Might intelligence decrease among humanity?
A common belief among members of this community seems to be that long-term, humans are likely to increase in intelligence, knowledge, and general problem-solving ability. I would like to take a moment to argue for the opposite position. This is not a strongly held belief of mine, but as I don’t think I’ve seen this argument mentioned explicitly here before, it seems worthwhile to present a steel-manned version of it.
The argument for long-term increased human intelligence tends to rest on a few broad assumptions (some of these may be contingent on each other and some may not; I am not making a strong effort to further classify these assumptions):
genetic engineering for human enhancement will become available or even commonplace in the future. This, and better understanding of mental health care in general, will likely increase average intelligence.
Current and future technology will allow for better interfacing with the world’s existing body of knowledge, leading to more informed decision-making and more effective problem-solving.
Human knowledge and useful techniques tend to build on each other from generation to generation, and will continue to do so, allowing for work “on the shoulders of giants”.
All of these possibilities seem quite likely, and I don’t wish to directly argue against any of them. However, there is a massive competing factor that may shape the evolution of humanity, which I have not yet seen discussed in any depth: population growth dynamics.
The fact of the matter is, intelligent, well-educated people don’t tend to have that many children. There are countless possible factors for this, but it seems plausible to attribute this in part to belief (smarter people tend to have atheistic, more pessimistic outlooks on the future, on average), in part to effective contraceptive usage, and in part due to work culture (“having children in *this* economy? With these work hours??”). In contrast, less intelligent people tend to have far more children. Again, the exact factors are hard to know with any confidence, but it seems like this is due in large part to taking more spontaneous risks (thereby leading to reduced likelihood of using birth control), higher religiosity (many religions hold that having as many children as possible is a Divine Mandate, regardless of how hard it is on the family), and lesser concern about long-term financial issues (“well I didn’t think of that in the moment…”). At the same time, life expectancy does not differ tremendously between more and less intelligent people, with the average life lasting far longer than most people’s reproductive age in almost all cases. It should also be pointed out that while it is the case that plenty of people born into deeply religious groups lose their faith and at least some cultural practices later in life, it is still far from the majority of people who do so.
Finally, a fairly consistent trend among highly religious groups who have a tremendous number of children seems to be a rejection of at least some technology and medical interference in early life. If it is discovered that people with some given externally-applied attribute (such as having genetically-modified characteristics) are significantly less likely to remain religious, it is extremely likely that such modifications will become highly frowned-upon in those cultures, at the very least.
Putting all of this together, it seems reasonable to assume that over significant lengths of time, both strongly religious communities and (perhaps to a lesser degree) people with lower IQ (do please note that the two factors are only statistically correlated, and there are countless counter-examples before you get angry at me) are likely to reproduce at a significantly higher rate than atheist, rationalist groups, even assuming a not insignificant percentage of people “convert” to the latter. If intelligence and/or inherited religiosity is assumed to be even slightly genetic, then we can expect the former to decrease over time, and the latter to rise over time, on average. There may certainly be groups of people with significantly raised intelligence in the future, but unless those groups either have higher reproductive rates or significantly higher “conversion” rates than religious groups which mandate lots of children, one can expect these “superhumans” to remain a minority for the foreseeable future.
I may very well be completely incorrect here, and I welcome criticism of all types. I’m using a burner account for this post for obvious reasons, so I may not respond to your comments, but rest assured I will read them. I also apologize for not sourcing my claims (some of which may be controversial), as I wrote this without internet connection and don’t have time to add them in now :/
Honestly, I don’t know, and I wish I had more data on this. On one hand, the thing that you described (also, the Idiocracy movie) sounds plausible. On the other hand, there seem to be a lot of smart people out there. How is that possible? Seems like there are some forces in the opposite direction, but I can only make a guess about what they are. And individual guess can be wrong, but the fact seems to be that there are enough smart people out there. So, here go the guesses:
You focus on the top of the bell curve; people with IQ 150+ having few kids. But if you look at the opposite end of the curve, people with IQ 50- have even fewer kids (often because they are sick and die young). Perhaps the long-term source of high intelligence is not geniuses breeding like rabbits, but the average people breeding like rabbits and once in a while randomly getting a genius child.
The religious groups can actually preserve the high-IQ genes. The smart atheists often end up childless, but the smart people growing up in a religious cult may channel their IQ into having many children and taking care of them. Also, successful cult leaders probably have higher than average intelligence.
Marital infidelity? Less intelligent fathers unknowingly bringing up children of more intelligent fathers? Here again, I think you make the mistake of only looking at academically successful people as examples of IQ, ignoring people who channel their high IQ into social skills.
Generally, I think it is the non-nerdy people with IQ about 125 who reproduce successfully a lot, and as a group happen to generate a few IQ 150+ children and grandchildren, who keep the intelligence elite existing. The IQ 150+ people are not a separate species; they are mere extremes on the continuum.
1. I think X because …, where … rests on an if.
That if is kind of important. (I haven’t seen a lot more than anecdotes...to the opposite effect.)
2.
Compare these two.
(future)
(present/past)
Refuting 3 sounds like ‘you think civilization is going to collapse’.
3.
A) What’s the number
B) Has it changed over time? Where do you think it’s going?
0.
A poll on this subject might be interesting.
Which religions does this apply to?
Is China religious? Russia?
If China was to start doing genetic experimentation, and no one else, well, what is the population of China?