"Nicholas Humphrey, a Cambridge psychologist, was the first to see clearly the solution to this puzzle. We use our intellects not to solve practical problems, but to outwit each other. Deceiving people, detecting deceit, understanding people's motives, manipulating people -these are what the intellect is used for. So what matters is not how clever and crafty you are, but how much cleverer and craftier than other people. The value of intellect is infinite. Selection within the species is always going to be more important than selection between the species."

“As every bird-watcher knows, the beauty of a bird's song is inversely correlated with the colourfulness of its plumage.”

“...compare mankind with other animals that share our highly social habits: with colonial birds, monkeys and dolphins. As we shall see, the lesson they teach is that we are designed for a system of monogamy plagued by adultery.”

“Life is a Sisyphean race, run ever faster towards a finishing line that is merely the start of the next race.”

“People are attracted to people of high reproductive and genetic potential -the healthy, the fit and the powerful. The consequences of this fact, which goes under the name of sexual selection, are bizarre in the extreme.”

“Evolving is not a goal but a means to solving a problem.”

“In behavior, as in appearance, every human individual is unique.”