I think that communism was a major force for violence for more than 100 years, because it was built into its ideology - that progress comes through class struggle, often violent.

People have long assumed that violence is necessary for political change. Rulers never cede power voluntarily, the argument goes, so progressives have no choice but to contemplate the use of force to bring about a better world, mindful of the trade-off between a small amount of violence now and acceptance of an unjust status quo indefinitely.

'Capitalism' is a dirty word for many intellectuals, but there are a number of studies showing that open economies and free trade are negatively correlated with genocide and war.

For one thing, before the 20th century, there were plenty of genocides. We tend to forget about them, partly because they weren't as well documented and partly because, until recently, people didn't care. We used euphemisms like 'sackings' and 'sieges' instead of calling them 'genocides.'

Astrology had an important role in the ancient world. You can't understand many things unless you know something about astrology - the plays of Shakespeare and so on.

Reading is a technology for perspective-taking. When someone else's thoughts are in your head, you are observing the world from that person's vantage point.

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. Each of us is dealt a unique hand of tastes and aptitudes, like curiosity, ambition, empathy, a thirst for novelty or for security, a comfort level with the social or the mechanical or the abstract. Some opportunities we come across click with our constitutions and set us along a path in life.