“You try to understand human behavior. You try to explain it. Not me. I know we're smaller than gorillas, bigger than chimps, worse than both of them and, for all our rationality, our rules and laws, our baser drives are still straight out of the jungle.”

“Everything smaller than Heaven bores us because only Heaven is bigger than our hearts.”

“And I thought how sad it was that, for all our sophisticated intellect, for all our noble aspirations, our aggressive behavior was not just similar in many ways to that of the chimpanzees – it was even worse. Worse because human beings have the potential to rise above their baser instincts, whereas chimpanzees probably do not.”

“More than ambition, more than ability, it is rules that limit contribution; rules are the lowest common denominator of human behavior. They are a substitute for rational thought.”

“Being both more systematically brutal than chimps and more empathetic than bonobos, we are by far the most bipolar ape. Our societies are never completely peaceful, never completely competitive, never ruled by sheer selfishness, and never perfectly moral.”

“Love measures our stature: the more we love, the bigger we are. There is no smaller package in all the world than that of a man all wrapped up in himself.”