Source: Astral Codex Ten
by Scott Alexander
“The mid-20th century was the golden age of nurture. Psychoanalysis, behaviorism, and the spirit of the ‘60s convinced most experts that parents, peers, and propaganda were the most important causes of adult personality. Starting in the 1970s, the pendulum swung the other way. Twin studies shocked the world by demonstrating that most behavioral traits — especially socially relevant traits like IQ — were substantially genetic. Typical estimates for adult IQ found it was about 60% genetic, 40% unpredictable, and barely related at all to parenting or family environment. By the early 2000s, genetic science reached a point where scientists could start pinpointing the particular genes behind any given trait.” (06/26/25)
https://www.astralcodexten.com/p/missing-heritability-much-more-than