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Are 'pure', 'a priori' and 'transcendental' interchangeable in Kant's use? | For example when Kant talks about **pure concepts of the understanding** it is clear to me that this can als be said as **a priori concepts of the understanding** but could I also use **transcendental concepts of the understanding**? | Pure = does not require any experience to have (e.g. space, time, possibility, substance).
A priori = does not require any specific experience to have. Could require none or just any experience (e.g. morality).
Transcendental = related to the necessary conditions for the possibility of something (e.g. understanding at least some English is a necessary condition for the possibility of reading a book written in English, so it is a transcendental condition for reading a book written in English). When Kant is talking about something being transcendental, he usually means "a transcendental condition for experience". | 18 | 17 |
How graduate school works. | How do people get in and what do they do there? What makes it different from being an undergraduate? | Graduate school is so diverse that it doesn't really make any sense to lump it all into one category.
As a general term, graduate school is some sort of education beyond the undergraduate. Generally, a specific field (say, chemical engineering) is chosen before beginning the program. The programs may last 1-6 years or more, depending on the degree, institution, and field.
A Master's degree is sometimes a terminal degree (meaning that it is the highest degree in a given field). The Master of Business Administration (MBA) is a terminal degree. The Master in Social Work is also considered a terminal degree, even though there is a Doctorate of Social Work (though it is uncommon and very specialized).
Master's degrees in the sciences are generally not considered terminal degrees, as they are often used as a stepping stone to get a doctorate (Ph.D.).
Master's degrees may be coursework-only or may include a research/thesis/project aspect.
Doctorates (Ph.D.s) generally require several years of research and a dissertation in addition to coursework. Depending on the field and institution, this may take anywhere between 3 and 8 years.
There are other graduate degrees, for example in law (JD), medicine (MD), dentistry (DDS), education (EdD) and others. Each program is specialized and includes the highest level coursework available in that field.
The application process is very similar to undergrad. Main differences include:
* taking the GRE (and, if applicable, individual subject GREs), LSAT, MCAT, GMAT, or other instead of the SAT
* essays topics are limited to professional/research experiences
EDIT: added more graduate tests | 25 | 37 |
ELI5: Why can't people with dementia draw clocks correctly? | There are several aspects of the clock-drawing test. You have to plan ahead, and maintain a symmetric position for the numbers. Then you have to add hands, pointed at the time the doctor asks you to use, which is often ten minutes before 4 or ten minutes after 11. This means putting the hand on the right side of the number. There are many metrics for scoring how well someone draws the clock face, and there is pretty good correlation to more involved tests. That's why the clock test is so common, it's super easy and doesn't take any equipment besides a pencil. If there is a change in scores, then it might be worth a more involved test. | 67 | 64 |
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ELI5: Why did NASA keep us waiting before they revealed what they found on Mars? | It's not like they're a company coming out with a new product and they want to build up hype. They're a part of the government that works for the people. Why would they intentionally withhold information from the public for a period of time? | It takes time to vet the information a few more times.
Then there is how do you share the info. Sure the could have just put a one page document out on the web, but they wanted to do everything to give the best context possible, so they gave news agencies time to coordinate for it, get the group of guys out there to discuss it.
NASA is also an agency fighting for funding, making sure everyone knows what is happening and putting them in the spotlight is a nice bonus to show they are still doing work.
And about your govt agency comment. NASA does not exist for the convenience of the public. Is the Motor Vehicle Agency open when it is best for you? No, they are open and working the hours which make it most economical for them to do the job assigned. | 29 | 30 |
How would an anarchic society, which is based on cooperation between individuals and a lack of hierarchy, deal with the 'bad' people? | There will always be individuals that have a psychological need to do harm to others in various ways. They can be labelled as 'bad' by the society as a whole just from an ethical standpoint (since legality is not a valid reason in this context).
How can an anarchic society get rid of said individuals if there are no rules (or no one to enforce them, since just the existence of enforcers would generate a new hierarchy)? | Anarchists have formed successful military organizations, and they could likely form successful public safety organizations as well. These would have to be carefully run under transparent, democratic procedures, as one could readily imagine the potential for corruption. | 34 | 101 |
ELI5: How does "Auto focus" works on cameras? | Like, how can the camera decide that the object is in focus? How is the distance measured by using just light (I assume so since it's normally very difficult for the camera to focus in low light environment) | To add to the other answer that's here already with a tiny bit more detail:
The first uses infrared (IR) light, and the sensor in the camera measures the time it takes for the IR light return to figure out the distance. Fancy computer calculations that already know all the variables (lens length, aperture, etc etc) then figures out the physical distance to the target and adjusts the lens to the proper focal length. It can be confused by other sources of IR light in the room, or something interfering with the IR light coming back to the camera's sensor.
The other type works exactly as stated, looking for contrast points in the photo and then changing the focal length and looking at the same points. It compares the two results to determine which gives the clearer lines. This type of autofocus doesn't know the distance it just looks at the contrast points. It can have issues with changing lighting scenarios and moving targets because of this. This type can be slower to "hunt" for the focus sometimes, and lower light can make it harder to use as there's generally less contrast to be had. | 20 | 149 |
What was the region of the brain that allows us to read used for in cultures without a written language? | And for that matter, how do we already have an *entire brain region* dedicated to the use of a specific tool that's still a recent innovation, evolutionarily speaking? | Reading uses a few regions. Namely the temporal lobe, the broca's areas and the angular and supramarginal gyrus.
The first two are also used in speech for phoneme and sound recognition and for language comprehension respectively. The third set are responsible for linking the areas of the brains so the shapes can be linked to sounds then word and meaning. | 43 | 56 |
Is it possible for a species to have an evolutionary trait that wasn't a result of survival of the fittest? Essentially just a trait that tagged along for the ride as the generations went on? | Survival of the fittest is a loose term.
All traits are the result of evolutionary processes working; but that does not imply that all results are the ‘fittest’.
Any mutation that does not kill the individual and allows breeding may be continued for some time; over time useless (doesn’t help survival or breeding success) traits will tend to be breed out by traits that do
This is a massive simplification. | 41 | 26 |
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Overpopulation and resources: criticisms against Malthusianism? | Hey everyone,
I had a discussion with a friend who is a Malthusianist. And while I had never heard of his exact theories about overpopulation before, I am familiar with similar ideas related to demographics.
Now, one of the first things that struck me was that it sounded awfully similar to Social Darwinism. It also seems puts heavy emphasis on the population rather than factors governing that population, making it a mathematical function instead of social/world politics.
Can someone who knows more about Malthusianism explain and introduce me to legitimate critiques of the theory ? | Population statistics show developed countries as either maintaining or slowly decreasing in population. It's very well researched and is a trend across dozens of developed nations. The long and short of this is that global overpopulation is currently very unlikely. | 33 | 44 |
Should physicians spend more or less time in research? | I've noticed an increased push for physicians to work on research. Why is this happening?
I would have assumed physicians would want less research demands, so they can focus on treating patients. | I’m research faculty in a medical school. Most physicians aren’t qualified to do research. Those who are, often have trouble because academic institutions need clinical income more than they need a half-time researcher. There is definitely a push to get research and clinical faculty to collaborate so we’re on the same wavelength. We all share the goal of helping people, but they are very different career trajectories. | 32 | 15 |
Carnap, Quine, and the return of metaphysics | I've been trying to understand why metaphysics made a comeback in the second half of the 20th century, and have a couple questions in relation to that. My basic understanding is that Quine made the case that we could make a principled decision between ways of speaking that make all the same predictions...whereas Carnap thought such a decision could only be made on the basis of specific use cases. If this is right -- and I'm not sure it is -- it's unclear to me why people take Quine to have successfully taken on logical positivism. Specifically, I'm confused by a number of points regarding "Two Dogmas of Empiricism," which attempts to reject positivism's analytic / synthetic distinction, as well as their foundationalism / reductionism.
First, why does logical positivism need the analytic / synthetic distinction? And does the failure of this distinction in particular have any consequences for the status of metaphysics?
Second, does Quine's anti-foundationalism have any consequences for the status of metaphysics?
Thanks for answering, and I appreciate the notice if I got anything wrong in laying these questions. | > why does logical positivism need the analytic / synthetic distinction?
I think it's helpful to follow the language of Carnap's *Empiricism, Sematics, and Ontology* and note a distinction not just between logical and empirical questions, but also between either and practical questions.
Carnap relies on these distinctions because they are what underpin his distinction between science and metaphysics. Science is what resolves logical and empirical questions, while metaphysics is what resolves practical questions.
Conversely, if we deny that we can make any clear distinction between these kinds of questions, then we deny that we can make any clear distinction between science and metaphysics--at least as Carnap construes them.
So Carnap needs this distinction between kinds of questions in order to underpin his distinction between science and metaphysics.
> does Quine's anti-foundationalism have any consequences for the status of metaphysics?
Quine denies our ability to make clear distinctions between these kinds of questions, and, accordingly our ability to make a clear distinction, like the one Carnap makes, between science and metaphysics.
The slogan that Carnap killed metaphysics and then Quine brought it back is rather an oversimplification. They had very different views about what metaphysics is--in some ways, Carnap's is more continuous with traditional views about metaphysics than Quine's is, so there's something unsatisfactory with this slogan.
For Carnap, the upshot is that, consistent with the tradition through Leibniz and Kant, metaphysics constitutes a distinct field which provides a foundation for the sciences. But, following the radicalization of Kantian agnosticism which takes shape especially in Dilthey and Nietzsche, his major sources for this, he denies that metaphysical questions are answerable on strictly rational grounds, and construes our answers to metaphysical questions to be an expression of our life-feeling--responsive to things like our constitution, our socioeconomic class, our place in cultural history, etc.
For Quine, we get rather the opposite situation. The downshot is that the traditional distinction of metaphysics as a distinct field is undermined. But the upshot is that metaphysics, no longer clearly distinguishable from science, can be addressed on rational grounds just as much as science can--as indeed, they're not clearly distinguishable.
So Quine rejects the traditional view of metaphysics as a foundation of science, but does so in a way that undermines Carnap's non-cognitivism about metaphysics.
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ELI5: Why did it take 1 year to construct the Empire State Building in 1930 but 7 years to construct One World Trade Center in modern times? | Shouldn't modern technology speed up the construction process? | Modern technology and construction processes are more complex which takes more time. They also come with more safety regulations both in construction and in what workers are allowed to do. The Empire State Building was also much smaller. | 5,301 | 5,593 |
Eli5: how does DNA code editing work? | I assume you mean how we genetically modify organisms?
Step one is obviously to figure out which gene you either want to insert or remove. That's just long, tedious work sequencing the genome and then doing experiments to figure out what each gene does. Think this bit of DNA codes for a certain protein? Get rid of that bit, let the organism grow, and see if it still makes that protein. If not, your hypothesis was correct! We can use all kinds of chemistry, including borrowing the enzymes that living things use to copy and edit their own DNA, to chop up the DNA we want to insert into something else and isolate the section we want. We can use other enzymes and chemistry to combine different pieces to make bigger, more complicated sections of DNA that code for multiple proteins.
To actually manipulate the genes, we have a couple different methods. One of the coolest things is almost literally a "DNA gun". It launches your bits of code (the base pairs) at the target cell's nucleus with a lot of energy, smashing into its DNA, hopefully with enough energy to smash them together. Obviously, this has some problems: you may not get them to merge together, you may just smash everything to bits. You may also end up putting your new code in a bad spot on the DNA, that either means it can't get used, or messed up an important bit of code that was already there so the organism can't grow correctly. After firing your DNA gun, you sit back and wait to see if it grows and how it grows to see if you got the results you want. If you did, you save that specimen and let it reproduce, preserving the change in new generations.
The more accurate way that we use now is to use a species of bacteria (*Agrobacterium tumifaciens*) to insert the DNA. The bacteria almost works like a virus, inserting part of its own DNA into the plants it infects. Normally, this means the plant starts growing tumors and dies. But when we genetically modify the plants, first we change the bacteria's DNA to the code we want the plant to have. Then we infect the plant with the bacteria, which inserts that new code we want the plant to have, then it dies off, leaving us with our new plant. This is way better than bombarding the plant's DNA because we can modify the bacteria to target parts of the plant DNA that we want changed, making it far more accurate. It's also far more likely to, you know, not smash the target DNA to bits. To change the *bacteria's* DNA, we use the same bombardment techniques, but recall that part of the step is to grow the organism to make sure it has the DNA we want in it: that's very time-consuming for a plant like corn that takes years to mature. But bacteria grow in hours or days, so it's far easier to check. In addition, the bacteria DNA is a lot simpler, so it's much easier to affect the part we want. We also sometimes use a type of virus called bacteriophages - viruses that only infect bacteria. Viruses work by changing DNA, right? So get the virus to insert its DNA (which we've modified) into the bacteria, which then inserts it into the plant. Viruses are even easier to work with than bacteria, because they're not truly alive it's harder to mess them up and "kill" them. | 15 | 54 |
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ELI5: Why do researchers who do tests on mice have to comply with strict ethical regulations, and yet it is legal for me to use mousetraps and very painful poisons to remove them from my house? | Research is just highly regulated in that any research animal must be treated with the utmost respect and dignity because its life provides us with valuable information that helps either their species or ours.
Pest animals are slightly different in that they have the potential to carry disease, so they must be removed from the home or else you/your family is at risk.
Poisons aren't the most humane things, but the snap traps are actually very humane and cause instant death through severing the spinal cord. They actually use snap traps in field research. | 66 | 158 |
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ELI5: Why are banks allowed to use money in way they cannot give people their own money back? | Consider a small village with one bank and no outside help. An individual wants to build a factory. So he takes out a loan.
In future this factory happens to be very successful thereby creating lot of growth.
However to begin with the loan money has to come from somewhere? The idea is banks which collect small to large savings from the villagers can afford to loan a part of their savings. This is based on the statistical assumption that normally everyone wouldn't take out their money simultaneously. So the bank can invest a % of the money it has.
The bank makes money by fee and loan interests. The villagers get safety and sometimes interest on their savings. The economy grows as a whole.
The problem is during unstable times, wars, recession, rumors suddenly a lot of people start taking out their money (this is called a run on the bank). This violates the underlying statistical model.
On a personal level saving money is a good habit. On a collective level just plain savings isn't good because there is no economic growth. Banks ideally transform the personal savings of a society into engine of economic growth. | 24 | 25 |
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ELI5: How are cigarettes still legal? If they were a medicine for a disease the FDA would have them banned for their lethal side effects | It is probably because our laws are often determined by the prevailing culture and social norms, and not based on logical or scientific reasons.
For example, in the early 1900s it would have been illegal in some states for inter-racial couples to marry. And slowly through abolition and expanded human rights those laws were overturned.
We're starting to see how prevailing society and culture is starting to become more accepting of marijuana and LGBT rights. So now many states have legalized marijuana and gay marriage.
Why are cigarettes legal? The same reason why alcohol is legal. They are socially accepted drugs that we don't frown upon in our culture. | 385 | 340 |
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How much can boiling a pot of water raise the humidity in a building? | My question is because at my cabin that is heated by a wood stove it gets very dry and we always put a pale of water on the stove to counter act the fire. With out the water every time you walk around and you touch something you get a static shock. With the water on the stove it stops. I'm just wondering how much change a small bucket of water can make in a whole cabin. | It takes a small volume of water to substantially increase the humidity of a reasonably sized room (ignoring losses of water to condensation etc.).
Example: to increase the humidity of a 20 m^(3) room by 50% at 20^(o)C, you'd only need to boil approximately 170 ml of water.
Of course the volume of water needed increases when the temperature of the room increases. For example, at 30^(o)C you'd need 300 ml of water. | 19 | 22 |
Are the most popular searched terms on Google on Wikipedia a good measure of public interest, or public curiosity, in a subject? | An indicator is exactly that: an indication of X. Often times we can't measure X directly because it's unobservable or unfeasible.
Campbell & Fiske (1959) were the first real champions of triangulation when isolating constructs (Fun fact: that '59 paper is the most cited paper in all of psychology).
Your best bet is to attack this construct in as many different ways as possible. If you're looking for how popular a topic is, how can we measure that?
We can measure # of google searches (or %), wikipedia edits/articles; headlines that include that topic in major news outlets (online vs offline); you can also measure it using dissertation or research papers on the topic.
Get creative!
The idea here is that all of these measures will converge on the same idea: "how popular is X at a particular moment in time". Each indicator will miss the mark slightly, but will hit the mark in its own unique way. We hope, as researchers, that if we spread out this risk (what Campbell & Fiske called heterogeneity of irrelevancies), the part where all indicators overlap will be the part you're interested in. | 44 | 65 |
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CMV: Gender Dysphoria (Being transgender) is a biological, mental disorder, and should be treated like OCD or Depression. | Gender Dysphoria, also called Gender Identity Disorder, refers to feelings of not belonging to the gender one is assigned at birth. People who have these feelings are referred to as Transgender. While many will say these feelings are natural and relate to one's true identity, I maintain that it is a mental disorder and instead of supporting those who wish to be a different gender we should urge them to seek medical treatment such as psychotherapy.
There have been numerous studies to support my case. Coolidge et al. (2002), performed twin studies to determine that Gender Identity Disorder is 62% heritable. This shows that there is genetics play a large part in the disorder.
Many transgender people wish for gender dysphoria to be declassified as a mental disorder, as it "reinforces the binary model of gender." Here is an extract from an article on the subject: http://m.ccp.sagepub.com/content/7/3/352
However, I support the continued classification of Gender Dysphoria as a mental disorder. Studies have shown that the disorder can result in anxiety, depression and suicide. This may be easier to prevent if we treat it as a serious disorder rather than simply celebrating people's differences.
I'd like to see others views on the subject. Perhaps I am wrong and we should not classify gender dysphoria as a mental disorder, but celebrate differences between people.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[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)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | It is treated, but the treatment for them is to make the body match the mind rather than make the mind match the body. It greatly reduces the rate of suicide and greatly increases quality of life for them so that is the best treatment. Why do you want to ban the best treatment? | 59 | 28 |
Why does it take several minutes for our eyes to adjust to the dark, when our pupils shrink so quickly? | It's not just the pupil that helps us adjust to bright & dark situations.
There is a chemical called Rhodopsin that detects when photons (light) hits it. The light breaks down the Rhodopsin, and it takes a while for it to reform/replenish.
So when it's bright and you go into the dark (or stop looking at a bright light when it's dark around you), the time it takes for you to adjust, is just the time that it takes for the Rhodopsin to replenish. | 30 | 73 |
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ELI5: Difference between Euclidean and non-Euclidean geometry? | There are 7 postulates in Euclidean geometry - baseline rules that underpin the entire logical system.
Non-Euclidean geometries involve changing the 5th postulate - also called the parallel postulate - to something else. You can look up a more formal statement, but the parallel postulate is the one that ensures that two parallel lines can never meet.
Normally, non-Euclidean geometries deal with situations where the surface you're working with is curved. | 16 | 19 |
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[Final Fantasy 6] Where did Kefka get the power to single-handedly kill 20 espers in one blow? | Kefka had two main advantages:
1. Immediately before that happens, Kefka and the Emperor had *just* figured out that the full power of Espers can be transferred by using Magicite when an Esper dies. Kefka has the full support of the Empire and all its mad magitech science, so they gathered up all of the Espers they still had access to, turned them into magicite, and sucked all the power out of them. If game mechanics are to be believed, this would require Kefka killing a shit-ton of things for exp, but he would hardly have an ethical problem with running around murdering things for power. Hell, they'd probably assembly line that shit, capturing monsters, battering them down to one hp, and then delivering them to Kefka to give the final blow.
2. Kefka has a unique power to nullify Espers magic, making them essentially powerless against him. This appears to be a more developed version of Celes' Runic ability, and it makes sense that the Empire would keep working on developing a better version after Celes betrayed them. | 26 | 34 |
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CMV: Children should not be punished for bad grades. | With the holiday season coming up, I have seen several tweets spark joking about kids/teens knowing they’re no longer going to get anything on their Christmas wishlist due to bad grades. When I was younger, I also got grounded for bad grades, sometimes even spanked. I do not believe in this method of discipline (for non-rebellious bad/failing grades). Here’s why:
1. I believe it projects a message of poor problem-solving skills as a parent: grounding or punishing your child for poor academic performance is an easy cop-out rather than dealing with the problem at hand.
2. I believe children (who aren’t being lazy, skipping school, etc.) who are producing subpar grades in school may simply not understand the content. Even if I can’t personally help my (future) child with his or her homework, I would ask other relatives, contact the teacher, or reach out to a tutor/friend who could assist.
3. Revoking toys, games, etc. from children don’t really teach them the importance of making good grades. Children should know the content not only for the benefit of passing the class, but to prepare them for future classes, as well as knowing basic skills once college comes around. If nothing else, they should be able to help their own kids with these same problems later in life!
4. Lastly, I believe punishing children for something they do not understand is merely torture, not fair, and counterproductive. Let them bump their heads & mess up a little. Put them on the spot and teach them the importance of consequences. Furthermore, your children should never be afraid to show you a report card out of fear or embarrassment. Parents should be of help and support.
*I am not a parent, I am 20-years-old. Maybe my mindset will change later in life. I’d love to hear from both parents and non-parents! | Is the child getting poor grades because of a lack of understanding, or because they actively choose to not complete work / study?
Those are two different scenarios, and should be treated different. | 29 | 24 |
ELI5: How do plants circulate water and nutrients throughout their system without a heart? | As far as I know, plants don't have any kind of moving parts that help move water and nutrients from their roots to their crowns. So how do they do it? How do plants work against gravity?
It would make more sense to me if plants worked like fungi, spreading throughout the earth until they're ready to reproduce, but no, upright plants are the whole organism. Is that not, like, super weird?
Plants are so weird. Like, "Hi, I'm a plant. I eat sunlight and communicate using mycorrhizal fungi. I have no muscles, but still break through concrete slabs. I have no heart, but still move water from my roots to my leaves." | Osmotic pressure and capillary action. Osmosis is the force that keeps pure solvents (i.e. water) from flowing through a semipermeable membrane (i.e. the cell wall). This keeps structures in the plant from drying out essentially. Capillary action is what causes water and nutrients to flow through a plant to the leaves and back down. Its pretty much physics. | 19 | 21 |
[Stellaris] Why is slavery so popular in the galaxy? Why not just build insentient automated factories? | Low initial materiel requirements. You need machinery to produce machinery; to produce more slave labour all you need is two slaves and judicious application of alcohol or equivalent disinhibitor. And you don't need an elaborate supply chain to keep them running. | 28 | 48 |
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[Equilibrium] If art is illegal. Why do new buildings have artistic elements to them? | Such as [this](http://3oneseven.com/wp-content/uploads/2011/12/equilibrium.jpg) and [this](http://d2oah9q9xdinv5.cloudfront.net/images/members/1/422/421599/20110721164338.jpg). | Citizen, if you feel that there is some form of aesthetic element in the construction of this building you are highly encouraged to write out, in full, your artistic analysis of this building's structural composition.
Please submit your writings, with your current address attached, to the Cleric's office as soon as possible. | 40 | 25 |
[Marvel 616] Can the Venom symbiote bond with Rogue? | What would happen in a physical contact scenario?
Also, since it can steal genetic attributes from hosts, could it steal a whole bunch of mutant powers? | The symbiote needs to bond with the host for a significant amount of time, on the order of days, before it can enhance the host and change it's own genetics. Unless Rogue's powers were subdued for any reason, the Venom symbiote would not be able to take root. Rogues latent power absorption would beat the symbiote, unless it was significantly made stronger by some other means.
If the symbiote was given time to bond, it would change it's genetics to match Rogue's, and then would be immune to her absorption powers once they are reactivated. It would then be able to take any powers it wants. | 102 | 154 |
ELI5: What gives the federal government the right to ban marijuana? And why can states violate that? [Serious] | I keep hearing about how the federal gov't bans all pot. But states still legalize medical marijuana, and in the case of Colorado, even recreational pot. So why can states violate the federal law? Also, if it took a constitutional amendment to ban alcohol at a federal level, why can they just decide to ban pot? | The Commerce Clause of the Constitution gives Congress the authority to regulate items that have a high probability of being trafficked across state borders.
States that have chosen to legalize marijuana are simply choosing not to enforce federal marijuana laws and have gotten rid of most of their own criminal & civil penalties on the sale and trafficking of the drug. If the federal government wants to enforce those laws they now must carry out enforcement itself.
Prohibition was put through as a Constitutional Amendment because proponents felt it would be a more permanent change than a simple law that could easily be overturned. Remember when Prohibition passed no Amendment had ever been overturned at that point. | 25 | 35 |
[Man of Steel]How did Clark's parents hide his powers in his youth | Throughout childhood, you have to get several check ups done, especially in your school years. In high school, you have to get multiple jabs done. One was for tetanus IIRC. Obviously any needle would break on Clark's skin. There are also blood tests you have to take as a child.
How did they get by without arising suspicion from schools and etc. | *Required* vaccinations are a fairly new thing, and even today many places have exemptions for religious or medical reasons. They could tell the state that their child is a Jehovah's Witness with an allergy to mercury and they'd be fine.
His powers also developed over time. Super Girl was bathed in yellow solar energy for her entire trip to Earth, and hit the ground with her powers. Kal El wasn't, which is fortunate: a toddler with the ability to fly and rip steel with his bare hands would be ... difficult to contend with.
The Kents knew he was an alien, and kept a pretty close eye on on his development, mostly because they feared that the government would come and take him away. As he matured and his powers began to reveal themselves, they taught him to 1. not kill anybody and 2. hide what he was capable of. | 221 | 213 |
Is it true that there are as many numbers between zero and one as there are between zero and infinity? A math teacher made this claim and I'm wondering how it could be proven. | You do this by showing there is a one-to-one mapping between these two sets.
First, we pair every number x between 0 and 1 with 1/x. These 1/x will be between 1 and infinity. So this shows there as many numbers between 0 and 1 as between 1 and infinity.
To get the pairing needed to show what the math teacher said, we instead pair every number x between 0 and 1 with (1/x)-1. So each number between 0 and 1 is paired with a unique number between 0 and infinity, and vice-versa. Thus, there are as many numbers between 0 and 1 as between 0 and infinity. | 26 | 18 |
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How respected is Dennett as a philosopher? | He's a leading figure in the "new atheism" movement, the "brights" movement, and also said he has "come out of the closet as a verificationist," implying verificationism is a taboo of some sorts. (logical positivism I believe). | He is very well respected by philosophers. You can find him discussed in academic introductions to philosophy of mind, there are articles by major philosophers responding to his work, he speaks at philosophy conferences, etc. | 21 | 18 |
ELI5: Why doesn't the United States have similar population issues as India and China? | Being rich, and womens' rights.
Poor people have more kids, this is a well known fact. People working on farms in rural India don't have tractors, they need as many people as possible to help work. They don't have social security, so they need lots of kids in the hope that at least one will be able to take care of them when they get old. They don't have insurance, so they need daughters to marry off to men in other villages (with different weather patterns) to support them during droughts.
Secondly, womens' rights. Everywhere in the world, the rise of rights for women leads to a decline in fertility rates. As women can work and earn more money, the opportunity (EDIT: opportunity *cost*) of having another kid increases. | 38 | 15 |
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ELI5 in economics, how does inflation work? | The money supply represents all the available 'working value' in an economy. By increasing the money supply, you can't change the 'real' value of the work, but now that you have more tokens representing the same economy, each token is worth less.
Let's look at an economy of 10 people, and a money supply of 1000. If you increase the money supply to 2000, then you have inflated the money by 100%. There are still only 10 people, though, and there is still only so much work those 10 people can do. Because of this fact, and because of the eventual distribution of the extra money, the money can only possibly be worth half as much as it was before. | 58 | 129 |
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ELI5: What is exactly meant when someone says they are a "consultant"? | I often meet people my age (mid/late twenties) who work in "consulting"...usually a male who majored in something like business or finance in college, likes to wear suits out to the bar, we all know someone like this.
Whenever I ask for an explanation of what they actually do, the typical answer includes a lot of words like "synergy" and "facilitating" and "networking between networks" and "accelerating profits", but they can never qualify any of those fancy terms in a "what do you do when you go into work on an average day" kind of way.
So what do consultants actually *do*? | Typically, they look at a specific area of how a company works. They identify what the company is doing right or wrong in that area. Then they write a long report with their findings, and charge the company lots of money. | 27 | 39 |
[MCU Infinity War] How did Thanos turn the Aether (Reality Stone), a liquid, into a stone? | On its own, it flows into different shapes and states, altering reality because that's what it does. Sometimes it's a liquid, sometimes solid, sometimes particle cloud, etc.
Once you have it, reality can be whatever you want it to be. You can fix it in any state you desire. | 47 | 21 |
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ELI5 why are tennis courts different materials? | Pro basketball always on wood. Pro football (US) mostly on grass. Why do tennis surfaces vary so much?
Or is it just green clay sometimes? | It comes down to what is easily available and, more importantly, what is easier and cheaper to maintain.
Historically, all courts were grass. That was the natural surface available. However, in order to have a playable grass surface, it needs a *lot* of maintenance. You need the right kind of grass (and soil), and it constantly has to be mowed and kept up to standard in order to have consistency. The grass will deteriorate as the match our tournament goes on, and takes longer to dry out after rain.
Clay courts were a great alternative, especially in environments which were less favourable to maintaining grass courts (Europe, South America). With advances in materials and manufacturing, hard courts became more feasible and are commonly used for purpose-made arenas. Grass courts are maintained more out of tradition.
In contrast, football is always on grass because it is normally the most versatile surface for the sport. The quality and condition of the grass is not important, as the majority of the sport involves running and the interaction of the ball with the grass is not as important. Artificial surfaces were introduced to reduce the maintenance associated with grass. Basketball was invented to make use of gymnasiums that were already built (with wooden floors), and "pro" basketball always uses courts that are made to a specified standard. Unlike tennis - advances in technology haven't shown a need to change the playing surface. | 91 | 107 |
Do plants have immune systems? | Whether it's bacteria, fungus, or insects, do plants have a way to fight off deadly organisms? Obviously trees and other plants don't have white blood cells or immune systems like animals, so I was wondering if they had a way to fight off diseases and parasites. | In woody plants, there are four "walls" of defense from infection.
The first is the closing up of vessels in a wound or around a site infected with a fungus/virus/what-have-you. This inhibits the movement of pathogens/decay up and down in the stem of the plant.
The second is the hard rings of early and late wood which inhibit spread of infection or decay tangentially, or in and out of the plant.
The third is the ray cells which compartmentalize a wound or infection radially.
The fourth and most effective wall is the layer of hardened wood that will grow around the outside of the infection/wound that will block it off from the outside (like a scab).
In effect these four walls compartmentalize an infection or wound so that it can't harm the rest of the plant.
Another big part of herbivory prevention is secondary metabolites. These are chemicals or structures a plant makes to create defenses. There are flat-out poisons like caffeine, cocaine, nicotine, stricnine, terpentine, etc. that will adeversely affect anything that consumes the plant. There are also things like wood, thorns, tannins, waxes, and aromatic oils that will make plant tissues indigestible to infection or insects, armor it, or just repel herbivores. | 55 | 60 |
How does listening to music while studying affect the human brain? Is it beneficial or harmful to the studying? | Music can often interfere with studying because of the scope of your working memory. Working memory is a cognitive system with a limited capacity that is responsible for temporarily holding information available for processing. It is necessary for the information to be manipulated in the working memory to be stored in the longterm memory. Since music and studying do involve some of the same canals one can interfere with the other. However, if you do study while listening to music, recall of the information will be more successful when the same music is played! This is because context plays an important role in our memory: greater congruence between situations of studying and recall will result in better recall of the information. | 11 | 26 |
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[DC] How do the different Green Lanterns compare to each other? | I've heard they have different styles of contructs, but what does this mean? Are the styles more or less suitable to different tasks? What about the Lanterns themselves? How do they differ from each other or from other colour Lanterns? | All the corps have basic similarities such as flight and a protective energy shield, with various differences.
- **Green Lanterns** can make various constructs (Be if offensive or defensive). They draw their power from willpower.
- **Yellow Lanterns (aka Sinestro Corps)** are very similar to green in that they can also make constructs. They draw their power from fear.
- **Red Lanterns** (With *rare* exceptions) cannot make constructs. The ring replaces their heart and without it on they die. They can spew forth acidic blood that burns whatever it touches. Anyone wearing a red ring flies into a mindless rage and acts like a wild animal; It takes incredible strength or willpower to resist this. They draw their power from rage.
- **Blue Lanterns** can recharge Green Power Rings simply by being near them, and can even overcharge rings to make them more powerful. Without being near a Green Power Ring, these rings are almost useless and can only provide flight and a protective shield. When near a GL they can create constructs (Which tend to be more defensive but can be offensive) and can heal people. A Blue Lantern is one of the few things that can successfully cure a Red Lantern. They are powered by hope.
- **Agent Orange (Larfleeze)** is the only creature with an Orange Power Ring. He is powered by a never-ending greed and gluttony. Whenever he eats or kills someone he is able to make them an orange construct, capable of acting independently. These constructs seem to have independent thought but obey Larfleeze. His constructs can absorb the light of other rings.
- **Star Sapphires** wield the violet light of love. They are exclusively female. They can tether to someone they love and know their location as well as any danger they are in. They are able to encase people in crystal, having them emerge later as Star Sapphires. Their lights cannot be absorbed by Orange constructs.
- **Indigo Tribe** wields the purple light of compassion. Their corps is made up of reformed criminals whose emotions have all been suppressed by their rings, similar to brainwashing. They can emulate the powers of all other corps, in addition to being able to teleport great distances.
- **Black Lanterns** are fuelled by death. This corps is made up of deceased (Or formerly deceased) individuals. They consume the living to increase their own power. They cannot be killed except by the combined light of the entire emotional spectrum. A person wielding a black ring is able to raise the dead to serve them, but they do not make constructs.
- **White Lanterns** have the typical lantern powers. They can channel the powers of all the other rings (Aside from black) and can destroy Black Lanterns with ease. | 54 | 60 |
ELI5: in baseball, why does the catcher call out pitches to the pitcher? What does the catcher know that the pitcher does not | The pitcher and the catcher both need to know the pitch. One of them has to call it out. The batter is looking directly at the pitcher, so it makes more sense for the catcher to call them out. The pitcher will then nod or shake his head to accept or reject the pitch suggestion. | 293 | 145 |
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Benefits of Zotero/Other citation managers vs BibTeX? | Hello, I am having a hard time understanding the benefits of using Zotero or other reference managers outside of just a BibTeX file.
All the papers I write are in LaTeX because of my field, pretty much all conferences and journals require this. Right now I just keep a single very long BibTeX file then easily add references to my LaTeX document.
As it is, I see almost no benefit from using Zotero or something similar to manage my references. And pretty much every single tutorial on how to use Zotero is more or less how to install it, the browser addon, and add new references to zotero (and add them to a Word document).
I suppose adding tags and occasionally reviewing those tags to see what papers might be related/I've forgotten about could be useful, but I currently use Obsidian where I take my own notes to do this ideation process. And I could see this becoming extremely unwieldy.
Do people have workshops/videos etc... on how people are effectively using Zotero beyond just adding references to word documents? I've tried grouping projects with folders, but this just leads to heaps of duplication across folders, Ive tried | Pretty much nothing if you're writing exclusively in LaTeX, when it comes to actual citing.
That said, I've got a library of over 5k papers so having them searchable by tags and other notes is exceptionally helpful. It's basically a personal database. | 66 | 48 |
CMV: Transgender definitions of a woman (or man) use circular reasoning so don’t make sense as a definition | I know trans posts are overdone here, but I think part of it is because the idea just doesn’t make sense to a lot of people on a fairly fundamental level and people are trying to square that.
I understand transgender people are in a lot of pain, confusion and distress and I earnestly hope they get the treatment they need.
The problem for me is that the proposed definitions just don’t make sense so it is hard for me to say someone is *actually* a man or a woman when they clearly just aren’t.
So to get to my main point, which is purely just about philosophy/linguistics, the general transgender ideology’s definition of a woman is ‘a person who identifies as a woman.’ But that doesn’t make sense? You cannot have the word in the definition too. It’s circular reasoning. What is the meaning of the ‘woman’ then that the person identifies as? I really want to be convinced of this as it’s the only hurdle I cannot get over.
(Also I will only be convinced by arguments that don’t bring up extremely rare exceptions like XXY people or someone born without a certain sexual organ. Categorisation (in language) is never 100% but in this case it applies to 99.999% of cases so is pretty tight. A few exceptions do not break the rule. It would be like saying ‘a human cannot be categorised as having one head because there are conjoined twins’.) | >my main point, which is purely just about philosophy/linguistics
It's a very surface level understanding of both philosophy and linguistics.
Linguisitically speaking, does the concept of "being transgender" exist in the spoken and written language? **Obviously it does.** It exists as much as being a Catholic, or being American, or being psychic, or being white, or being an aristocrat, or being cisgender.
Philosophically speaking, what does that mean? Well, not much. That the language creates subjective labels, and it is not really an essential revelation of "things that exist" in a material measurable sense, is a very basic observation. | 280 | 624 |
ELI5: why do our muscles require constant training to be strengthened instead of strengthening them once and having strong muscles forever? | Our bodies strive to be as efficient as possible in order to increase our likelihood of continued survival. Muscles, while being useful for motion, are quite expensive energy-wise, so the body only keeps enough muscle to meet the usual requirements for moving around.
Now if you regularly use your muscles to a degree that they get worn out a lot, such as by lifting heavier weights or running longer and farther, then the body builds those muscles bigger and stronger to meet the new requirements and prevent damage.
However, if you stop the additional exercise that built those muscles up, then the body starts breaking them back down because maintaining them costs too much energy and it doesn't seem to need the extra strength anymore. | 126 | 42 |
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CMV: Student assignments in introductory programming courses should always be full programs in normal languages, not "fill in the blank" snippets in toy languages. | I work as a computer science tutor and sometimes have students needing help with "fill in the blank" questions. The format is a website where students provide the implementation for a given function - say to sort an array - and then submit their code. The website reports back what the expected return value was and the received return value, and then either rejects or accepts the submission. Students never write complete programs - they only practice programming through the sort of fill-in-the-blank exercises I've mentioned above.
The last time this happened, it wasn't even in any normal language (Java, C, C++, C#, Visual Basic, JavaScript, PHP, etc...). The student couldn't name what language they used, so I guess it was a special "toy" language designed for intro cs students.
The problem is, I often have students who know absolutely no programming whatsoever. They don't know how to print "Hello, world!", they don't know how to declare a variable, never heard heard of a "loop" before, and so on. I basically have to start from scratch, spending our hour giving a lesson on introductory programming topics.
I normally do this by showing a complete example program that illustrates the building blocks of coding and having the student iteratively modify & run that, to explore first-hand how the building blocks work. It's not perfect, but I haven't found a better teaching approach - Socratic method question asking is useless when students know *nothing* at all, and writing lots of wordy notes just makes their eyes glaze over.
Unfortunately, I cannot do this when students have no way to just create a blank program to begin building & tinkering with, nor am I able to build example programs for students to illustrate concepts if they're using a course-specific toy language that no tutor would be familiar with.
Introductory programming courses following the format I've described above are just bad and do a woeful disservice to their students.
How can you CMV? Research showing that students who begin learning programming using a "toy" language instead of a normal one have a higher success rate would help. I'd also like to hear teachers' reasoning for not using tools that allow students to just make up their own programs from scratch, outside the context of answering assignment questions. | Algorithms and their teaching predates computer science by literally thousands of years. If a student truly is learning about algorithms (such as a sort), and trying to answer a question on the best way to achieve X, there's absolutely no reason this needs to be conducted in a programming language. Programming languages and algorithms are two different skills. Whilst they come together in programming software, they can be taught separately.
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I have a degree in 3D animation, and in our first year we studied the basics of a number of topics - modelling, texturing, life drawing, traditional animation techniques, character rigging etc. As time goes on and you get better versed in these different topics you can more easily overlap them, taking a single idea to its logical end point (a character design and story idea in your head --> an animated short film viewable on a screen).. If you want to teach someone character animation, you can either provide them with a modelled, rigged and skinned character and then start with the basics of actually teaching animation, or you can insist that they model, rig and skin their own character and only \*then\* begin to teach them the basics of animation. The former is preferable for a whole host of reasons, not least of which is that your modelling improves when you have experience of actually using the model to animate with.
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In other words, if you want your computer science students to begin learning about algorithms from day 1 (and surely this is vital), you need to allow for them to complete the work in something other than a programming language. This way they can learn both in parallel (and whatever else might be important). | 29 | 85 |
ELI5: Why is it that when my computer is doing something, the "time remaining" estimate fluctuates so much and is rarely accurate? | Determining accurately how long the task would take would take a while in itself, so the programmers estimate the length of the task using methods which may not be accurate but which don't risk significantly increasing the length of the actual task. Additionally, there may be circumstances which simply cannot be known. An example of that would be network speeds that are fluctuating. You obviously can't know during a download that half way through the network bandwidth is going to go to crap.
An example of a cheap but inaccurate estimate would be to use the number of files but not their sizes when copying files. If all the files are similar in size, then this is an acceptable estimate, but if you have lots of small files and a few very large ones, then the estimate is going to be way off. | 44 | 85 |
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How did our ancestors with insufficient vision survive? | This is a question I have bounced around in my head from time to time. I was born with poor vision (-3.75 in my left, -3.25 in my right), and recently underwent LASIK eye surgery. It went perfectly and I now have 20/20 vision.
Eyesight seems to be a trait inherited through genetics (Correct me if i'm wrong on this.), as it seems that people whose parents have poor eyesight are much more likely to end up wearing glasses/contacts/etc.
I imagine that not being able to see clearly ten feet in front of you would have been a severe disadvantage when in any kind of conflict, or even living in general.
My question(s):
How big a role did poor eyesight play while we were evolving from previous ancestors?
Why is it so common in our species despite being an obvious severe disadvantage, really no matter how you look it?
Do other species have issues with poor eyesight as much as humans do? (As in a dog born with poor eyes, not like a bat with naturally poor eyes.)
Edit: A couple of typos and clarity. | There is evidence suggesting that early humans had somewhat better vision than humans today. To answer your question bluntly, they didn't. Those with poor eyesight when hunting/gathering was the main food source probably died out. Since humans no longer rely so heavily on vision (an other senses, for that matter) and there are modern remedies for poor eyesight, it is much less of a factor in sexual selection. | 30 | 41 |
What will globalisation look like when wages are too high and comparative advantage is lost? | Comparative advantage in today's global economy is basically one countries wages are lower so stuff is built there and sold to countries with high waged worker what will happen when everyone is making a wage such that comparative advantage is lost will protectionist policies be put on to propel domestic industries like post great depression? | I think you're misunderstanding comparative advantage.
Comparative advantage is like this: Consider two countries that both make wine and cloth. Country A can make *both* wine and cloth more efficiently and more profitably than Country B. But Country A makes wine *much* better than Country B does while making cloth only a little better. So wine is just way more profitable for Country A than cloth is. In that case, Country A is better off buying cloth from Country B even though it's more expensive than making cloth themselves because overall, it's better to focus production on making and selling wine.
For Country A, switching production from wine to cloth would cost more than the cost difference between producing cloth and buying cloth. So even though Country B doesn't have any products that it makes better than Country A, it has a *comparative advantage* in producing cloth because it has a lower opportunity cost for not producing wine. | 128 | 62 |
ELI5: How much DNA do I actually share with other humans? | I know chimps and us share 98.5% of our DNA. However, what I don't get is how much DNA I'd share with any other odd human being on the planet. Like what's the scale? How many human-human DNA differences would it take to compare to a human-chimp difference? How similar actually are people of the same ethnicity? How different actually are people of different ethnicities? What's the real difference between how much DNA I share with my mother and how much DNA I share with a random person off the street? | The question you have to ask is what do you consider to be "different"?
Your DNA is made up of chromosomes. Those chromosomes are organized into genes. Your genes are then made up of base pairs.
The base pairs are the basic informational unit of DNA - much like a bit in computer memory. Each Gene is made up thousands to millions of base pairs.
Genes are the basic functional unit of DNA - much like a file on your computer. Each chromosome is made up of hundreds to a few thousand genes.
We're not entirely sure why chromosomes exist - they're kind of like a folder on your computer, if the folder just had a random assortment of shit in it rather than being organized in a coherent way.
If you look at your DNA on a chromosome level every person has the exact same chromosomes (except for people with serious genetic diseases).
On a gene level, 99.9% of your genes are identical to everyone else. The .1% of your genes that are different mostly control your visible physical attributes - like skin color. Even among that .1%, you're basically going to have the exact same genes are as everyone else from your race. So if you're ethnically Norwegian, chances are there is very little genetic variation between you and any other ethnically Norwegian person.
The base pair level is where you see the most variation, but even this is minor. So lets take our two Norwegian people. It may be that if we look at a particular 120,000 base pair long gene that both possess that there is one base pair in which there is a minor difference. Again to use the computer example - in a 120,000 bit long piece of code, you have one spot where one person has a "1" while the other has a "0". Other than that one spot, the other 119,999 base pairs in the gene are identical.
And if you were to look at the entire genome of those two Norwegians you might find one or two genes that are different. And of the genes that are the "same", there will be a hundred individual base pairs in those genes that are different - out of a total of around three billion base pairs.
The further ethnically you are from someone the more variation there will be. So if you take a Norwegian and an Australian Aboriginal, it may be that there are 200ish genes that are different. And of the genes that are the same, you may have tens of thousands of base pair differences.
But even this doesn't really give us a good idea of how different things are - because chances are that those 200 different genes are doing the same thing, just with slightly different proteins.
And when you look at the genes that are the same but have minor variations in their base pairs you're looking at meaningless differences. Maybe the Norwegian has the amino acid Isoleucine in the 453th position of a 900 amino acid long protein, while the Aboriginal has Leucine in that position instead. Does that actually change anything about the protein? Probably not.
The short of it is that the vast majority of your DNA is identical, with an almost insignificant handful of minor differences. Its just that your body is an incredibly complicated system and so even a tiny handful of minor differences can lead to huge variation in terms of how people look. | 43 | 45 |
CMV: Shifting to an 18-year US Supreme Court term would have substantial benefits that would outweigh the drawbacks | I think we would be better off if Supreme Court justices were nominated to 18-year terms rather than lifetime appointments. My vision for this would be that a seat would come up every other year, at the beginning of odd-numbered years. If a justice were to retire from their seat or die during their 18-year term, a new justice could be appointed to fill the remainder of their term.
The benefits I see of such an approach:
* Supreme Court nominations become slightly lower-stakes: Right now, when you nominate a justice in their 40s, they could conceivably serve on the bench for 40+ years before dying or retiring. This makes every nomination an apocalyptic event. I don't think that issue would go away entirely with 18-year terms, as that's still pretty long, but it would lessen the stakes somewhat.
* Supreme Court nominations become more predictable: We currently live in a world where we never know when a seat will come up to be filled; before Scalia's death, we had 4 justices who could decide to retire or come into ill-health at any moment (Breyer, Ginsburg, Kennedy, Scalia), raising the possibility that one president could potentially re-shape the judiciary dramatically if he/she got lucky. *Edit* as an added benefit, the phenomenon of SCOTUS justices deciding whether to "wait out" certain Presidents they don't like or retire under Presidents they do like would go away, which I think is a good thing.
* More democratic responsiveness in the Supreme Court: The prevailing philosophy on the Court can and does change over time, but it can take a very long time for that to happen with lifetime tenure, and the role luck plays in the timing of SCOTUS openings. With more predictable openings, if the public spends 10 years pushing for the court to move in one direction through their votes in elections, they can actually re-shape the Court. (I know this is a double-edged sword, because in theory the Court isn't always considered an institution that is supposed to be particularly democratically responsive).
* Removing SCOTUS battles from election cycles: If you could have the vacancies occur at the beginning of every odd-numbered year, they would be as far from the next election as possible, diminishing as far as possible the incentive to wait until an election before confirming a justice. And every time people went to the polls, they would know that their vote was directly impacting a SCOTUS nomination within the next few months.
* Less disincentive to nominating older judges: Not that nominating young judges is a *bad* thing, necessarily, but because of the stakes of lifetime appointments, there is a big incentive to look for really young justices rather than necessarily the best person to fill the role. In today's world, it's impossible to imagine nominating a justice who is 60 or 65 years old, because you could be giving up 10-15 years of their service on the back end relative to a justice who is 45-50. With an 18-year term, politicians would have more flexibility to choose slightly older and more experienced justices if they wished.
I know this would require a Constitutional amendment, and I know that will never happen, but I wanted to float it as at least a thought experiment. What am I missing? CMV!
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> *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 judiciary’s entire job is to be consistent. Although the position of the court is subject to change, it doesn’t very often. Because of one case in the 80’s, abortion is still around today, despite numerous attempts to change that.
Keeping a consistent bench is important to the stability of the United States government. A bench that changes too often can lead to reversals of opinions over and over again, which makes it very hard to argue a case based on previous outcomes.
Also, the Judiciary is what keeps the other two branches of government in check. Giving the president additional power over the courts will just make them more like the president.
The system we have today makes the courts a more fair environment. We have 4 generally conservative justices, and four generally liberal justices, with Justice Kennedy a swing vote between the two.
Keeping the Supreme Court like it is today helps preserve the balance that the government relies on.
Edit: Made a typo while trying to refer to Roe v. Wade, which was in fact in the early 70s. | 460 | 1,667 |
ELI5: Differences among Broiling, Roasting, and Baking | I just call all of those "sticking it into an oven" | I just learned about broiling recently, but let's talk about baking first.
When you bake, you cook the food by surrounding it with hot air. Because the hot air is all around the food, the food cooks from all the sides. If you use a toaster oven, you'll notice that the heating elements are not really on when you bake. They only turn on to keep the air at the temperature you set. Heat transfer occur from the hot air inside and the hot walls of the oven. In short, **baking happens from all directions via convection and radiation.**
According to JOY OF COOKING, roasting and baking are the same. I'd say the difference is that baking is for bread stuffs, and roasting is for meat stuffs.
When you broil something, you cook it from one direction with radiant heat. If you set your toaster oven to broil, only the top elements turn on. And they stay on, full strength, to brown your food. You're also supposed to put the food as close to the elements as possible and leave the door slightly open. It should be designed to stay slightly open for broiling. If you use your big oven, broiling happens beneath the heater elements in the smaller lower tray (not the bigger compartment). Same thing here with the door, you leave it slightly open. The result is similar to that of grilling. You get very nice browning on your food. (Excellent way of cooking meat if you don't want to grill outside). So broiling is **directional cooking mostly via radiant heat.**
**When broiling, if you don't leave the door open, you end up with a pseudo baking situation and you cook the other side of the food before you can brown the food on both sides. This is undesireable.*
Edit: word choice.
**Bonus generic broiling recipe:**
1. Preheat broiler.
1. Take meat and pat dry.
1. Add lots of seasoning of your choice.
1. Broil one side until browned.
1. Flip over and broil until brown.
1. Enjoy.
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How can both nuclear fission and fusion release energy? | I understand that nuclear fission releases energy such as a nuclear bomb. I also get that nuclear fusion such as how the sun power itself, also releases energy. How can two opposite processes both release energy? | Fission will occur if a nucleus can decrease its energy by splitting into smaller constituents, and fusion will occur if nuclei can reduce their energy by combining.
If a fission process releases energy, the fusion process obtained by running this in reverse does *not* release energy.
Likewise, if a fusion process releases energy, the fission process obtained by running this in reverse does *not* release energy.
The nuclei of heavier elements can release energy via fission, while the nuclei of light elements can release energy by fusing.
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ELI5: How gas masks' air filters can safely hold back toxic gasses but let air through? | The simplest filter out using very fine fabrics or composites, more complicated versions have layers of varying materials and activated charcoal, which acts like a magnet to particles and sucks them in, whilst fabric filters stop things like dust or spores getting through.
Air is small enough to be dragged through the gaps with the power of your lungs alone
Eventually the charcoal is ‘full’ or the fabric filter is clogged and the mask no longer effective.
There are different types of masks and this type cannot protect you against gasses that would kill you. For that you require an oxygen supply. | 33 | 20 |
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CMV: There’s nothing immoral about masturbating to someone’s Facebook/Instagram photos without their knowledge or consent | I just see it as a victimless crime. If no one ever finds out that you did it, then no harm is caused to anyone. No one ever needs to know and it’s not exactly a difficult thing to hide from others. I just don’t see what the problem is here - it seems to be yet another matter of policing what others do sexually in the privacy of their own home.
Obviously it’s a problem if you did it in public or something but otherwise I see no issues. And just so we’re clear, this goes for both genders. Either gender could masturbate to online photos and I have no problem with that.
Disclaimer: I do not do this myself because real porn is way way better. But I’ve heard of others doing it and the idea seems to bother some people. | The way you are describing morality seems to be from a Utilitarian perspective, e.g. if it does no harm, but there are other forms of morality out there.
From a Virtue Ethics perspective, you could make several arguments as to why masturbating to images of somebody without their consent is immoral. It could be argued that it demonstrates character out of line with a virtuous person, either in dehumanizing somebody or in acting without concern for others due to a knowledge you won't get caught.
From a deontological perspective, it is easy to imagine rules that would make such an action immoral. "Do not involve others in sexual activities without their consent" is an obvious moral rule that masturbating to somebody else arguably breaks. It potentially breaks the golden rule, as well, but that is a weaker argument.
Even from a Utilitarian perspective, there is potential harm from "victimless" acts. It is possible that masturbating to others leads to a change in mentality over time that is a net negative. There is ongoing research that suggests, at least for some people, porn addiction can be a severe negative and lead to problems both sexually and socially. It is possible that continually masturbating specifically to people one knows in real life has negative impacts through a similar mechanism. This is the kind of Utilitarian framework that would say that e.g. smoking is a morally negative act because it hurts you more than it benefits, so it's not necessarily intuitive, but the argument exists nonetheless | 26 | 23 |
Race vs ethnicities | Hi,
Would it be accurate to say that ethnicities are social constructs? It is common to see "race" be referred to as a social construct. Would it be appropriate to say the same thing about ethnicity?
Thanks | Rick Bonus defines ethnicity as a group formation on the basis of shared attributes, such as religion and other cultural practices, language, and nationality (Bonus 2015, p. 78). Race, on the other hand, is the illegitimate grouping of people together based mainly on skin color, along with facial structure, which does not accurately reflect anything about humans and can in many ways be circumstantial (for instance, the difference in facial appearance between Eastern Europeans and Western Europeans is minimal when people from both regions are raised with proper nutrition).
So race and ethnicity are both social constructs, but that doesn't mean that neither of them have any meaning or truth. Ethnicity is a cultural phenomena and in many cases can be dynamic, as opposed to the assumption of there being a fixed nature to race. Ethnicity could be described as an achieved status, as opposed to race being a (false) ascribed status.
​
Bonus, R. (2015). Ethnicity. In Schlund-Vials C., Võ L., & Wong K. (Eds.), *Keywords for Asian American Studies* (pp. 78-81). NYU Press. Retrieved February 22, 2020, from www.jstor.org/stable/j.ctt15r3zv2.25 | 37 | 43 |
Will filling up your car tank with gas when it's cold get you more gas when it gets warm and expands? | Someone told me this, and consumer reports https://bit.ly/3pZ8mel says it's negligible. I thought, if you added the same liquid volume of gas, even if it expands, doesnt the same total energy remain? | The energy contained in certain amount of fuel depends on the mass of the fuel. However, when you fill up your car, you're charged based on the volume.
So if the density of the fuel decreases because it expands due to higher temperatures, you need to pump a greater volume for the same amount of energy content. And that costs more.
However, this effect is ultimately negligible as the Consumer Reports article explains. Not only does fuel not expand terribly much at all, but fuel is usually stored in well insulated underground tanks and the temperature in those is very stable and barely fluctuates with changes in air temperature. If you've ever set foot into the same cave in summer and winter, you've noticed this effect. As soon as you enter the cave, the temperature of the air becomes largely detached from the outside temperature and remains pretty much constant.
Once the fuel is in the car, it will also expand and contract a bit with temperature fluctuations, but at this point it no longer matters as much. If the temperature goes up significantly, the fuel level in your tank will increase (slightly), but your engine will need to pump a (slightly) greater volume of fuel to get the same energy from it.
There are various temperature-related effects on fuel economy that do play an important role (tire performance, air resistance, engine warmup time), but the expansion of the fuel is not one of them. | 96 | 48 |
Why does ingesting lead cause poisoning and ingesting silver or gold does not? What is it about lead that makes it toxic? | Lead gets mistaken for other +2 ions such as iron or calcium. In the case of iron it can interfere with iron transport through binding to cysteine (lead has higher affinity for thiolates than iron), and heme synthesis (lead doesn't participate in the same electron transfer chemistry as iron). In the case of calcium, it interferes with neuron potentiation by binding tightly to an enzyme normally associated with calcium ion transport. Lead is usually ingested as an ion due to decomposition of pipes or as an inorganic salt component in paint (when leaded gasoline was still used, it was inhaled as lead oxide dust). Metallic lead isn't that toxic (otherwise folks with bullet's lodged in them would be in serious trouble) as the surface forms a passivating lead oxide layer that is stable at physiological pH.
Silver and gold are normally encounterd as metals. The do not dissolve to appreciable extent in the GI tract as they are non-reactive. Silver ions CAN lead to some interesting effect (including turning a person blue) if ingested in significant quantity. Gold ions actually can be toxic, but gold salts are almost never encountered outside of metal mining/refining. | 37 | 21 |
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ELI5: What exactly is radiation? Why is it dangerous? | Also, if someone could explain why nuclear reactions give off so much radiation, that would be great. | Radiation is defined as waves or particles emitted from an atom as it moves from a higher energy state to a lower energy state. This comes in several forms: heat, light, beta (+/-), alpha, gamma, electron, proton.
Radiation is dangerous because of the high energy with which the particles are emitted. These particles can penetrate the skin and enter the body, where they can damage cells and lead to cancer and other defects. | 31 | 80 |
CMV Suicide should be legal | I know I'm probably gonna get a lot of hate for this but realistically I don't fully understand why it isn't. None of us ever really chose to be alive yet by law we're required to maintain an existence we never asked for. I'm not suicidal, I'm just genuinely confused why there isn't more discussion about this. Suicide is such a touchy subject, and we've all been lead to believe that it's never the answer even though we don't even know how or why we are alive to start with. Does it make sense to make someone keep something they never wanted in the first place? I know it's more complicated than that, but I feel like there needs to be a real discussion about this.
Edit: I know there's loads of arguments to either side of this debate and honestly I hate arguing I just really felt like there needed to be a discussion about this. The media and all of us are so brain washed in a sense to fear death and things surrounding it rather than understand that its not all bad. Pretty much everyone I have met on this post has been pretty adamant against my points, but I'm honestly just glad we can talk about it. I hope this post helps some people understand that this doesn't neccecary have to be a one sided issue. Thank you guys :) | In many cases, depression can be effectively treated and people can be brought back to the state of mind they were in prior to their depressive episode. In many cases of mental illness, suicide should stay illegal, however, in cases where the afflicted individual doesn’t respond to medication or therapy, the individual should be allowed to end their own life. Same applies for physical illness. If one is terminally ill and wants to put their life to an end before they succumb to their disease, they should be entitled to do so. | 608 | 1,568 |
CMV: Hand washing facilities should be placed outside of bathrooms rather than inside. | Washing your hands after going to the toilet is obviously a good thing to do. The problem, as I see it, is that this relies on everyone washing their hands (which we know isn’t the case). If there is an inward opening door, you have to make contact with the handle which is touched by everyone else.
Also, unless the stalls are completely sealed, it seems that fecal particles can disperse through a room, meaning that the taps(faucets) and any other surfaces are compromised.
It makes more sense to me that we wash our hands once we leave the bathroom so that we sanitise once we no longer have to contact shared handles or objects that share a space with toilets. It would incentivise the non-washers to wash because it’s more likely the handle will be compromised if no one has washed their hands before exit.
The ideal solution, in my opinion, would be to have hand washing facilities both inside and out as we may also use the sinks and mirrors inside the bathroom to shave, apply make up and have the option to double wash.
I’m struggling to find any downside outside of the financial and architectural inconvenience. I don’t really think they are significant enough to prohibit this, as we accept these for other things when the inconvenience is outweighed by the benefit.
Change my view! | Problems you bring up are valid, but there’s already good solutions for them. Automatic sinks, soap, and towel dispensers, and doors that you can push outward without touching a handle, or bathroom designs that have a small bended hallway for privacy but no door.
Sinks should be kept inside because of the potential they have to get water everywhere, and for the convenience of keeping all the garbage in one place. They’re also pretty loud, if you consider them in an otherwise quiet place like a fancy restaurant or something. In places where there are many sinks needed, it would take up much more space and require a whole other room to keep them in which ruins the purpose anyway | 718 | 3,787 |
ELI5 what is pre-workout and how does it work? | Preworkouts are combinations of chemicals intended to do a few things (depending on what's in them).
1. Make you feel more energetic. Thinks like caffeine or ephedrine are usually used for this.
2. Ensure you get the most out of your workout. Things like creatine and beta-alanine.
3. Ensure your body has the things it needs during a workout. Things like sugar and various amino acids are used for this.
In general, pre workouts DO help, but the effect is a lot smaller than people would like you to believe. In most cases you can get most of the effects with a proper diet and a cup of coffee. | 90 | 59 |
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In your field, how would you design the ultimate digital paper-reading assistant? | For example, in computer science it might be helpful to have a tool that will keep track of variable name definitions in equations (i.e., highlight all instances of the variable and give definition upon hovering). That way, you don't have to keep searching backwards for what *z* represents.
I'm curious what the most annoying part of papers in other fields are. We have so many cool tech tools at our disposal but reading PDFs of papers is still pretty non-interactive. | In biology, I'd love a tool that fetches the relevant text when the materials and methods says "X was performed as previously described [cites old article]". We too frequently have to jump back through a decade of papers to find small but important methodological details. It would be even better if more journals actually enforced writing clear methods sections in the first place, and stop including them in word counts... | 24 | 37 |
What does Nietzsche mean when he says "only the human being is a burden to himself! This is because he lugs too much that is foreign to him"? | ...but only the human being is a burden to himself! This is because he lugs too much that is foreign to him. Like a camel he kneels down and allows himself to be well burdened.
Specifically, the reason he gives, after "this is because..."
Edit: forgot to mention, this is from Thus Spoke Zarathustra. | This is an excript from one of the first stories from Thus Spoke Zarathustra, where he describes what path the mind must take to overcome itself.
First when he sees the dragon (representing religion and other moral/value system), with his shiny flakes (representing individual values themselves), he becomes overwhelmed by dragon'a significance and his own insignificance, so he burdens himself with his values.
He takes pride in this achievement, but he is burdened greatly by it. That's where the "he lugs to much what is foreign to him" makes sense, since the dragon's values are foreign to him, and not of his own creation.
At some point the burdens becomes to great to carry, and the transformation into a lion must occur. The mind of a lion says "No" to every "You shalt" from the dragon. He destroyes the beliefs and values of the dragon, until there are none left.
Then another transformation occurs, not into the child. With genuine curiosity, openmindedness and such, the child creates his own values.
Or so spoke Zarathustra. | 42 | 43 |
ELI5: Why do I get lightheaded when I stretch my body? | Even stretches where my head doesn't go below my waist, like having one leg up on a beam and leaning forward, I always get lightheaded and have to stop. Why is that? | Stretching tells your body to put more blood in a certain area. This decreases the pressure in other parts, like your head. Imagine your body is a long, semi-inflated balloon that's almost completely deflated at one end. When the balloon sends some of the air to the deflated portion, the rest of the balloon bets slightly less inflated as a result.
The lightheadedness is caused by a slight drop in blood pressure. Eventually, your brain gets used to it and you get back to normal thinking abilities.
IANADoctor, so there's probably a more in-depth explanation, but this is ELI5. | 271 | 531 |
[Blade Runner] What's going on in the off-world colonies? Why are they so violent? | By 2019, humanity has expanded into intergalactic space. [Most of what we know about the off-world colonies is given in the form of the job descriptions of Replicants during Deckard's meeting with Harry Bryant.](https://www.youtube.com/watch?v=kGy6ZRAFW_Y)
**Leon** An ammunition loader on intergalactic runs. He can lift 400 pound atomic loads all day and night. The only way you can hurt him is to kill him.
**Roy Batty** Combat model. Optimum self-sufficiency.
**Zhora** Trained for an off-world kick-murder squad. The computer display under Zhora's readout lists her job as political assassination.
**Pris** A basic pleasure model. The standard item for military clubs in the outer colonies.
Finally, during Deckard's confrontation with Roy Batty, Batty talks about attack ships on fire off the shoulder of Orion. Even if these are not Roy Batty's memories, if he was created like Rachael, then they're someone's original memories.
Humanity masters extreme faster-than-light travel and expands into intergalactic space in a remarkably short period of time. Regardless of what political factions exist on Earth at the time, one would figure that with entire galaxies opening up to humanity, there would be boundless space on countless worlds and no one would have to fight over anything. Even if most Replicants are peaceful and only a small minority of military replicants rebel and come to Earth, there's still a minority of Replicants that are very violent, trained for things like mass ammunition loading, combat, political assassination, and have memories, or copies of memories, of combat spaceships in battle. Why is the future this violent? | As the colonies become more and more self-sufficient, they begin to feel like they should be free to forge their own destiny separate from Earth. Earth, relying on their resources to keep things going, have to keep them in line and that sometimes takes anything from covert ops to full military action. | 102 | 178 |
What does it mean if "the Sun releases 5 million tons of pure energy every second"? | This is a quote lifted directly from a text-book designed to develop teachers' subject knowledge, and seems a bit odd to me. I'm assuming they're talking about tonnes meaning equivalence to tonnes of crude oil but that seems like an abysmal unit to be using, especially without explanation. | By Einstein's famous relation E=mc^2 matter and energy can be interchanged. When hydrogen fuses into helium in the core of the Sun, the total mass of the products is less than the mass of the hydrogen atoms that you started with, due to nuclear effects. The extra mass is "lost" as energy, and because c^2 is such a large number (9 x 10^(16)) that's a lot of energy. That's why nuclear power is so much more potent than chemical power - you're converting a small amount of mass effectively directly into energy. | 13 | 22 |
ELI5: How is Jurassic Park's CGI able to hold up and even beat movies that are released in this century, even though their budget was $63 mil? | JP used a combination of CGI and "practical" effects, meaning real effects. A LOT of what you see is puppets. Most of its CGI is just the combination of the two shots or enhancements to them.
Modern CGI doesn't quite have the same effect. One of the major problems is lighting. Animators never seem to get it quite right and so you can more easily tell it's CGI. With a practical effect, they can better match lighting, etc. | 608 | 727 |
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ELI5 why are so many Muslims pissed off with 'the west'? | I take this huge world shaping fact for granted without really wondering why...did we do something terrible? | Many factors:
Relations between Islamic countries and the U.S. were profoundly affected by the west's cold war on communism.
The U.S. traditionally fought the growth of a pan-Arab nationalism in the region.
The U.S. traditionally supported Fundamentalist religious movements as an additional mechanism to fragment the Arab world.
Petro-dollars brought enormous wealth to many Muslim countries creating vast economic schisms and leaders that were autocratic, unelected, and not particularly accountable to public opinion.
Millions of Palestinian refugees have been created as a result of the 1948 and 1967 wars in Palestine.
Governments in the region tended to invest in major infrastructure projects, but not in education improvements or activities that would bring economic opportunities to the people.
In many Arab/Muslim countries, the youth suffer immense frustration, created by high unemployment rates, poverty, lack of education, and lack of hope.
Many Muslims object to American culture.
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[The Matrix] What is the purpose of The Oracle ? Isn't it harmful to the Matrix ? | It's important to note that while the Machines are all part of the same system, they are also individuals. Including programs. With their own sentience to boot. They are allowed to have different opinions and philosophies, and some of them like the Oracle, Smith, or The Merovingian definitely stand in opposition to the whole.
The Oracle's job was to guide the One and get him started on his journey. Just give him confidence through prophecy and get him going on the right path. The current Oracle, however, went past that deliberately set multiple humans (Trinity and Morpheus) as well as the One on special paths that would end up disrupting the Matrix as a whole, because she wanted it to end. | 30 | 46 |
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ELI5: The difference between speaking from the throat and speaking from the diaphragm. | As best I understand it: The best way to project ones voice and, ultimately, orate is to ‘speak from the diaphragm’.
How would I know if I was? Isn’t it just about vocal cords? | Here's an easy way to tell the difference.
Try speaking to yourself in a very low volume, mumble like you're almost humming. If you pay attention, you'll notice a sensation like a vibration coming from behind your jaw.
Now, take a deep breath, open your mouth widely, and yell a sound while exhaling forcefully, like "ha" or "hey", as if you want someone far away to hear you in a large crowded area. You may notice that your skull seems to be vibrating less than before. You may also have the sensation that the voice came from deeper within you, instead of your general throat area.
The first one was you speaking from the throat. The second was speaking from the diaphragm. | 11 | 16 |
ELI5: What is the paradox of tolerance? | I keep hearing this a lot and I don't get it. For instance: Say an argument breaks out between two sides, when a third party points out that both sides are being incivil and they need to chill out so they can lead to a civil compromise or conclusion, they get dismissed because of this paradox.
What do they mean? | "Tolerance" as a ideal, would be to allow each side to speak their peace and have an equal chance to be heard. The idea behind this is that, by being tolerant of all beliefs, all beliefs can flourish.
However, the issue is that not all beliefs allow other beliefs to coexist, or allow tolerance. So by tolerating an intolerant belief, you are actually harming other beliefs. If one belief system espouse the destruction of followers of another belief system, those people will either be destroyed or will be silenced, either of their own volition to avoid being targeted or through harassment/censorship. This is the paradox of tolerance; by tolerating all beliefs, you may open yourself up to an intolerant belief system reducing the overall tolerance of society.
The solution to the paradox of tolerance is to not have unlimited tolerance. When a belief system advocates for the destruction of another, it loses the umbrella shield of tolerance. This puts them into a dilemma: change their views to be tolerant of others (ideal), or exit from this society (unfortunate, but maybe necessary). | 95 | 39 |
ELI5: Why is it that when men ejaculate they do so in "pumps", but when they urinate, its in a constant stream? | Generally different mechanisms and muscles. Urine is stored in the bladder, which is basically a big muscular bag, and more or less just needs to be released.
Ejaculation is a more complex process that includes using the muscles of the pelvic floor to drive the semen out. Basically, the semen is stored in tubes that connect to the urinary duct, and then these muscles propel it out (see a textbook for details).
Interestingly, you can also use these same muscles to propel out remaining urine in the urinary duct.
As for *why* this is the case, it simply makes reproduction easier by "firing" semen toward the womb. This is done most efficiently in waves of muscle contraction. This is not really a requirement for urination. | 30 | 29 |
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I believe that combat between two consenting adults, up to and including dueling, should be legal and regulated. CMV. | I believe that if two people choose to engage in a fight, they should be allowed to do so. Ideally, it would be regulated in such a way that either participant could reasonably withdraw their consent, and bystanders were not placed at risk. I would imagine this including an agreed upon arrangement, stipulating the limits of the conflict, and an official (possibly a police officer) who would ensure that the limits are observed. Should either party violate the agreements, or place a bystander at risk, they would be held criminally liable.
The saying generally goes, "violence is not the answer," but the fact is that often times it is AN answer, and statistically, it's one of the most commonly used. | Here is a scenario where what you are describing legalizes murder and kidnapping.
3 people want 1 person dead (not an unlikely scenario). These 3 people kidnap and take the 1 person out to the woods and kill him. Then they report that 1 of the 3 was dueling him, while each of the other two were the dueler's respective seconds.
They testify that it was an agreeable duel and the man who died did so under his established guidelines. He isn't alive to tell the truth.
| 21 | 47 |
I think adding fluoride to public water is good CMV | My husband thinks water fluoridation is bad but I think it's good since it keeps our teeth healthy and clean.
I've been drinking fluoridated water my whole life and i've always had healthy teeth.
Fluoride, is just a mineral and is a naturally occurring substances, how can it be harmful if it's naturally occurring?
Webmd says fluoride prevents gingivitis, and decreases the amount of cavities you'll get.
This website http://www.quackwatch.com/03HealthPromotion/fluoride.html says it doesn't cause cancer.
This page says water fluoridation doesn't lower people's IQs http://www.kansas.com/2012/09/11/2485561/harvard-scientists-data-on-fluoride.html
If someone doesn't want fluoride in their water they can always just buy a water filter. Is that really so hard? | > Fluoride, is just a mineral and is a naturally occurring substances, how can it be harmful if it's naturally occurring?
Fluoride is fairly safe, but this is just a bad argument. Arsenic is naturally occurring, its the reason that cherry trees are kept away from livestock. In fact, fluoride is highly reactive and literally changes the chemical composition of your teeth merely by exposure. It's not some kind of vitamin that we need to make healthy teeth.
A note from personal experience too much fluoride is very bad for you. People living in areas with large amounts of natural fluoride have to filter it out. | 32 | 51 |
Genetically Speaking, how many possible people are there? (or how many possible combinations of genes are still "human") | Presumably there would be a lot, but I was wondering what the likelihood of someone having identical DNA to someone who isn't their identical twin. (For example, is it possible for somebody to be born today who is a genetic duplicate of Ghengis Khan or Che Guevara?) | The human genome has about 4 billion base pairs, of which about 2% are coding. With 80 million things each taking four possible values, the number of combinations is about 10^10^53 possibilities. That's about the square root of googolplex. Obviously this answer is an approximation and ignore other aspects of genetics. | 37 | 80 |
ELI5: Machiavellianism | Machiavelli is best known, and the term which now bears his name comes from, a book he wrote called *The Prince*. In it he explains clearly to the rulers of his day how a prince, the ruler of a city-state, should act. He gives advice on a range of topics, but in general it all comes down to a few key rules.
First: it isn't important what you do, only how you are seen. A prince must be believed to be trustworthy, faithful, and just. He need not actually be any of those. In fact he should not be.
Which brings us to the second rule: do whatever you must whenever you must. A prince takes whatever course of action best maintains or increases his power. If you see an opportunity you take it, if something is a threat eliminate it.
Third: your subjects are both the greatest power and greatest threat you have. Treat them as such. You must ensure that they will never try to remove you and that they will obey you. It is best to be both feared and loved, but if you must choose one be feared. Feared but not hated. If people hate you they will remove you, if they fear you they will obey you. To ensure fear but not hatred follow the same rule for those you must remove at home as you follow for those you must remove in war.
Fourth: both in war and at home destroy your enemies completely. Those you must destroy will hate you and seek revenge if they can. Do not leave them able to. When you finish they should have no capacity to harm you left. But do not damage in any way others, you will make new enemies that way.
Fifth: never trust others. Do not trust your allies as a state. Do not trust mercenaries as an army. Do not trust advisers as a man. Everyone has their own agenda, it is never the same as yours. Know what they want and you can use them. Never believe that they want what you want.
Sixth: above all else never get involved in a land war in Asia. | 120 | 126 |
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CMV: International migration restrictions are morally wrong and ineffective. | Speaking as a liberal Canadian, I have a few reasons morally why restriction of immigrants is wrong (with the exception of screening criminals).
* So, from a moral perspective mobility is a basic human right that should be an option for everyone. In the past everyone had access to it and has only changed as of recently. The current international migration system creates global inequalities - social, political and economic. Since citizens of each state have an obligation to change this situation and improve it. In order to do this we must allow more people to migrate in order to improve their life chances.
* People have become separated from their families and loved ones because of our restrictions on migration. Because of the competitive nature of migration, some people may be approved into a country, but their loved ones may not.
**Politically and economically speaking**;
* If we have more open door policies, we will see an increase in bargaining power of individuals in their negotiations with different faces of sovereign power. This will then make captives of their states allow lousy regimes to resist reforms. An example of this is, Apartheid Era south Africa.
* Increased migration can spur political development by making states work harder to keep their people from leaving. This will essentially act more like firms trying to protect consumer base. A truly competitive global market for labor would lead to greater competition among countries and likely improve political outcomes for their citizens.
* Furthermore, evidence suggests that migration improves the economic conditions of both receiving and sending countries. However, in short term, benefits and costs are unevenly dispersed. Migration increases competitions among workers, especially in sectors where there is high supply. In longer term, increase size domestic markets and new sources of revenue may offset these cost.
* More mobility can lead to renewed economic development in poorer neighborhoods and will provide new revenue to assist and maintain social policies (pension system, Healthcare programs in countries with ageing populations).
* In addition, migration would also reduce costs of border enforcement.In conclusion, free mobility will be beneficial economically and politically to both all counties involved.
Please leave the footnote below the following line, but remember to delete this sentence by replacing it with the body of your post. Thank you!
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[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)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 1) The primary purpose of a government is to protect its citizenry. This includes militarily, economically, and from criminals.
2) Freely traveling across borders or "mobility" as you put it is not a basic human right. People have never historically had free range of travel. For most of human history you seldom traveled more than 20 miles from home. | 28 | 29 |
[Chemistry] Why is it unlikely that symmetrical molecules can turn plane-polarized light? | If you had *one* molecule, and *one* plane-polarized photon, and an extremely sensitive detector (way more sensitive than is probably physically possible), you might see that photon's plane of polarization rotated by an interaction with an achiral molecule.
The thing is though, there are lots of molecules and lots of photons, leading to lots of interactions. It's not that an achiral molecule can't affect the light in that way - it's just that there is no bias towards any particular direction. Each interaction is equally likely to rotate a photon's polarization plane clockwise or counterclockwise, so averaged out over many interactions you end up with no net rotation. | 20 | 40 |
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Eli5:What prevents our bodies to get rid of excess food/calories that are not necessary, and instead turns it into fat? | Through most of human history and that of our evolutionary ancestry, storing energy was beneficial to survival since food was more difficult to come by. As a result, we evolved to store excess calories for future energy. But now we live in a society of abundance where it is not as useful. | 104 | 57 |
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How long does an arrangement of particles have to be together to be considered a new element? | What is the minimum half-life of an element? | The question is mostly about how long does a system need to be bound to be considered a new element. Well new elements are super heavy. They decay by alpha decay or fission. Typically you would define a new isotope by whether or not it is bound. So the time scales for how long it is bound depend on the decay mode. The shortest time scales would be around 10^-22 seconds. Of course new elements last longer than that right now. Elements around 118 decay in milliseconds, which is much easier to measure. | 11 | 41 |
ELI5: Why do you "black out" when you've had too much to drink? | People have 2 different types of basic memory-- Short Term and Long Term. Short term memories are processed and stored in the brain for only a few minutes. However, short term memories that are deemed by your brain to be "significant" are later converted into your long-term memory storage.
In excess, alcohol somehow blocks the brain's ability to convert short term memories into long term ones. Therefore you can still operate on a short term memory level-- you can still have conversations, interactions, and function on short term memory-- but since due to alcohol these short term memories cannot be successfully converted into long term memories, the next day you may have no recollection of the previous night. | 21 | 19 |
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ELI5: how do they decide the name and generic name of medications? | When chemists name chemicals it is not as much a name as a description of it using Greek words. This is also why some chemicals can have multiple names as there are multiple ways of describing a chemical. The problem with these names is that they can not be trademarked because it is just a description of the chemical. They might also not be as easy to market. So drug companies go to their marketing department and ask them to come up with a better name. It may sometimes be similar to the chemical name but does not have to be. The designers in the marketing department need to come up with a name which sound good and distinctive to the group of people they try to market towards. | 21 | 16 |
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"If the assumptions imposed in an economic theory are unrealistic, then the theory may nonetheless predict better than any alternative theory." | I don't quite understand this statement, I was wondering if someone could provide an example of what an "unrealistic assumption" might be within a given economic theory/model. | common sense and classical economic theory predicts that if two people are similar (same gender, age, schooling, skills, etc), they should be paid similarly. However, that is not the case when we look at real data.
People like Mortensen and Pissarides showed that in their economic setting, one of the major causes of this was what they called search frictions, that is, people wanting jobs and firms wanting people don't meet efficiently. This causes wage dispersion and unemployment.
If you look at their models' assumptions, we have standard stuff like utility maximizing agents, to some more out there assumptions like Nash bargaining behaviour, random job destruction, exogenous wage determination etc that makes the models more tractable. Obviously none of these assumptions actually happen in the real world. People are not thinking about Nash equilibria, wage determination is very complex, etc. However, (some of) the predictions of the model are on point and consistent with what happens in life. How come such an 'absurd' and simple model can make predictions so consistent and reasonable? That speaks to the value of abstraction and mathematical modeling.
If you tried to come up with an unemployment model that tried to have no assumptions and tried to have every feature of the real world in it, it probably would be of no more value than a much simple one, and at a much higher cost. | 12 | 16 |
ELI5: if an unconscious person is operated upon by a hospital, is there an enforceable contract between them, even in the absence of an express agreement? Specifically, what kind of a legal obligation is that patent under, if not a contractual one? | Medical ethics, backed by law in English speaking countries, require that doctors to do whatever is immediately necessary to preserve a patient's 'life and limb'. (Within the facilities available to them and without putting themselves at risk.) So if you arrive at a hospital unconscious, they will do what they can to reverse that.
Who ends up paying for it in the end depends on where you are and what the health service is like. Here in NZ, the state pays. Even if the patient is a stupid tourist with no travel insurance who just fell off a mountain.
But if the unconscious person is in the USA, he or she has just inadvertantly handed over all their assets to the hospital. You guys need a single payer system so badly ... | 35 | 27 |
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[Wall-E] How does Wall-E determine which objects are valuable/important? | I mean, he's a robot. AI and stuff... is it just thousands of years of learning what humans had certain affinities for and sorting the items based on that? I mean, as far as collecting spare parts for himself, that's fundamentally logical, but as for all the little tchotchkes he was collecting... why? And beyond that, how did he decide what was worth collecting? | He seems to have built-in routines for collecting spare parts, storing them in a home base, cleaning or repairing the parts, and using them to perform self-repair. But collecting random things he finds pretty or interesting and watching films and other recordings of humans? That's straight-up anomalous behavior for a Wall-E unit. Still, it's interesting how the hard-coded behavior almost directly developed into the emergent behavior.
It's likely a result of adaptive behavior routines to help robots adjust to foreign environments. In Wall-E's case, his routines are running amok and he's more or less self-aware at this point. It's meant to make robots operate longer and more efficiently the older they get, but it can lead to unpredictable behavior like collecting relics that look pretty, or putting the ship on lockdown and lying to the captain, or staging a mutiny. | 291 | 349 |
ELI5:How unique is each persons set of capillaries, veins, and arteries compared to everyone else? | While I understand the general shape will (hopefully) be the same, how much variance is there in the path of veins and where capillaries branch off and meet back up? | Not only are your capillaries unique, they're also constantly changing. Angiogenesis is the process whereby the body creates blood vessels.
As for other vessels, major vessels will be generally in the same areas (jugular vein, femoral artery, etc), but the smaller ones may have some variation from person to person regarding their exact location. The general layout and vacinity will be the same, but the exact path will vary slightly.
Just hold your left hand next to someone elses and look at the differences in the veins on the backs of your hands. | 29 | 86 |
ELI5: How do trees get water to their top portions without any sort of pump (like a heart) | Vertical plants generally have vascular (transport) tissues called xylem which carry water up from the roots to the leaves. Wood is one of these transport tissues. And as everybody mentioned, these work through capillary action, which sucks the water up like a straw. This is due in part to water itself. Because of something called hydrogen bonding, water molecules are actually really attracted to each other, and they want to stick together. If one water molecule evaporates through a leaf, the next one says "No, don't go!" and follows after it. This causes the next one to reach out, and the next, and the next, all the way down to the roots in a process called transpiration.
**TL;DR: a one-way road to the top, and water molecules having the world's largest open relationship with themselves.** | 47 | 72 |
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Mastering out after 4 years PhD (US)? | Hello everyone,
Plant biologist here doing a PhD in USA. Will try to keep this short, but any insight or comments are greatly appreciated.
I am currently in the beginning of my 4th year of my PhD program (+ 8 months of internship in the same lab for a total of almost 5 years of research). All my projects so far have been fishing projects, and all of them have failed (results have not been exactly good enough to pursue our hypothesis). I have met some grad students from my lab that have been into the PhD program for about 7 years when it should take 4-5, and I am worried I am on the same track, which is something I really don't want since I feel very burned out and don't see my CV getting super good even with the extra years. My PI have promised me to work on a paper I have been working on for 2 years, but requires some serious commitment from his part to be publishable. However, he is always busy and never do any substantial progress. So, at this point, I feel like I have 5 years of research experience, no papers, no projects for a good thesis that could allow me to graduate soon-ish... Which are my options? I am thinking to master out with a "bad" or "weak" thesis but to be honest the thought of the time I have put into this makes me feel awful. I am currently the only grad student in the lab and even then my PI prefers to give me projects that are slow, but he doesn't really work on the advancement of my career. He is a good person but definitively not the most interested PI in his students' career. My career goal is pretty unclear at this point since I have not work experience outside of academia because I went directly from undergrad to industry. Nevertheless, I am almost certain I don't wanna pursue academia anymore, which opens a whole another conversation.
What would you do in my case? Master out? Keep going for a PhD even if it takes double the time I have already put into it + mental health cost?
Thank you all for reading. | Master out. Have a heart to heart with your PI about publishing one good paper.
It may be neither of your faults, but if you don't know what you want to do for your carer, your PI probably isn't in a good place to help you either. They may think they are helping you by giving you all these different opportunities to do different research projects. Talk with them about your needs to not explore, not dillydally, and just get one good paper together for publication. This will set you up for the best possible success regardless of your future decisions. | 67 | 65 |
[Star Wars] How casual is interstellar travel? | Your average civilian on an average planet in the Republic, how likely do you think it is they have visited another planet? Trying to make a real-world analogy, would visiting another star system be seen like visiting another country, i.e. your average civilian only does it once a year or so? | > would visiting another star system be seen like visiting another country, i.e. your average civilian only does it once a year or so?
That's a good analogy for it, but it's not accessible to the average citizen. To be specific, it's more like taking a plane. Middle class citizens would be able to afford going on trips once a year, though the ticket for the trip is only part of the cost. Poor people might have to save for quite a while, depending on the planet and rich people have their own personal ships. | 43 | 25 |
ELI5:How to Kurt Godel manage to "break" mathematics? | Godel did not "break" mathematics, but rather he proved that there existed limitations to the degree we could root complex mathematics in basic, formal logic.
Philosophers and mathematicians wanted to devise a system where you could take a few basic axioms (unproved statements accepted as generally true), some rules of inference, and then construct every possible mathematical statement that was true.
There are two qualities we want in a system:
1. Consistency - The system never produces a result that is false (for example: 2+2=5)
2. Completeness - If something is true, then our system is capable of producing it as a result (for example: 2+2=4 is true, so we want our system to be able to prove that).
Philosophers and mathematicians spent a great deal of effort trying to develop such systems, until Godel proved that you cannot have a system that is both consistent or complete. A fully consistent system won't be complete (it won't be able to prove everything that is true) and a fully complete system won't be consistent (the system will "prove" things that are false).
Needless to say, it basically shelved such efforts to ground math in pure logic, and any logical system of mathematics has to settle for being either incomplete or inconsistent. | 23 | 15 |
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ELI5: What happens to a mortgage or similar loan if the person getting loaned to dies? | When someone dies, their assets and liabilities become part of their estate. This normally includes the house (as an asset), life insurance proceeds (another asset), and some types of loans (liabilities). The assets can be used to pay liabilities and remaining assets are given to heirs. Paying off the mortgage after the death of the family breadwinner is one of the big reasons people purchase life insurance. | 19 | 35 |
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ELI5: How will the upcoming Russia/US space station remain in lunar orbit without being captured by Earth's gravity? | It's all in the title. How do you keep an object (like a space station) orbitting the moon without that object being captured, and pulled in, by Earth's gravity without using an unreasonable amount of fuel? If Earth's gravity is strong enough to hold the moon in its orbit (less the small distance away from the Earth it moves each year) does it not stand to reason that the Earth's gravity will hold something much, much smaller? | The force of gravity is inversely proportional to the distance squared between the two things. By having something much closer to the moon than the Earth, the moon will have a greater pull in spite of being less massive. Much like why satellites can orbit the Earth in spite of the sun being significantly more massive. | 31 | 20 |
Do some people deserve to die ? Any books about death penalty, or righteous killing ? | Ok to elaborate, i was talking with a christian and i told her that whether she accept it or not, god is a killer. And that the argument "God doesn't kill people, people are killing themselves by disobeying" is borderline dangerous when you think about it, like some kind of weird religious newspeak.
And then she told me , ok god kills, but don't you think people deserve to die ?
I said that i had no answer, and that i will think on the matter. | There are loads of books but your topic is a bit wide.
There are debates of the death penalty and the proper aim of punishment, there are discussions of self-defense, accounts of just war, discussions about the importance of intentions, accidents, luck, culpability, acts/omissions, balancing competing outcomes, etc. | 54 | 110 |
ELI5: What do the blood pressure numbers mean and how do they relate to each other? | Basically, I've always been really healthy, went to the doctor, got my BP (104/68) and was told it's really healthy.
Then I said (to my Mom, an RN) "would it be better to be 104/80 or 104/60" and she just looked at me like I was crazy, then told me 104/60. Then I said, "but would it be better to be 100/72 or 104/68?" And she was just done with me at that point and I just don't understand what these numbers mean and the internet is too advanced for me. | The top number is referred to as the systolic blood pressure, and the number is a measure of the pressure of blood against the walls of your arteries as your ventricles (lower two chambers of the heart) push blood throughout the body.
The bottom number is referred to as the diastolic blood pressure, and the number is a measure of the pressure of blood against the walls of your arteries as your heart relaxes and the ventricles fill with blood. This is also the period where the heart relaxes in between heart beats.
Generally speaking, a systolic pressure higher than 120 is a problem, whereas a diastolic pressure higher than 80 is a problem. So there isn't really an issue if you are below those values except if they get too low (such as 90/60 or below). | 138 | 268 |
ELI5 How is basic universal income different than unconditional welfare? | At the end of the day, wouldn't basic income still just be the government giving away free money? | They are similar concepts designed to solve similar problems, but there are subtle differences.
Basically, welfare only goes to the needy. You generally have to apply for it. Basic universal income goes to everybody, rich and poor, whether or not you've applied for it.
This impacts ideal tax policy at the lower income levels while creating certain buts of bureaucracy and eliminating others. It also means the amount given to citizens goes up, so a corresponding tax has to be raised or deficits have to be incurred. Since taxation is almost always expressed as percentages and the basic income is expressed as a defined amount, this would mean that tax burden is shifted up from the lower middle-class to the upper-middle class, flattening their post-tax earnings somewhat.
The big theoretical benefit, however, is that it would eliminate some of the worst aspects welfare. Welfare incentivizes people to work under the table (pay no taxes and usually work bad jobs), disincentives them to find a permanent job or part-time job (they can lose welfare benefits and have to work a lot more to earn only a little more), and makes them feel like terrible people when they have to wait in line and beg a bureaucrat for money to survive. A basic income has none of these problems, but it comes at a higher cost to the budget. | 25 | 30 |
ELI5: If I throw a rock straight up into the air, for how long exactly does it stay at 0 mph before it falls down again? | Is it the same for any mass?
This is a bit of a weird one, but somehow I **really** want to know this. | In practice it depends on how accurate your measurement of speed is. That is, how many digits you are willing to consider.
Mathematically you can work it out pretty easily. The answer is zero seconds. The top of a parabola is one point only, it has no extent. | 36 | 28 |
How do scientists decipher a language with no known speakers? | How do scientists decipher ancient languages (like a carving, insription, scripture or whatever) with no known speakers? Can they figure out the sounds would relate to each visual symbol? What if there aren't any languages that were verbally or visually similar (as if none evolved into or from it and it was "unique")? What are the main problems scientists face while trying to decipher an unknown language? | Sometimes you can find a document in both an unknown and known language. But often you have to resort to cribs (phrases that you know will appear in the text). For example you know a text was issued by a king, you can guess that the word king and the king's name appear. It's basically a known plaintext attack.
Sounds? Not sure how they'd figure that out.
| 14 | 36 |
So, where are all the beneficial infectious diseases? | As far as I can see, most infectious diseases work somewhat along these lines (obviously extremely simplified):
* microorganism infects host
* microorganism takes energy (in var. forms) from host to reproduce
* host is none to happy about thieving microorganism & tries to get rid of them
* microorganism is happy, if expulsion gets them to a new host (therefore might actually get annoying enough, just to actively trigger expulsion, even if host's immune system would not care otherwise)
Correct so far? If so, why are there no diseases which are actually beneficial to the host - either at least beneficial enough, to offset the energy-cost, or, ideally, so beneficial, that the host will WANT to spread it to family and friends - or actively seek to get infected in the first place? E.g.: a microorganism that increases pheromone-production & thereby makes its host more attractive, would probably spread rather well.
The only cases I can think of that are at least somewhat like that are Sickle Cell Anemia, and, come to think of it, I wonder whether the species making up our gut flora do not fulfill these criteria as well (though probably not - no spreading to other hosts, apart from childbirth, so not really infectious?)...
EDIT: Yes, obviously "disease" would be the wrong term in this case, sorry for that. Make it "beneficial infections" instead, and the question still stands.
| The very nature of the word disease does not allow for any kind of benefit. Anytime an organism interacts with the human body in a positive way, it is called mutualism. However, it is hypothesized that early in evolutionary history, small, bacterium-like prokaryotes developed a mutualistic relationship with eukaryotic cells and gave rise to the mitochondria, with their unique mitochondrial DNA.
Further, there are bacteria in our intestines that also provide us with many benefits, such as breaking down things we have not digested and providing us with vitamins. Said bacteria also compete with harmful bacteria and fungus, thereby helping us to avoid infections. A woman once took antibiotics for a year and developed a yeast infection all the way into her colon because her native bacteria were being killed off, allowing the yeast to fill the empty niche. Technically we all have an "infection" of these helpful bacteria, but we don't call it a disease because its not a "dis-ease;" its a good thing.
Sickle cell anemia is not an infection. It is caused by a genetic mutation, where a glutamic acid is replaced by a valine in the protein chains of hemoglobin. It does assist in defense against malaria, but is not itself an infectious disease that is helpful. In fact, if you are homozygous for sickle cell, you will probably suffer a great deal before you die an early and painful death.
EDIT: It is also hypothesized that retroviruses (viruses that can insert their genome into ours) have made many beneficial contributions to our genome over the course of our long evolutionary history. | 46 | 49 |
ELI5:What is "the Great Man" theory? | I heard of it when topic was history but never understood why? | There's a lot of different ways to interpret history. They're all valid to different degrees and achieve different things, depending on what you want from history.
The Great Man theory of history is built around memorizing famous world leaders and people who drove movements. They would argue that Hitler is responsible for the Nazi state, and that Churchill played a tremendous role in defeating him. This style of history is very inspiring - people like to have heroes and villains, and they like to imagine themselves becoming heroes one day. Proponents argue that it helps to bring the lessons of history into sharp focus, making it easier to learn from them. It's also much more testable, since declarations or statements become the driving force of history.
Other theories of history would say that Germany wanted a Hitler at that time because of prevailing social and political values that were driven by complex social, economic, and cultural factors, and that Hitler was just in the right place at the right time. They say that someone else, maybe Goering or Rommel would have taken Hitler's role if he hadn't. Similarly, they'd say that Churchill became the leader of Britain because Britons wanted it that way, and that the national culture of defiance and standing for the establishment and world order lead to Britain's role in WW2, and the selection of a man who voiced those thoughts well. This interpretation of history is much more plausible, but less inspiring, and makes us feel like we can't really learn lessons from history or change the world. It adds a sense of inevitability to history, but ultimately that may be the correct view of things.
So, to look at it today: Is Donald Trump responsible for the rise of the far-right Tea Party movement in America and it's sudden conquest of the Republican Party? Or is he merely the symptom of that cultural movement, someone who happened to be saying what people wanted to hear? History is more memorable, more inspiring, and feels more under human control in the case of the former, but the latter does seem a bit more plausible, if hopeless. | 60 | 30 |
ELI5. How do websites like ‘Ancestry’ and ‘23 & me’ work? | I am not sure if it is the altered state I am in, but I can’t seem to understand how these websites are able to track back so far before DNA could be analyzed and understood or even known?! | They compare your DNA to the DNA of modern people in other regions. Their equipment is meant to search for certain common markers with other groups. So let’s say they take your DNA and run it through their database. They find that your DNA is most similar to people who live in southern Italy and you also have some similarities with Hungarians. Your results come back mostly Italian and partially Hungarian. | 15 | 16 |
ELI5: Why is it when I scratch one part of my body sometimes I can feel it somewhere else? | I had shingles awhile ago and now I have a scar on my stomach and often times when I scratch the scar I can feel it on my back. Why is this? | The skin on large areas of the body, such as the back and stomach, are split up into regions called dermatomes. Each of these dermatomes are supplied by different nerves. When a nerve supplying a dermatome is stimulated, it sends the signal back to spinal cord and the brain to process it. However, upon leaving and entering the spinal cord these nerves are bundled into plexuses (which are like circuits) which allow them to split, combine, and recombine with nerves going to different areas within that same dermatome. Because of this "tangling" of nerves, when 1 nerve of that bundle is stimulated, it can cause other nerves in association with that nerve to fire a signal. The brain doesn't process it separately, it just lets you know that region a has been stimulated regardless if it was something external (touch) causing the stimulation or if it was piggy-backing on the signal from another nerve in that region.
When the virus that produces shingles becomes active, it attacks the nerve roots of one of these dermatomes which is why the rash is only seen in one strip of the body versus everywhere. The body has a rough time healing nerves (really complicated process) which is probably why you would experience this more in this region after healing.
Source: Second year medical student | 14 | 53 |
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