"People will often make the case, 'We can't be that stupid, or we would have been evolutionarily wiped out as a species a long time ago.' I don't agree. I find myself saying, 'Well, no. Gee, all you need to do is be far enough along to be able to get three square meals or to solve the calorie problem long enough so that you can reproduce. And then, that's it. You don't need a lot of smarts. You don't have to do tensor calculus. You don't have to do quantum physics to be able to survive to the point where you can reproduce.' One could argue that evolution suggests we're not idiots, but I would say, 'Well, no. Evolution just makes sure we're not blithering idiots. But, we could be idiots in a lot of different ways and still make it through the day.'"
-Cornell professor of social psychology David Dunning talks to Errol Morris about what we know, what we don't know, and what we don't know we don't know. It sounds complicated, but it's pretty fascinating.