A major reason is, people are not actually as intelligent or creative as one assumes. We are bad at unsupervised learning. A lot of our learning, when you look more closely, is supervised learning.
This is correct; there's been a huge amount of brain evolution in the past 50K years. See for example "The 10,000 Year Explosion" (Cochran).
Furthermore, this is why Cochran is considered a racist; correctly so.
Furthermore, this is why Cochran is considered a racist; correctly so.
I'd caution that this isn't actually an argument, but merely invective: http://www.paulgraham.com/say.html