Chapter 12 starts with a conversation between members of two intelligent non-human species, talking about humans.
They never know anything. From earliest childhood, they delude themselves into thinking they comprehend the world, while all that's really going on is that they've got some primitive assumptions and prejudices. Individually, human beings are all dolts.
Collectively, they're a collection of dolts. But in their scurrying around and pretending to be wise, one or two of them will come up with some idea that is just a little bit closer to the truth than what was already known. And in a sort of fumbling trial and error, about half the time the truth actually rises to the top and becomes accepted by people who still don't understand it, who simply adopt it as a new prejudice to be trusted blindly until the next dolt accidentally comes up with an improvement.
So you're saying that no one is ever individually intelligent, and groups are even stupider than individuals - and yet by keeping so many fools engaged in pretending to be intelligent, they still come up with some of the same results that an intelligent species would come up with.
I like this book alot. Orson Scott Card has just described the scientific method, in a brief, clear, and hysterically funny way. The series so far is full of insights with descriptions that delicately and elegantly run roughshod all over everything.