A word is an arbitrary label - that's the foundation of linguistics. But many people think otherwise. They believe in word magic: that uttering a spell, incantation, curse, or prayer can change the world. Don't snicker: Would you ever say, 'Nothing has gone wrong yet' without looking for wood to knock?

When time permits, I try to see interesting people in the cities I visit. In Seattle, I met Paul Allen, the co-founder of Microsoft, who is shy in personality but flamboyant in his philanthropy.

People today sometimes get uncomfortable with empirical claims that seem to clash with their political assumptions, often because they haven't given much thought to the connections.

Language is a window into human nature, but it is also a fistula, an open wound through which we're exposed to an infectious world.

Of course, genes can't pull the levers of our behavior directly. But they affect the wiring and workings of the brain, and the brain is the seat of our drives, temperaments and patterns of thought.

I have never been a fan of science fiction. For me, fiction has to explore the combinatorial possibilities of people interacting under the constraints imposed by our biology and history. When an author is free to suspend the constraints, it's tennis without a net.

We really are creatures of a violent world, biologically speaking - watching violence and learning about it is one of our cognitive drives.