Societies that empower women are less violent in every way.

There's a common criticism of evolutionary psychology that it's fatalistic and it dooms us to eternal strife, 'Why even try to work toward peace if we're just bloody killer apes and violence is in our genes?'

Today we take it for granted that war happens in smaller, poorer and more backward countries.

An enormous amount of scientific language is metaphorical. We talk about a genetic code, where code originally meant a cipher; we talk about the solar system model of the atom as though the atom were like a sun and moon and planets.

The human capacity for compassion is not a reflex that is triggered automatically by the presence of another living thing.

Art works because it appeals to certain faculties of the mind. Music depends on details of the auditory system, painting and sculpture on the visual system. Poetry and literature depend on language.

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.