When crime drops dramatically in New York for no apparent reason, or when a movie made on a shoestring budget ends up making hundreds of millions of dollars - we're surprised. I'm saying, don't be surprised. This is the way social epidemics work.

I write my books to challenge my own feelings and theories. Perhaps most surprising was what I learned about rice farming. It was really interesting to think of how different Asian and Western cultures are as a result of the kinds of agricultural practices that our ancestors used for thousands of years. The life of a Chinese peasant in the Middle Ages was so dramatically different from the life of a European peasant - night and day different.

When people reflexively write checks to institutions that have billions of dollars in the bank, they are essentially committing a moral crime. Your money could do good in this world and you're choosing instead to waste it. People have to do a better job of that. You've got to find places where your money's going to do some good and direct your dollars towards that institution.

Our first impressions are generated by our experiences and our environment, which means that we can change our first impressions... by changing the experiences that comprise those impressions.

The key to good decision making is not knowledge. It is understanding. We are swimming in the former. We are desperately lacking in the latter.

And my advice for college graduates is don't reflexively give money to your alma mater, something particular to Americans that I find extraordinary. Take Princeton, for example - it has more money on a per capita basis than any educational institution in the history of educational institutions. There is no scenario where it can spend all the money its endowment generates every year. If there is anyone who gives a single dollar to Princeton, they have completely lost their mind. I will say that without reservation.

Giants are not what we think they are. The same qualities that appear to give them strength are often the sources of great weakness.