[after_care]

> the opposite actually [1]

This is a much more controversial view than as suggested in the comment -- specifically there is very little data backing up the hypothesis that intelligence is decreasing. This is compounded by the fact that we really don't have great tools for measuring intelligence or a deep understanding of how it develops and manifests in humans. IMO the jury is still out on the general direction human intelligence is moving, but realistically if you are concerned the best thing you can do is improve environmental factors and educational access.

[stjohnswarts]

I would say just given the sheer number of people these days that we are more likely to get the tippy top of intelligence than say 3500 years ago. Just by the law of large numbers. Maybe I'm just less smart than the Minoans though and my devolving mind should shut up about such things :)

[dclowd9901]

There is 1) survival of the fittest and 2) random genetic mutation. To accept the theory of revolution, we accept these two premises. Without fitness being an aspect of survival, I’m curious what counter arguments there are out there to the position that we really are always getting dumber. I’ll avoid the easy target of anecdotal evidence.

[after_care]

1. IQ tests are actually showing higher scores over time. About 90 years of data on this.

2. We do not have genetic data to show that these mutations are happening. This is theory only without empirical data.

3. There's a lot of debate over the role of genetics and intelligence. It's very possible that our understanding and implementation of childhood development has a larger impact on intelligence than these presumed random mutations.

4. Intelligent people are more likely to pair with other intelligent people, so maybe there is still selection effect for intelligence. This effect could be increases as world travel means a greater geographic range for potential mates.

[kovek]

> It's very possible that our understanding and implementation of childhood development has a larger impact on intelligence than these presumed random mutations.

Bones from burial sites of past hunter-gatherer societies are associated with larger jaws and mouths, while bones retrieved from former farming cultures have decreased jaw size. [0]

I believe jaw development has effects on mental health. Thus, I think our non-genetic changes do happen to affect our mental capabilities. There must be other factors than jaw size that do so.

[0] https://en.wikipedia.org/wiki/Human_jaw_shrinkage?wprov=sfti...

[pshc]

I believe it. I read the pop sci book “Breath” recently—as I remember it says jaw development has degraded in modern humans because of the availability of soft foods and increased mouth breathing. We need to chew to develop properly. Apparently this impacts the sinuses and airway which causes sleep apnea and other respiratory issues, leading to bad sleep and worsened cognition overall.

[after_care]

> I believe jaw development has effects on mental health.

Why? I am honestly curious.

[irrational]

Someone else posted around the same time as you. Apparently it has been postulated that decreased oxygen to the brain and being tired (from sleep apnea related to jaw development) causes cognitive impairment. So... give everyone a CPAP machine to sleep with?

[johnwalkr]

If you go down the rabbit hole of weird libertarian beliefs, you may stumble upon “mewing” sometime after paleo diets and nofap.

[CryptoPunk]

To a visiting alien, libertarian associated beliefs would look positively sane compared to numerous mainstream practices, like daily consumption of highly processed foods coupled with little physical activity, factory farming of meat, mono-crop agriculture, and the rituals of social sensitivity signalling that change by the year, ranging from personalized gender pronouns to micro-aggression avoidance.

It's important to note that the aforementioned are all extremely mainstream, with leading academic and corporate institutions adopting and promoting them.

[rubidium]

Yes and cranial measurements determine intelligence too…

Come on people. We’ve been down this road before. It’s not good.

[contingencies]

The Turing test is like saying planes don't fly unless they can fool birds into thinking they're birds. - Peter Norvig, via https://github.com/globalcitizen/taoup

IMHO other intelligence tests are the same - they tend to measure familiarity with established systems of rationality and response within a given culture only.

Here's a thought experiment. Imagine a student who can't read, or who can't read the language the test is written in, or are an elementary learner of that language. They would tend to score poorly. All communication is like this, not just written tests. But the logical basis upon which rationality is measured within said tests is also a language, and its drawbacks exactly parallel that of language itself. Perhaps what IQ and similar metrics are really measuring is cultural indoctrination and familiarity as a highly tangential proxy to the basic cognitive abilities which they actually purport to grade.

[imtringued]

It's impossible for there to be an objective measure of intelligence as it is an adaptation to a specific environment.

As others have said before me, an IQ test measures how adapted you are to IQ tests.

[xyzzyz]

Cranial capacity doesn’t determine intelligence, just as height doesn’t determine basketball ability. Nevertheless, good basketball players tend to be tall, and intelligent people tend to have large cranial capacity. These are well documented correlations, with multiple studies observing those.

[inglor_cz]

So, does evolution and biology stop at the neck somehow?

Or if it does not, are we better off staying ignorant than trying to discover some knowledge, however fractional and incomplete?

I don't believe in either.

[impossiblefork]

It used to be that way, but IQ has actually been dropping in Europe for quite some time. In France and the UK it's a drop of about 4 IQ points per decade, which is a bit of a crisis (some scores can be found compiled here: https://www.researchgate.net/publication/309330272_The_negat...).

There's a claim that the reversal of the Flynn effect is environmental (https://www.pnas.org/doi/10.1073/pnas.1718793115), by two Norwegian researchers, but they've argued in a way which is obviously fallacious-- they basically said that environmental effects explain the drop in Norway, but the drop in Norway is relatively low, around 1 IQ point per decade (although that is of course incredibly bad) and the argue that this is the case for the other countries as well, but that doesn't follow since the drops in the countries they do not even consider are so much larger. In fact, they could have made another argument, for example that the drops in the UK and France can't be environmental because those effects in Norway can only be made to account for one 1 IQ point per decade.

[whatshisface]

As for 2 we absolutely do have data. People are constantly being shuffled both up and down from their parents, that's why wealth is not permanently intergenerational even in a capitalist society with inheritance. De novo genetic diseases are also constantly arising from healthy parents.

[robwwilliams]

And off we go on a wild HN tangent on human intelligence.

[BarryMilo]

I have a bachelor's in psychology and almost all the comments I read are wildly speculative if not outright debunked. For some reason people think being smart means they are qualified to talk about intelligence. It does not.

[dclowd9901]

How is this a helpful comment?

[StanislavPetrov]

>There is 1) survival of the fittest and 2) random genetic mutation.

There is 1) survival of the fittest and 2) random genetic mutation and 3) survival of the luckiest.

You could be part of the fittest, most well-evolved tribe of people on the planet that gets hit by a meteor which completely obliterates your entire lineage, while a much less "fit" group of people on the other side of the world soldiers on. These survivors didn't survive the meteor strike because of any inherent strengths or benefits of evolution or genetic mutation, but they are the only ones left out of sheer chance.

[gumby]

The definition of “fitness” is context (environment) dependent. Intelligence (more than say 2s out) might not have any special advantage at the moment.

I have no opinion on this topic, merely pointing out the mechanism.

[imtringued]

I don't know why people harp on about intelligence. There are plenty stories about ugly ducklings. If you are in the wrong place (geographically, socially) and time your intelligence can mean very little.

If intelligence were some super drug every life form and human would evolve to maximize it. As an extreme example, Koalas evolved to have extremely energy efficient brains that are as small as possible.

Having a powerful "CPU" is worth very little when it is mostly empty and idle most of the time. We send our kids to the program loader (school) for 12 years for a reason. It takes a lot of effort to get the most out of our brains.

People aren't getting dumber. They are getting more isolated and out of touch with the old way of living that was considered the only way 500 years ago. A lot more people are living a lifestyle that used to be associated with aristocracy. More children are being sheltered from the outside world.

[CPLX]

It’s not really survival of the fittest, since fittest is a tautology.

It’s basically survival of the survivors.

Or, in other words, we are definitely selecting for and against certain kinds of intelligence differently now than thousands of years ago.

The better or worse element is a judgment call. But definitely different.

[dclowd9901]

Sure, but this seems more of an observation at the micro level. At the macro level, general positives (intelligence, strength, health) would generally mean more selection in their favor _overall_ wouldn’t it?

[dalbasal]

Evolution can't be tested like this, imo. You can't reason about what where it will lead and assume that this is where it's leading.

[Ekaros]

I would say that we are or were close to average peak. Just due to access to sufficient number of calories. In many parts of West that really wasn't true in relatively recent past like beginning of last century.

[dalbasal]

That may be true, but is tangential to parent's point. The point was that smart people existed, not that the median or average intelligence was higher.

It's about how their geniuses compared to ours, not how our average Joe compares to theirs.