Humans have a lot of pro-social tendencies.

After World War II it was decided that, in order to prevent the Germans and the French from having another war, it would be better to tie them together into one economic pact so they would invest in each other and have mutual stakes. Until now, that has worked to prevent warfare between the two.

Religion may have become a codification of morality, and it may fortify it, but it's not the origin of it.

Most exotic animals are not particularly interested in people, which makes it hard to provoke them. Human-rearing gets them used to and sometimes imprinted on humans, which makes them potentially dangerous.

Darwin wasn't just provocative in saying that we descend from the apes - he didn't go far enough. We are apes in every way, from our long arms and tailless bodies to our habits and temperament.

It is not only visitors to the zoo who are fascinated but uneasy in the presence of chimpanzees; the same is true of scientists. The more they learn about these great apes, the deeper our identity crisis seems to become. The resemblance between humans and chimpanzees is not only external. If we look straight and deep into a chimpanzee’s eyes, an intelligent, self-assured personality looks back at us. If they are animals, what must we be?

The sturdiest pillars of human morality are compassion and a sense of justice.