am not bound to a specific one here.
I believe that only the intent combined with previous relevant convictions and circumstances should be taken into account and not the actual outcome of a crime. In addition, I am in favour of sentencing based on rehabilitation vs punishment. I will give two examples:
1) Bob points a loaded gun at Tim and asks for money. Tim refuses to give him anything. Bob points at Tim's head and pulls the trigger but the gun fails to fire and Tim is unharmed.
The above example would most likely result in an attempted murder conviction and depending on jurisdiction might be given a shorter sentence than if the gun had fired. I cannot see why the fact that Tim survived by accident changes the fact that Bob decided to bring a loaded gun and did not hesitate to use it. In this situation Bob is already a murderer as far as I'm concerned and should be sentenced accordingly and rehabilitated because he is currently a threat to society.
2) A father witnesses the murder of his daughter and the killer runs. He picks up a knife, chases after him and kills him. The father has had no previous convictions.
This might result in voluntary manslaughter or even murder. Taking into account that the father is known not to be violent, what would be the point of a sentence that takes into account the killer's loss of life? How would he be "rehabilitated"? What from?
What do you think?
_____
> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | The justice system has a strong tradition of protecting the presumption of innocense. Intent is very hard to derive, to prove that someone would not just plan a crime but actually go through with it.
Innocent until proven guilty means that as an ideal we need to prove someone would actually do the deed. If say the gun misfired how do we know they didn't purposely aim away from their head, or didn't misload the gun?
So to protect the innocent we decide based on outcome, not intent, as if we decided based on intent many innocent people would be convicted and imprisoned.
As another point, we want criminals to have an incentive to stop. If someone tries to shoot you in the head, and it fails, they could then try to bash in your head, or fire again. Do you really want that criminal to now know that the consequences for them will be the same regardless of what they do? Our prime goal is to stop violent crimes, not to punish the guilty.
As a third point, we want to punish competent killers and such more than incompetent attempted killers. Competent killers are a greater danger to society. | 20 | 23 |
ELI5: Speed causes time dilation. Mass causes time dilation. What is the link between speed and mass which means that they both cause the same phenomenon? | I hope the title makes sense. | To try to make this very simple, space and time are both components of a single thing called, very logically, spacetime. Spacetime is a coordinate system consisting of three spatial directions and one temporal direction. Time dilation is a result of the way things move through spacetime. Both speed and gravity are related to the way things move through spacetime, which is why they both cause time dilation.
For speed, again, in a very simplified way, you can conceive of everything moving at a combined “velocity” of c (“the speed of light”) through spacetime. Thus the faster you are traveling through space, the slower you are traveling through time, and vice versa.
Gravity, by contrast, is the warping of spacetime by mass/energy. Just as it warps the path that objects take when traveling through space, this warping also affects the path they travel through time.
The mechanics are different, and the end result is also different (time dilation due to velocity in special relativity is reciprocal. Gravitational time dilation in general relativity is not), but the common thread is the interaction with spacetime. | 67 | 95 |
ELI5: Since we're aware of the elements required to create water (H2O), are we able to do so? Are the elements scarce/abundant? If not/so, why don't we just create water and supply it to places in need? | This might be a dumb question, but it seems so simple...which might be exactly why it isn't... | The elements of H2O are Hydrogen and Oxygen, two gasses. They're not all that common in their raw form because they react with things, so they're normally in compounds, like water. You can get hold of pure hydrogen and pure oxygen quite easily though - the easiest way to do it is to use electrolysis to split water. Water is extremely common compared to almost anything else.
It takes a lot of energy to split water into hydrogen and oxygen, and when you combine them back again to form water, you get a lot of energy out. You can power a rocket with it.
None of this is more practical than just piping water to somewhere that needs it.
Edit: BTW if you think "there are no stupid questions", have a read of some of the lower-rated replies to this post. | 1,157 | 1,207 |
ELI5: How does burned food stick to glass? What's it holding onto? | The proteins and carbohydrates in food are glue.
Old-fashioned methods of making glue used the long protein molecules in animal products. Long molecules help the glue stick to itself and the surfaces. Modern glue contents don't differ much from the old fashioned contents.
When you cook food too well, you evaporate the water so the food glue hardens. The chemical reaction for glue to bind to a surface also increases with temperature. This caused the food to bind to metal and glass surfaces.
Glassware in particular can absorb and hold more heat than it's metal equivalents (due to it's greater thickness). This means it can transfer a lot more heat and burn/glue food to it easier than metal.
Nonstick surfaces do not react to form bonds with the food glue. That's what prevents the sticking. | 373 | 558 |
|
Is there a scientific basis for the concept of "fresh air"? | What is the difference between "fresh air" and "stale air". Is there more oxygen? Less CO2? Fresh air seems to have a fairly profound physiological effect on some people, elevating mood, reducing nausea, etc. Is this merely a placebo effect at work or is there really something about "fresh" air that rejuvenates a person? | Air is comprised of nitrogen, oxygen, argon, water vapour, carbon dioxide and minute traces of other gases.
Air entrapped within a home will tend to equalize with the outside air, but does so slowly. Simply as a result of your presence, air composition in your vicinity changes. Respiration produces carbon dioxide (increasing its volume fraction) and water vapour (increasing humidity). Your skin cells slough off to create airborne dust (particulate matter). In addition to the effects of your body, objects within your home oxidize (rust) consuming oxygen from the air in the immediate vicinity. The particulate matter load is added to by small particles breaking off from solid objects as you move them around. Dust mites and their waste add to the airborne dust load. Outside, emissions from vehicles and other machinery add nitrates, sulfides and particulate matter such as soot to the air. Volatile compounds both within and outside the home add their vapours to the air. Natural processes do remove some of these pollutants, but it takes time. Thus the air in your home, or even surrounding your city, will have increased impurity levels compared to the worldwide average, or what is "ideal" fresh air.
As regards physiological effects, oxygen concentration is less important, as the hemoglobin in your blood is remarkably efficient at oxygen transport; however, carbon monoxide (naturally occurring, or from vehicle emissions etc.) binds to hemoglobin much more readily than does oxygen. As a result, CO exposure can starve the body of oxygen somewhat, and it takes some time after exposure to CO for the body to eliminate it. Carbon dioxide comprises the body's primary stimulus to breathe, and as such elevated levels of CO2 can lead to increased respiration rates, with the associated fatigue and changes in blood chemistry that that implies. Organic compounds and toxins in the air have the same effects as those poisons delivered by other means, and although the body has mechanisms to deal with such toxins, you can be asymptomatic for poisoning but your body is still allocating energy resources to eliminate the toxins. Airborne particulates, in addition to possible toxic effects, are eliminated from the body by various processes, consuming energy, and in some cases, cause damage to the lungs which reduces their efficiency.
In the presence of fresh air (nitrogen, oxygen, argon, water, carbon dioxide and trace compounds), the concentration of pollutants is low, making it easier to eliminate any existing pollutants in the body since there is a concentration gradient between inspired and exhaled air.
Physiologically, this is rejuvenating, and it comes as no surprise that you would become aware of this at an objective level. | 10 | 20 |
ELI5: Object Oriented Design | Hi.
I am currently studying computer science at university. I am a first year in need of some help.
Please could someone explain to me the main principles behind Object Oriented Design. I am finding some of the concepts hard to get my head round.
Thanks in advance!
**EDIT 18:04: Thanks for the answers. If any of you could explain the concepts of interface and polymorphism then that would be excellent.** | It's helpful to contrast with other design philosophy. If you want to accomplish a task (especially large ones) there are many different ways of doing it.
In procedural programming, you would just make a list of all the things that need to happen, and then just do them in order. This can be a mess for a larger project.
Object oriented design is more structured and abstract. Typically, you break ideas up into 'objects', and then define how objects interact with each other.
For example, say you're making a video game which has bad guys that can shoot at you. You could define a 'class', which is a template for objects.
class BadGuy:
def __init__(self, damage, health):
self.weapon_damage = damage
self.health = health
def attack(self, other):
other.health -= self.weapon_damage
def get_attacked(self, other):
self.health -= other.weapon_damage
if self.health <= 0:
self.die()
def die(self):
...
This helps to organize code immensely. Since objects share so many traits (health, damage, etc.), this lets you write the base object that can be extended and specialized from there. The __init__ function creates an object (referred to as self). For example:
badguy1 = BadGuy(damage = 5, health = 10)
boss = BadGuy(damage = 40, health = 120)
badguy1.attack(boss) | 20 | 28 |
There is a strong incentive to discriminate against gays and blacks in hiring for small businesses, and in some cases women & religious. CMV | * Fair hiring laws exist
* These laws give legal teeth to people of protected classes
* There are often equally qualified candidates that are not of protected classes
* Lawsuits of these types are often hard to defend, even when firings are justified
* It is orders of magnitude more difficult for people of protected classes to file a lawsuit successfully that they were not hired because of this reason
* It is more likely that a person of a protected class will threaten or file a lawsuit if hired and then fired, than a lawsuit is filed for not being hired.
* Protected class members are more likely to associate their firing to their protected class
* I am unconvinced "diversity" is a tangible benefit when the liabilities are very real and measurable.
Therefor it is logical that when a candidate of protected class presents themselves as being equally qualified to a non-protected class candidate, the logical hiring choice is to discriminate.
In small companies this is easy to get away with and certainly the smarter business move. Since hiring liabilities have a disproportionate impact on the long term viability of a business when it is small. | In 2012, the Equal Employment Opportunity Commission, tasked with enforcing federal discrimination laws, charged employers with 33,512 violations based on race.
There are about 42,000,000 racial minorities in the United States.
Let's be *conservative* and say only 75% of them have jobs.
31,500,000 minority workers, divided by 33,512 complaints, equals .00106, or .1%.
So, less one-tenth of 1% of racial minority hirings result in a discrimination charge.
Many of those charges are probably based on *valid* complaints, so the percentage of frivolous complaints is even smaller.
Based on these numbers, the statistical risk of hiring a minority employee are completely negligible unless you're looking for a reason to not hire minorities in bad faith.
Moreover, NOT hiring an employee on the basis of race, gender, etc., is a much more significant risk in itself, since it's an actionable EEOC violation. Also, discriminatory non-hiring probably accounts for many of those 33,512 cases. | 16 | 29 |
[Mass Effect] Why does Shepard only ever take 2 people with her on missions? | At least in 1, it's not a limitation of the Mako, since on Feros we have an extra person along for the ride. Some missions of course require some more subtlety, but some really would benefit from more firepower. Hell, in 2 they have to get all your companions off the ship on a mission so the collectors can attack. | Mission parameters dictate a small strike team would be most effective give the proximity to superior hostile forces. 3 soldiers draws less attention than a full squad would. And bringing 3 capable fighters can handle most threats long enough for reinforcements to arrive from the Normandy. Stealth and precision is the goal of Spectres not overwhelming force. | 40 | 25 |
CMV: It is morally permissible for parents to teach their values to their children | Some people argue that it is wrong for parents or society at large to teach religion, moral values, or societal ideas to their children on the grounds that they are brainwashing the youth. I disagree with this assessment: I think the concept of parents and society teaching values to children is sound; the issues come in *how* parents do so.
The core sentiment of those who argue against “parental/societal indoctrination” seems to be that each child is a blank slate that he should fill himself. Ostensibly, this allows every child to become his own individual person, unburdened by societal restraints or indoctrination. Though attractive in theory, this idealistic vision of “individual free thought” is utterly unrealistic:
- By nature, humans are social animals. Children are born into a society, and a quick look into sociology reveals that this has massive and inevitable implications. It is simply impossible for someone to *not* be influenced by societal ideas; thus the idea of “thinking for yourself” is on some level absurd. People are shaped by society before they shape it.
- Critics invariably focus on the negative aspects of societal and parental influence, ignoring the benefits of learning societal norms and values. Pretty much everything you learn comes from the teaching of parents or others society; manners, etiquette, and morals are closely linked to the religion and social structures that get so much flak.
- I think critics miss a core reason people have or adopt kids: they want to raise the next generation and mold them in their own image. This paternalism is, I think, innate to humans: we desire for *our* tribe to grow and prosper. People don’t have kids to raise them as utopia-minded thinkers. Understanding this, the problem shifts to the fact that reproduction is not really regulated: pretty much anyone who wants to have children can, without regard to finances, beliefs, or morals. Trying to control who does and doesn’t get to be a parent though is morally problematic and basically impossible.
- Religious beliefs, political views, and other beliefs can change over time. It’s common for people to question what they were taught as they discover new perspectives. In other words, teaching one doesn’t mean that other perspectives are invalid. If you don’t agree with what you were taught, you can find a new perspective.
- Undoubtedly, teaching intolerance (racism, etc.) is a problem. That, however, is covered under the paradox of tolerance: society should not tolerate intolerance. In other words, there are some reasonable limits to what is permissible to teach; teaching your kids to revere Hitler or kill Muslims is not ok.
- Ultimately, the *way* children are taught is what can cause problems. It’s perfectly possible to raise a kid in the Catholic faith without stifling their free thought or teaching them to hate gay people. Teaching is not equivalent to indoctrinating the way critics claim. It’s also true that good parents will be supportive or at least respectful of their children.
A related concern is that having expectations of children is wrong because it inhibits their freedom of expression. First, there’s nothing wrong with expecting your child to become a productive member of society—parents want their children to be successful, and getting a college education and stable job is a solid way to that. That aspect is a little ridiculous to criticize.
Second, some people seem to believe it’s wrong to make ANY statements about a child. This logically leads to stuff like [this](https://youtu.be/12t7PYilNQQ), where the presenter is raising her child as “gender creative” because gender labels are apparently inseparable from gender stereotypes. I think much of the same applies: exposing children to ideas and having expectations isn’t inherently bad, though how parents react if those expectations are broken *can* be bad. It’s a fine line, but the alternative proposal of “letting the child figure it out” is not feasible. Children are dependents of their parents because it takes a while for them to figure out who they are and what they believe.
This is probably controversial so CMV away. | Teaching a child social norms in the sense of "This is what others expect of you, and if you don't conform, you will suffer a social penalty." is appropriate. Teaching morality in the sense of "This is what I, and most of society believe to be right and wrong. If people didn't agree on these moral principles, society wouldn't function very well." (and then providing reasons), is also appropriate. This teaching should have a solid, empirical foundation, and you should be able to justify it to a child if asked.
Teaching a child that God created the Earth in six days and rested on the seventh, or that the Earth is only 6,000 years old and humans lived with dinosaurs, or that gays should be hated because God said that "If a man lies with another man as with a woman, they shall both surely be put to death. Their blood will be upon them." is child abuse. This is not teaching, but indoctrination. Furthermore, religion is totally unnecessary if the goal is to raise children to behave in a moral, socially appropriate manner. Exposing your child to religion is fine. Teaching it as fact, or worse, punishing your child if he rejects it, is not.
If you can't justify a statement with facts and/or logic, you shouldn't teach it as absolute truth to your children, and you certainly shouldn't punish them if they don't agree with the statement. You should also be willing to admit you're wrong if the child presents a convincing counterargument to a statement you thought was true. | 20 | 40 |
ELI5: how do rich people with massive net worth(Ranging from $10 million to hundreds of millions of dollars) manage their money? | I am curios to see how do they manage such a large amount. | I would have to say most if not all hire professional money manager and let them handle it. It's kind of like retirement. They get an amount to live off of each month and they can tell the money manager to give them more if they want to buy a new Gulfstream. | 30 | 50 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.