Cognitive psychology has shown that the mind best understands facts when they are woven into a conceptual fabric, such as a narrative, mental map, or intuitive theory. Disconnected facts in the mind are like unlinked pages on the Web: They might as well not exist.

As individual people, embedded in our daily lives, of course we're interested in what makes one person different from another. We've got to hire one person and not another, marry one person and not another.

I think the reason that swearing is both so offensive and so attractive is that it is a way to push people's emotional buttons, and especially their negative emotional buttons. Because words soak up emotional connotations and are processed involuntarily by the listener, you can't will yourself not to treat the word in terms of what it means.

The human moral sense can excuse any atrocity in the minds of those who commit it, and it furnishes them with motives for acts of violence that bring them no tangible benefit.

Gossip is certainly one of the things that language is useful for, because it's always handy to know who needs a favor, who can offer a favor, who's available, who's under the protection of a jealous spouse. And being the first to get a piece of gossip is like engaging in insider trading: You can capitalize on an opportunity before anyone else can.

The task of evolutionary psychology is not to weigh in on human nature, a task better left to others. It is to add the satisfying kind of insight that only science can provide: to connect what we know about human nature with the rest of our knowledge of how the world works, and to explain the largest number of facts with the smallest number of assumptions.

I spent 20 years doing research on regular and irregular verbs, not because I'm an obsessive language lover but because it seemed to me that they tapped into a fundamental distinction in language processing, indeed in cognitive processing, between memory lookup and rule-driven computation.