I am surprised so many cling to the idea that intelligence is highly genetic when we have demonstrated before that so many things can be done to completely nullify any genetic advantage.
I am not saying there are no genetic contributions, but clearly any genetic benefit is highly contingent on many external factors.
For example, I doubt Terrance Tao would have become the genius he is today if he were raised in conditions like many children in the Romanian orphanages in the 1980s and 1990s.
> we have demonstrated before that so many things can be done to completely nullify any genetic advantage.
If the genetic advantage is nullifiable, how can it exist?
When people compare intelligence to height, they are speaking with respect to maximum potential. As far as we know, genetics do dictate how tall you can potentially become. Environmental factors may leave you shorter than your potential, but if we were able to expose all people to a perfect growing environment, they would not all end up being the exact same height. They would only grow to the limit dictated by their individual genetics.
If a supposed genetic advantage with respect to maximum intelligence potential is nullifiable, that surely implies that all humans have the capability of reaching equal intelligence? But then what genetic advantage is there to speak of?
> If the genetic advantage is nullifiable, how can it exist?
"Nullify" was a bad word to use, so thank you bringing that to my attention.
The genetic advantage is environmentally dependent. In other words, having the right genes may be necessary, but the right genes alone are not sufficient.
> they are speaking with respect to maximum potential.
And how is the maximum potential determined? Maximum potential seems to me like some kind of ethereal value based on comparative associations to others with the same/similar genes. "Feynman has these genes and was a genius. If you have these genes you should be a genius too." We both know genetics and intelligence do not work like this.
> Environmental factors may leave you shorter than your potential
Human Growth Hormones can also leave you taller than your "potential" if administered prior to your growth plates forming. So, the "potential" value is apparently not static because environmental values can increase/decrease the potential.
> people to a perfect growing environment, they would not all end up being the exact same height.
We can assume this, but we cannot possibly confirm this. Albeit, I do agree with you on this, rationally speaking.
> But then what genetic advantage is there to speak of?
The genetic advantage would be having the appropriate genes in the appropriate environment.
> having the right genes may be necessary, but the right genes alone are not sufficient.
Right, which is why the intelligence:height comparison exists at all. It is, to the best of our understanding, that the right genes are required to become eight feet tall, so to speak, but that you also need to right environment to actually get there. "8-foot genes" alone does not guarantee you will become eight feet tall, and that's what the height comparison tells.
> And how is the maximum potential determined?
I'm not sure that it is, nor does it need to be for any practical purpose.
> "Feynman has these genes and was a genius. If you have these genes you should be a genius too." We both know genetics and intelligence do not work like this.
Hence why the height comparison has been made. It is an example where environmental factors are generally accepted, and easily observed (you don't need any special tools to recognize when someone is tall) within accepted conditions.
> We can assume this, but we cannot possibly confirm this.
Well, then the assumption is good enough, isn't it? It is just a communication device anyway. It doesn't even actually have to be true so long as it effectively communicates the idea, and based on what you are saying I'm certain it does as you are echoing what it says exactly.
I think a chronic problem is people and studies starting with a false premise without even realizing it.
"Affluence is strongly correlated with higher IQ, therefore IQ is a socioeconomic problem"
You have the classic example of the smart person saying "I grew up in a house with a lot of books"
And then everyone reflexively takes away "Having lots of books around when you are young leads to more success!"
But virtually no one goes to "Smart people tend to have lots of books in their home, and they also tend to give birth to smart children, who are unsurprisingly drawn to reading books"
I am not saying there are no genetic contributions, but clearly any genetic benefit is highly contingent on many external factors.
For example, I doubt Terrance Tao would have become the genius he is today if he were raised in conditions like many children in the Romanian orphanages in the 1980s and 1990s.