Retirement savings is probably behavioral economists' greatest success story. It is a prototypical behavioral-economics problem because saving for retirement is cognitively hard - figuring out how much to save - and requires self-control.

Credit cards have been extremely profitable to banks. They're profitable not from the fees they collect from the retailers that use the credit cards, that pays the bills, but the real profits come from the interest payments and the charges to users that are unexpected.

I don't go by the ratings. I buy wine that tastes good. Statistically, anybody's ability to predict what will be a good wine a decade from now is limited.

So the world is much more correlated than we give credit to. And so we see more of what Nassim Taleb calls "black swan events" - rare events happen more often than they should because the world is more correlated.

A good rule of thumb is to assume that everything matters.

When an economist says the evidence is "mixed," he or she means that theory says one thing and data says the opposite.

It turns out, that men, when they're taking care of their business, they're not fully attending to the task at hand, but, I'm sure there's an evolutionary explanation for this, if you give them a target, they will aim.