The way to get a trait to spread throughout a population is with selection pressure: making those who have the trait more successful than those who do not. Positive or negative selection will both work.
If you want to teach people something, put them in a situation where they need to know it to accomplish some goal. They *will* figure it out.
"Critical thinking" seems to be the trait that is most needed by our modern citizenry, if we want to make the world a better place.
So we just need to figure out some way of making basic critical thinking skills correlate with success in some widely desirable context... Right?
EDIT: Please note, I'm not talking about removing "stupid" from the gene pool -- that's something that other people brought up in the comments section, and frankly, although I made a couple jokes about it, it's a lousy idea on a number of fronts. All I said was, it seems to me like we need more "critical thinking" going on, and the way to get that is to somehow reward that with success. Okay? Okay.
