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Nov 3, 2021
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I think you can just check and intelligence is being positively selected for over evolutionary time scales. See eg https://www.nature.com/articles/s41598-018-30387-9 (random study, haven't done a deep dive but I believe it's representative).

This doesn't mean things haven't reversed in the past few centuries, but that probably hasn't had too much of an effect yet.

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Maybe I'm misreading your argument, but neanderthals and other archaic humans almost certainly selected for intellect as well. Neanderthals had rudimentary art, decoration, funerary practices, almost certainly language, etc. which are all things they developed extremely quickly on an evolutionary time scale compared to their ancestors.

It seems likely to me that the conditions for massively accelerating intelligence are an environment and a species toolkit that makes each marginal improvement in intelligence create outsized gains in reproductive probability. The climate and environment of the archaic past was much more hostile than the one we have today, and with even very basic technical advancements (the use of specialized stones rather than general hand axes, for example) the odds of survival shoot up in that environment.

The human species is no longer facing those conditions, so selection for intelligence has slowed down. Our growing biomass is just the outworking of a process that has more or less been pre-determined since we discovered writing and gained the ability to greatly increase information transmission.

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You need to think in terms of ecological niches. Organisms (plants and animals) evolve to fill each available ecological niche in a given environment/ecosystem. For some of those niches, like say pack hunting ruminants for protein and fat, intelligence will be an asset. For others, like turning sunlight into plant food, it won't be. This is what determines if it gets selected for.

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Nov 3, 2021
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I agree, it does seem odd that there would be more selection for intelligence among hunter gatherers than in the past few hundred years, when the economic and social returns available to people of above average intelligence seem so obvious. Human social dynamics are complex, though, so it could be any number of factors.

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Nov 4, 2021
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I feel like selection in general is weaker than it used to be, because almost everyone survives to adulthood, and most people have kids. Maybe the sweet spot for low selection was in the decades after 1945; few young deaths, and also few childless weirdos like me.

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Come. Are you seriously debating whether horses are smarter than houseflies? The fact that it's hard to judge close calls does not in the least call into question the capability to judge *at all*.

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Nov 3, 2021
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We can easily observe intelligence in animals, because we define it as "solving problems." They don't have to be problems that are interesting to humans, and indeed they are typically not, they are problems interesting to the animals, like finding food or how to get out of or into some space with barriers, et cetera.

Anyone who has owned animals knows that some are clearly smarter than others. Some dogs are smart, some are dumb, and any dog-owner can tell that. Some dogs figure out how to beg or steal food cleverly, some are dumb about it, some never figure it out. You can fool some dogs easily, some are much much harder to trick.

Some horses are smarter than others, e.g. can figure out how a latch works, or when a gate is likely to be left open, and someone who works with horses can see that easily enough. Heck, I've seen someone who kept rats as a pet observe that some rats were clearly smarter than others because they could solve problems interesting to rats -- finding food, shelter, mates, whatever.

It feels to me like you're getting lost in mechanistic details, and overlooking the basic crude observational data, which is that we can clearly see that individual members of a species can solve problems important *to that species* at differentiated rates of success, over time. We can also observe that one species can solve problems interesting to that species, on average, better than another, so we can readily conclude one species is smarter than another.

I'm sure it's much harder to distinguish fine gradiations of intelligence of dogs than it is of humans, because we know much less about what's important to a dog, and how dogs think. But that is, if you will, merely implementation difficulties, a challenge to experimental or apparatus design, it doesn't call into question the entire existence of the trait.

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Yeah I think you are still favoring the types of problems that people think are impressive. Insects are great at surviving and solving problems in ways that humans are totally uninterested in or actively hate.

Virtually every species that humans consider to be particularly intelligent is one much like us, i.e. a social-group living species that hunts or is at least omnivorous. Dogs, dolphins, whales, elephants, primates, wolves, etc. So either living in a socially cooperative manner confers greater intelligence (which would make sense, because having to consider not just your own interests but also how the group will react to your behavior is a lot of cognitive load), or we just tend to be particularly impressed with forms of intelligence that we can recognize and that serve our interests.

I take your point in that I've had pets that were clearly smarter or dumber than others. But it's also hard to say in some cases. People tend to consider dogs smart when the dog is easily trainable and likely to do what the human wants. I'd say cats are smarter than dogs but people tend to think dogs are smarter because they're submissive to humans and want to please them. One of my dogs learns new tricks at literally about 200 times the speed of the other -- it's a stark difference -- and is much more attuned to people and how to manipulate them. But the stubborn/"dumb" one has far superior survival skills with respect to being appropriately suspicious of danger, knowing when to hide or approach, hunting skills, etc. If they weren't living with and dependent on humans, I would expect the "dumb" one to have far greater survival chances and the smart one to be dead within a month.

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Well, there are two possibilities here:

(1) Intelligence confers a survival advantage to humans, and natural selection has tended toward optimizing it.

(2) Intelligence does not confer a survival advantage to humans, and the fact that humans -- every one of them -- are about umpty times smarter than dogs or rabbits is just a weird coincidence.

The problem with (2) is that it asks us to believe that *the* most salient characteristic of a species is mere accident. It's like observing that cheetahs are really, really fast in a sprint, but this is just an accident, and their survival as a species actually derives entirely from the clever design of their spots.

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In terms of very recent evolution, there's reason to think western europe was eugenic between 14th-20th centuries because so many violent criminals were being executed and the upper classes were having relatively more kids than the lower classes. Not an exact measure of changes in intelligence but its something.

https://journals.sagepub.com/doi/full/10.1177/147470491501300114

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This essay is very interesting, and it led me down a fascinating rabbit hole.

However, it honestly seems like his claims about the genetic effects of capital punishment are wildly overstated, by a factor of ten.

I was very shocked by his claim that men in Late Medieval/Early Modern Europe had a 0.5-1% lifetime chance of being executed, due to an annual execution rate of 1 execution per 10,000 people. When I looked up the source he cites for this claim (L'Occident est Nu, by Philip Taccoen) on Google Books, I discovered that he really does appear to have simply misquoted Taccoen: the latter says that Early Modern England and Malines, as well as 18th-c. France, executed one out of every *hundred* thousand people annually.

(The other source this paper cites for the execution rates claim, Paul Savey-Casart, isn't an independent source but simply the one cited by Tacoen as the source of this claim. Based on the lack of a page number given for the Savey-Casart citation, I strongly doubt that the authors of the paper tracked down Savey-Casart's book themselves.)

It's entirely possible that I'm totally wrong and there's some obvious issue I'm missing--but it really does seem like they founded a significant part of their thesis on a claim that could have been disproven by simply double-checking what their source actually said.

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I guess I’m confused why generalizability to other species has any relevance on g as it applies to humans? It seems fairly obvious that intelligence has been strongly selected for (how else could we get so smart).

A point that it seems you’re trying to make is that humans aren’t any more intelligent than other species, we all fill our niches equally well. A bee could look at a human with a PhD and think them unintelligent because they don’t know how to build a beehive. The part that I think this view misses is that bees (and all other non-human animals) only know how to do one thing. Each species of bee is evolved to build one type of hive and produce one type of honey and collect nectar from one ecosystem’s flowers. Humans on the other hand have been able to spread over the globe over the last ~40,000 years into every possible ecosystem and have adapted - quickly and with our intelligence, not with slowly natural selection - and it is that capability that we use to justify our intelligence relative to other species.

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Nov 4, 2021
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I don’t think anyone makes the claim that intellect is always a positive trait, as people have mentioned elsewhere in this thread it involves a heavy trade off in between general-purpose intelligence and energy usage, so in most niches it is not something that is especially selected for.

Rather, I think that intelligence is something that became useful in human’s particular niche (perhaps due to our ability to learn socially) and then rapidly evolved to fill that niche

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Nov 4, 2021
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I'm not sure what you mean by the second part, there is no purpose of intelligence, its that more intelligent people outsurvived and outreproduced less intelligent people, causing the average intelligence of the population to rise. What is left to explain?

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I think your word choice is misleading, here, since you're trying to distinguish the "merely bright" from "geniuses"; describing the former as "low intelligence" is true in the relative sense, but the people you're thinking of are still above average intelligence for the general population

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An extremely hard working person who is obsessed with their subject but has an IQ of 105 can probably earn a PhD in most fields.

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I doubt that. In my experience, smart people overestimate how smart the average person is. (because smart people generally live and work with smarter than average people). Also, I know a few people who failed the qualifying exams in my PhD program in a natural science. They were all, every one of them, hard workers who loved the subject. They were also all much much smarter than 105 IQ. They just weren’t smart enough for the program.

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I wouldn't include hard sciences in my statement. There are a lot of easier fields.

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see here: https://www.iqcomparisonsite.com/occupations.aspx

Among college professors, 10th percentile = 97, 25th percentile = 104, 50th percentile = 115.

I'd expect college professors to be a bit higher than PhDs in the same field because there's an additional filter in the job application process. The average IQ of PhDs has probably declined over time as the number minted per year has increased ~20x since the 50s. I've heard elsewhere that the average IQ of PhDs was 125. That might be a much earlier sample. Or it might be the case that the easiest fields (such as grievance studies) have higher rates of PhDs becoming professors to spread the mind-virus instead of going into industry to do something useful, since there's nothing useful to do with bullshit fields. That could make the average of professors lower than the average of PhDs even if each field has above-average professors relative to the PhDs in the same field. (assuming almost all professors have PhDs)

Anyway, that was a long digression, but if the 25th percentile of college professors have an IQ of 104, it's totally plausible that people with very high noncognitive traits but IQ 105 could get PhDs in most fields.

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Point taken, and I’d agree with you if “most fields” can be taken to exclude STEM.

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Please clarify what you mean by less agreeable(grumpy?) and why you think that it would correlate with intelligence.

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Less agreeable does not mean grumpy, it means literally less likely to agree with others, i.e. go along to get along, concede on matters, etc. One can be quite cheerfully disagreeable. Higher intelligence means more likely to think that one is right about things, come to one's own conclusions, and less likely to go along with what others say just because they say it.

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I asked what he meant by agreeable because, what you are describing above is not the dictionary definition of agreeable as I understand it. It is generally used either "as agreeable to x" or just "agreeable" where means pleasant. I think the latter is along the lines of he is agreeable to be around(where the agreeable one is the thing being agreed to).

I strongly disagree that higher intelligence equates to "more likely to think one is right about things." Haven't we had at least 1 post describing the opposite? Less-smart people think they are correct. More-smart people understand that things are complicated and they are better able to appreciate that they may not be. Everyone comes to their own conclusions.

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My understanding is that the Big Five Personality definition of the agreeableness trait pretty closely aligns with "goes along to get along."

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I think you are mixing up tendency to update one's priors and adjust to new facts (which would be correlated to intelligence) and what I was talking about in respect of "being right", which meant that one is not going to say that something is correct, when it obviously is not, just because of social pressure. I was talking about thinking one is right as a matter of sociability rather than being open to changing ones mind based on new information.

Example: you are sitting in a room with ten people and everyone is asked to come up with an answer to some question where there is an obviously correct versus incorrect answer on something factual (maybe a math problem). If the other nine people absolutely insist that the wrong answer is correct, and want you to go along with them, and you insist that your correct answer is right, you are probably not very agreeable.

Agreeable is referenced here in relation to the "Big Five" personality traits, which is what is shown in the table above, and it does indeed show that the cognitive genes are inversely related to agreeableness (i.e. more genes for cognition/IQ make you less likely to be agreeable). But the non-cog genes were positively correlated with agreeableness. The literature I've seen shows there is no strong association either way with IQ. Which is probably because the trait of "agreeableness" has a bunch of sub-traits which probably work at cross-purposes. "Compliance with social norms" is one. But so is empathy and compassion. And also sociability. Honestly, these are all pretty different things and perhaps should not be lumped together at all.

In any event, agreeableness should NOT be considered "grumpy", which would go more towards the neuroticism factor of the Big Five personality traits (i.e. moodiness and emotional instability).

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I was not aware of "agreeableness" or the "Big Five." That was why I had asked for clarification. On the "being right" issue, I suspect I just misunderstood you. I read being right as "being certain" and in my experience, one of the hallmarks of very bright people is the opposite.

There is a tendency to hedge: "if feels like", "is it possible that", "this reminds me of." This is perhaps increased awareness of ones innate(non-numerical) bayesian thing. Interestingly, this can also comes across as agreeableness(hedging) but at least some of it is a deeper awareness of the complexity of issues and an ability to acquire understanding without confidence in a solution.

Undoubtedly, High IQ people feel less need to prove themselves and are well aware of potential benefits of being agreeable, as well.

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Yeah, sorry, I wasn't very specific. Though you caused me to go look more at what constitutes "agreeableness" in reference to the Big Five personality traits, and it turns out that there is quite a bit of disagreement on this and it has many sub-components that don't seem very related. Empathy versus being submissive/easily conceding to the group versus stubbornness versus friendliness -- it's not clear to me whether these traits really have anything to do with each other whatsoever. So perhaps it isn't surprising that IQ doesn't show any strong correlation to agreeableness one way or the other. And it's fairly context-dependent anyway. I'm pretty far towards being extremely laid-back and easy-going in 90% of situations, EXCEPT in instances where I'm expected to agree with something I think is factually wrong, in which case I'm horribly obstinate and entirely disagreeable. That's probably not that unusual, and while I think that would measure as low neuroticism low agreeableness, I'm not sure.

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This has, naturally, been studied, and IQ has been found to have a modest positive correlation with agreeableness.

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I don't think this is true, most research I've seen shows no relationship of agreeableness with g. The chart from this study above also shows an inverse correlation with cognitive genes (but a positive correlation with non-cog genes).

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> Depression is just bad. I strongly recommend not having it. Don’t even have any risk genes, if you can avoid it. All of you people trying to come up with clever evolutionary benefits for depression, I still think you’re wrong, and so does the genetic correlation with cognitive and non-cognitive aspects of educational attainment.

I am not a doctor or biologist, but the fact that rates of depression are heavily correlated with ethnic background (at least that's the stereotype; I haven't validated this), I would expect that depression is genetic in nature. And if it is genetic, I would assume that there is some kind of compensatory benefit to keep it around.

I don't know what the benefit is, and it seems pretty all-around shitty to me. But why would evolution specifically give you depression genes? There has to be some evolutionary benefit

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Nov 4, 2021
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Those who don't want to be a burden on those around them could just leave, so they are no longer around them.

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Is it actually that correlated with ethnicity? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1199525/ (first study I Googled, I'm not claiming to have looked into this deeply) says it's 8% of whites, 9% of blacks, and 11% of Hispanics. That seems pretty similar - any differences could be accounted for by social deprivation or culture.

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Aren't suicide attempts, or even just suicides, not a better measure for this sort of comparison?

In my own searching (which admittedly was in a journalistic context rather than an academic one) I seem to remember finding that depression rates seem to suffer from a large number of effects that skew the rates of diagnoses, chief among them the fact that merely being the sort of person who deals with those sort of problems by going to get diagnosed instead of simply stewing in them makes someone a non-typical example. Suicide rates bypass this for the same reason murder rates are great for looking at crime: it's tough to ignore when a person is gone.

I don't know to what extent the study you linked can control for that, but looking at suicide data presents a very different picture, with there basically being a hard split between Whites and Amerindians on the one hand, and Blacks and Latinos on the other. The former group has suicide rates about double the latter. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8155821/

This doesn't necessarily show the effect to be genetic, but it certainly leaves it open as a possibility.

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Cultural confounders seem to be a pretty big issue here. I'm thinking specifically of Asian acceptance of suicide compared to Western disavowal of it. Breaking that down further, it looks like religion is a significant component of it. Black and Latino populations are known to be more religious (of the type that is anti-suicide) than White and especially Asian.

I don't know that this is necessarily true, but that's been my understanding.

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That's a reasonable point to make, though I struggle to think of what exactly the cultural co-founders could be, given:

- Asians have the lowest rates of religiosity, but also very low suicide rates, while Blacks have the highest rates of religiosity, and yet also low suicide rates

- The two races with the largest percent of single-parent households are Black and Amerindian, and yet these two lie on opposite ends of suicide rates

- The two races with the highest rate of gun access are White and Black, yet they lie on opposite ends of the spectrum as well.

- The two wealthiest races per capita are Asian and White, yet they are opposite in suicide rates. The two poorest are Amerindian and Black, which are once again polar opposites when it comes to suicide.

There might be some sort of cultural component, though I'm unsure what research has been done on that, but it isn't clearly evident from any factor that I would expect to influence suicidality

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I doubt it's the explanation, but I've read that Black children are actually more likely to have both parents than White children. We assume the opposite because Black children are less likely to have married parents, but Blacks often stay together without marrying. (As it happens, I read this the same year that I did taxes, and two of my clients were an unmarried Black couple with a child.)

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An interesting perspective that I'd never considered. If this is true, it would make for a fantastic example (for myself at least) of how sometimes basic statistics can mislead you from the reality on the ground.

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I'm not sure what you mean by kids being "more likely to have both parents" -- all kids have two parents, unless one or both are dead. But if you meant LIVING with both parents, though unmarried, this is not true. Black children who live with both parents, including both married and unmarried but cohabiting, is still less than 45%. For white kids that's 80% and for Asians, almost 90%. There's a huge racial discrepancy and MOST black children do not live with two parents, while most children of other races do. The portion of unmarried parents who live with their kids is about the same for all races (6-9%) except Asians, where it's unusual.

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strength of social networks come into mind. a more 'tight-knit' black family may provide pressures to prevent people from suicide if you have a functional-ih family structure.

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Some economist should find a natural experiment and study whether or not converting to X religion or being adopted by X culture actually has a protective effect against suicide (or increases income, or increases life expectancy, or increases life satisfaction, or whatever).

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Could Japan being counted as part of Asia be confounding the Asian numbers? They have a history and tradition of ritual suicide for various reasons as part of their culture (less often in modern times but still a thing). My intuition is that people with fewer existential problems (hunger, thirst, shelter, power etc) tend to be less able to cope with the smaller problems that remain, which means I would expect whites to be "winning" in suicide rates while everyone else is lower but still around the same order of magnitude.

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The rituals and traditions for suicide in Japan were related to behave in war though. The banzai charge/gyokusai attacks.

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There are likely different confounders there - people are more likely to commit suicide when they have the easy means to do so, which probably varies a lot by culture, region, wealth, etc.

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No because suicide isn't a good proxy for depression. It has lots of non-depression causes (eg alcoholism, schizophrenia, impulsive action after one really bad day) and lots of non-depression preventors (eg religious people are much less likely to commit suicide, maybe because of fear of afterlife)

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While I understand that those make for issues with using suicide as a proxy in general, are they truly an issue for this particular case (racial comparison)?

Schizophrenia has decent evidence of being race-neutral, rates of alcoholism aren't so starkly different between races to account for anywhere near the gap (except perhaps among Amerindians? I am failing to find any decently reliable dateset that includes them in alcoholism data,) and unless white people are comparatively incredibly impulsive, impulse control wouldn't be a differentiating factor.

And as far as preventors, see my response to Mr. Doolittle above. Races with similar rates of religiosity fall on opposite sides of the suicide spectrum. The same goes for income, educational attainment, gun access, absentee parents, etc.

As far as I can tell, considering these factors only make the racial separation even more stark.

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Not all religions are the same, and definitely not interchangeable. Western religions (Jewish, Christian, and also Muslim) have a very negative view of suicide, which I don't think exists for Eastern religions. Japan is well known to have very different views of suicide than in much of the rest of the world.

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Just ask Hamlet about suicide...

To die, to sleep;

To sleep, perchance to dream—ay, there's the rub:

For in that sleep of death what dreams may come,

When we have shuffled off this mortal coil,

Must give us pause.

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I bet depression and suicides are correlated with more free time (being less busy), more of the basic human needs covered (food, shelter, sex, security) and less close relationships. And it's not only depression but even health in general and life expectancy.

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Didn't Emile Durkeim mention how protestant regions of Europe had a higher rate of suicide than Catholic areas as well as how industrial or urban the area was?

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Well, I'm only a layman, but here is a possible benefit:

Don't mildly depressed people have a slightly more realistic view of reality compared to the rest of us?

So let's say you are in a historical environment and you believe something maladaptive that you derive negative utility from but is not so bad that you aren't dead.

This over time depresses your mood, enables you to see reality better and gives you a chance to change your mind.

Depression acting as a belief/behaviour switching function.

Historically the lack of motivation wouldn't have been to much of an issue as you are cold, hungry or horny enough to push past it. The lethargy may even be good in giving you slightly less caloric upkeep while you figure out what you are doing wrong.

Of course, if depression gets too deep, that's a failure case. But hey, we know evolution only aims for "barely good enough".

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Depression is the failure case. Being sad because things are going wrong is just normal behaviour.

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So its only labelled depression when the results are bad? In that case by definition depression is always bad as Scott said. I always imagined it as a spectrum sort of thing rather than an on/off switch.

Your right I should have used the term sadness rather than depression if depression is the technical term for the failure case.

I kinda see them as the same thing though differing by degree?

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That something must be bad to be considered a psychiatric disorder, I believe is true of all of the psychiatric disorders. Pretty much always 1 of the DSM requirements is that it interferes with your quality of life.

From nih.gov for "Major Depressive Episode":

- Symptoms must cause significant distress or impairment

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I think this labeling issue is at the heart of the problem Scott's trying to get at. If you only label bad cases, then all cases are bad. If you label adaptive cases that don't reach the level of bad (we call it "sadness") in the same category, we might be able to say something meaningful beyond "depression is always bad."

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As someone with lots of experience with depression, for me it's not about having a realistic view of reality; it's not caring about reality at all. When I'm having an episode, it's impossible to imagine anything being interesting. It's all just boring.

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>Don't mildly depressed people have a slightly more realistic view of reality compared to the rest of us?

I think perhaps you mean pessimistic people, not people with clinical depression.

That being said, experts who are optimists tend to make significantly more accurate (20% more) political predictions than pessimists (Expert Political Judgment : How good is it, Philip E. Tetlock 2005).

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Somebody did a study with a box with lights and buttons, and asked people to estimate how much their button presses influenced the lights. Most people overestimated, but depressed people tended to get it right.

I think maybe I read about this study not replicating? But I've read about so many things not replicating I might have gotten mixed up.

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Key question here though: by depressed people do you mean people at that moment suffering from depression or just people at some point diagnosed with it? Because my experience of suffering from depression is that your ability to analyse and observe is markedly different depending on whether you are suffering an episode or not.

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Pain is just bad. I recommend not having it. Yet its absence is maladaptive.

Abraham Lincoln seems to have had depression. I suspect that high IQ + depression (to a degree that isn't disabling) might be more suited to navigating times of strife than high IQ + alternative, particularly for leaders/decision makers.

What's the alternative mental state during lengthy, difficult circumstances? Cold indifference? Cheerfulness? Better to err being in a depressed state than one of emotional deadness or irrational glee.

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Sadness under circumstances where it makes sense to be sad is not depression. Depression is constant, hopeless sadness for no reason.

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No there doesn't. Natural selection works on the entire genome at once, it doesn't individually optimize each and every gene. (If nothing else, the space is so highly dimensional it would need a huge amount of time to do that.) It's completely possible for natural selection to optimize foo (which confers a major survival benefit) which alas brings along bar (which confers a mild disability) for the ride, because the two genes happen to be hooked up in the DNA world in any of the various ways that can happen.

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There seems to be an obvious benefit to seasonal depression at least. In winter:

* there's little food to eat

* it's cold outside

* meeting strangers will get you ill easily

* there's no work to be done on the fields

Therefore if you're naturaly inclined to

* eat little

* stay inside and not meet anybody

* sleep all day

…you more likely to survive winter. Especially if you live in the middle ages or earlier.

Note that none of these conditions will get you a smart brain or a high function level, but that's not the point of survival.

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You do realise that agricultural societies work throughout winter? It was the only time that was available for non-routine work, although there were annual activities as well. Winter crops, preparation for early spring planting, finding fuel, making repairs, clearing drainage, pickling and brewing, digging out the sheep, taking in new land... Not doing these things (often communal activities) screws up your chances of prospering and therefore surviving/having your children survive.

Also, the positive genetic argument for depression has to deal with the minor issue that it generally removed your sex drive, which is an evolutionary fail.

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Are human beings, biologically speaking, more a product agricultural society or of pre-agricultural society? I would presume the latter, and so to the extent that depression is biological I could see how it could make sense evolutionarily.

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Keep in mind, not all evolutionary benefits remain beneficial in such a different context as the modern world. An obvious example is food, we have access to more calories than we know what to do with and adaptations to save calories wouldn't be advantageous today.

It could be that depression used to have an evolutionary benefit but somewhere between hunter-gatherer and flappy bird it lost that advantage and just became purely negative.

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Title on the graph seems wrong, "EA FDR correction tries to impute the results from the main timeline, where Roosevelt was an effective altruist and diverted the resources of the Depression-era US into curing all diseases."

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It's a joke about the key for the grey line.

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But I also initally thought Scott had made a mistake! (some of us read the text underneath to figure out what on earth we're looking at before reading all the acryomns in the very dense picture!)

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It’s also a play on the bad leading in their figure legend — EA and lines below it (incl. FDR) are separate labels.

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"As of last time I checked, the leading hypothesis was that schizophrenia genes were just really bad, evolutionary detritus that we hadn’t quite managed to weed out."

Is it really? I thought the idea that schizophrenia genes/low levels of schizotypy were somewhat positively associated with creativity (when they don't result into full-blown schizophrenia, which does decrease creativity) was rather widespread. I wouldn't necessarily have expected creativity to correlate with educational attainment, but it's clearly a positive trait that is easy to think would be selected for in many environments - not quite what you'd expect from "evolutionary detritus". Eg https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1601-5223.1970.tb02343.x or https://www.nature.com/articles/nn.4040 but a Google Scholar search would return much more

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As I posted in my comment, Robert Sapolsky discusses this idea at length here: https://youtu.be/4WwAQqWUkpI

Awesome for the overview and you can listen while doing something else, too.

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I have heard the same thing. I don't have any cool links to share on the subject, though. :(

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I'm not familiar with this type of research at all. When one says "found genes for intelligence" or "found genes for educational attainment", what does that mean? Is the claim that some portion or portions of the human genome have been identified that, when they look like 'x', 'y', or 'z', make a person unintelligent, of average intelligence, or very intelligent, respectively?

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Suppose you have 100,000 genetic tests and you know the educational attainment of each individual. If a sufficiently large number randomly selected sample should have approximately the same average educational attainment. If instead of selecting randomly, you select by presence of a specific gene, and if educational attainment varies between the two groups, you have a correlation. Repeat for next gene.... (Where a gene is a DNA sequence that is, in its entirety, passed on by inheritance)

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Google tells me that humans have between 20-25k genes. That seems like a lot of free parameters, especially when you start to consider combinations of different genes. I'm not trying to dismiss a field I know nothing about out of hand, but I worry about chance correlations with a parameter space that large. What's known about function of these genes? Is there any reason to suspect they would influence cognition? Do different studies using different test populations tend to find correlations between intelligence (or whatever trait you are interested in) and roughly the same set of genes?

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Only 11 or 22 intelligence-related genes seems *really* low out of a pool of 20-25k.

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A typical study might be looking at 2.5 million SNPs. So if they didn't know statistics and just checked for p<.05, we'd expect them to get on the order of 100k false positives.

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"but I worry about chance correlations with a parameter space that large."

It was a huge problem when using small (a few hundreds) sample sizes and a small set of candidate genes, leading to many many false positive "discovery" during the nineties and the aughts. But now the studies use sample sizes of several hundreds thousands people, leading to much higher reliability, and yes, the snp (=position within the genome)/traits associations are replicable, e.g.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6003860/.

("First, GWAS findings are highly replicable. This is an unprecedented phenomenon in complex trait genetics, and indeed in many areas of science, which in past decades had been plagued by false positives. ")

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Nice summary of the current state of research here in the link below. I really appreciate the fact that they listed the major controversies about genes and intelligence without commenting on them — but just giving links to footnotes. The fact that they admit there's controversy is big step forward if you ask me. Lol! They also have a section on Parieto-Frontal Integration Theory (P-FIT), which seems to be 21st-Century phrenology with brain scans. I guess I shouldn't be snarky P-FIT, but when one studies the history of science one sees recurrent meta-theories arise over and over again.

https://www.nature.com/articles/s41380-021-01027-y#:~:text=A%20positive%20genetic%20correlation%20indicates,likelihood%20of%20developing%20the%20disorder.

This next paper claims to have identified 187 loci that have a role for neurogenesis and myelination that seem to affect intelligence. Pretty dense (or maybe my myelination quotient isn't high enough to immediately grasp it).

https://www.nature.com/articles/s41380-017-0001-5

This third paper finds that there are 22 genes that seem to affect IQ. Can't figure out how to line up their findings with loci described above.

https://www.nature.com/articles/ng.3869.epdf

There was another paper I read a few months back that insisted that there were only 11 genes that are strongly correlated with IQ. But now I can't find it. I would have been interested to see if any of the 11 overlap with the 22 paper.

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"Both cognitive and non-cognitive skills are correlated with neuroticism, which I guess makes sense - that’s probably what makes you do your homework on time."

They're both negatively correlated, though, right? So this also means that NonCog has correlation in the "good" direction for each of the Big Five, which makes sense.

Also, I'm trying to think of how to recreate this analysis, but without looking at genes. I guess it would mean that for a given educational attainment (say, college grads), people in the bottom 10% of IQ are more likely to be schizophrenic than the average college grad? Or at least have more relatives with schizophrenia?

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You're right, thank you, fixed.

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The negative correlation with neuroticism makes sense to me in that on the Big Five, neuroticism means more like "emotional reactivity" than like "obsessive."

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I'd like to see some exploration of the ADHD–IQ link. To me it seems plausible that ADHD genes might affect intelligence test scores without actually affecting underlying intelligence. This could be investigated by looking at the results of the subtests: if ADHD genes have an equal effect on subtests that require attention (such as digit span) as on subtests that do not (such as vocabulary), that would be evidence against my hypothesis.

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I think that sort of perspective on intelligence highlights the fundamental problems of this research - the bedrock for “smart” are subjective.

For example, there’s a very famous story about a world class ballerina (use Google for the specifics) who was terrible in school as a child, so her mother took her to see a psychologist. He watched her and asked the mother what she enjoyed most and what she did in her free time. The mother said she likes to dance so the psychologists simply said then that’s what she finds most interesting - if she can’t pay attention to arithmetic, she’ll probably pay attention to dance routines. And she went on to fall in love with dance and become a world class dancer.

In today’s world, she probably would have been given ADHD medication and sent on her way. She might have thought she was dumb all her life, but it’s impossible to deny that she was a genius in a kinesthetic sense. Her underlying “ADHD” was not a cognitive benefit in the classroom, but was in the ballroom. This genetic analysis does not assess that sort of professional assessment in correlation with IQ.

I also seem to recall that Scott has a pet theory that a lot of ED docs have ADHD and thinks that might benefit them in their environment. But I wonder how their genes would fall on this type of table? Are they simply outliers who take medication or somehow overcame their ADHD to achieve a high level of academic and professional success anyway?

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Nov 3, 2021
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My question is why shouldn’t kinesthetic ability or other things like artistic genius or language acquisition ability be included in “intelligence”. It’s somewhat of a subjective umbrella to begin with. That’s my point.

The point is made below that ADHD might manifest as a latent desire for some specific things like music, dance, math, etc. and so that may imbue a certain drive for talent in that domain but also make for sizable distraction from others.

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I'd say the reason digit span and vocabulary are both included in IQ tests is that there is evidence that they are affected by a common factor, which we tend to refer to as intelligence. I am not aware of any evidence that ability to dance has any strong link to that same common factor, and, might I add, having seen a fair number of intelligent people dance, I have not noticed such a correlation.

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"having seen a fair number of intelligent people dance, I have not noticed such a correlation." nicely said!

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i think this read is loosely related, about the seven arts, aka skills to study and education oneself on https://www.delanceyplace.com/view-archives.php?4504

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In my experience ADHD mostly hurts your ability to concentrate on subjects or tasks you don’t find intrinsically interesting or when there is a competing topic to think about that is more interesting than your current task. This is why many people with ADHD end up with grades that differ wildly between academic subjects. If someone with ADHD finds every or almost every relevant subject in undergrad and medical school fascinating and doesn’t have a lot of competing interests, they can do very well.

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Meant to reply to Hippo’s comment. Sorry about that.

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Yeah that’s a good point!

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Anecdotes are not data, but.....

I can attest to this. I was recently diagnosed with ADHD, but haven't taken medication so far. However, I was one of the more obvious cases since childhood.

I fully recognize myself as a completely different caliber of human when I am in focus/attentive vs when I am not. I also frequently take around 30 minutes to enter a focus state (the sensory deprivation of an exam hall helps, but the unfamiliarity of environment takes a few minutes to adjust)

It is incredibly irritating, because I would often be the person that helps friends prepare for examinations and help them understand hard concepts. But, when it came to the exam hall, I felt like my eyes & brain was dilated for the first 30 minutes. Then I'd slowly come back to the earth and rush through things as I started 'getting it', but never ended up reaching the end.

I feel like a cat sometimes. Giving off the appearance of a lazy organism with the intellect of a rock, until you actually need to be productive.

> hurts your ability to concentrate on subjects or tasks you don’t find intrinsically interesting or when there is a competing topic to think about that is more interesting than your current task.

Yep. I might as well use this as my elevator pitch,

> ADHD end up with grades that differ wildly between academic subjects

100%. I used to get Ds in classes that needed rote learning, including biology, but physics, math and english comprehension/essays came to me really easily.

> If someone with ADHD finds every or almost every relevant subject fascinating

Happened to me with Machine Learning. Went from a lazy bum to someone who was reading papers and textbooks for fun. Ofc, this was until hackernews and reddit pulled me back in. :|

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"In my experience ADHD mostly hurts your ability to concentrate on subjects or tasks you don’t find intrinsically interesting or when there is a competing topic to think about that is more interesting than your current task. "

Very interesting, thank you!

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The fact is there's very very few jobs you'll get by being a good dancer, and lots of jobs you'll get by being good at mathematical/logical reasoning. So it can perfectly well make sense to force kids to do the regular school routine -- if they can at least convincingly do it they might have a much better shot than if they try to become a dancer/footballer/whatever else.

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Right but economic conditions dictate what schools teach, so skill set demand changes. Dancing might not be prized today, but maybe 10,000 years ago it was for shamanic reasons or mating etc. (you get the idea). So on a genetic/evolutionary front people may have skillsets that are expressions of “genius” but in the current moment they don’t have the same economic value that we equate with “intelligence”. It’s just semantics and context.

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Even in today's society, I would predict a correlation between being good at dancing and reproductive success...

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When I was tested for ADHD they were specifically looking for this sort of subgroup divergence, so I believe that's a known thing.

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The problem is once you start seperating "intelligence" from "scores well in an IQ test" the whole analysis rather falls apart, since we don't have any other measure. Really this should be called "genes for IQ test score vs genes for educational attainment."

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I would define intelligence as g. Intelligence tests (and test items) differ in their g loadings, so It think it should be possible to associate genes with g instead of with test scores.

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Unless you have some empirical measurement of "intelligence" that isn't functionally equivalent to "scores well in a test of intelligence" then any effort to do the separation is going to be mere sterile philosophizing, at best.

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"ADHD and intelligence" is a horrible clusterfuck, because even by psychiatric standards the "thing ADHD describes" is a number of disparate things, and some of those things are even more explicitly social-determination than for most psychiatric terminology. ADHD can refer to hyperactivity, to idiopathic executive dysfunction, to very non-idiopathic executive dysfunction, to "boy", to "not middle-class". It's the wastebasket diagnosis to end wastebasket diagnosis.

Artificially low IQ results are a fairly common issue in the sufficiently neurodivergent population (their applicability to autism is notorious, see the writings of Donna Williams and Scott Aaronson on their own results; I suspect some of the negative correlation between IQ and schizospec neurotypes is due to a tendency to think in much curlier lines than those tests permit), but they're much more difficult to pattern over something as broad as ADHD. Some people with ADHD definitely have artifically low results as a consequence of their neurotypes, but these may be better seen through a different lens.

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I have a kid with ADHD-Inattentive and bipolar. His ultimate level of educational attainment probably will not be high, although he is pretty bright (good writer, bad at math, horrible at history). His docs have told me that many ADHD kids are delayed in terms of maturity, which sometimes affects decision making (not him, thank god) and sometimes affects initiative, self-discipline, and attention to deadlines (definitely him). So, he may in time manage college, but it won't be soon.

By the way, there is nothing good about having bipolar disorder. What's good is the medication that keeps my son out of the hospital or worse.

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Robert Sapolsky mentions in this lecture that a *little* bit of controllable oddness on the schizophrenia spectrum is useful for making usefully charismatic shamans, and that could explain its genetic advantage and persistence. The more extreme, uncontrollable end of the spectrum, on the other hand, isn't an advantage.

https://youtu.be/4WwAQqWUkpI

(Also, this is the one lecture from this series that Sapolsky has removed from his own YouTube channel. He says some highly cancelable shit in this one, which is a shame because it sure does seem to make sense to me.)

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+1 for Sapolsky

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I have often wondered if the various "mental illness" diagnosis that get made are only picking up on the people that are so far out of the norm that they register as a problem. Crochety old people, eccentric uncles, the "socially awkward" and so on probably have similar traits, but at more controllable levels. Millions of other people could have the benefits of the underlying cause, without stretching too far into a problem. We don't have the sophistication needed to identify someone who is *mildly* schizophrenic in a very positive way. We would probably label them as something else or not label them at all.

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“Weird”!

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I am pretty sure that some of things that are mostly harmless nowadays would end with me being dead if I lived say 300 years ago, and if "mental illness" diagnosis criteria would be applied then I would qualify.

(though - both me and my mother would be dead due to birth-related issues if I would be living 300 years ago)

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