In all mammalian species that have so far been carefully studied, the rate at which their members engage in the killing of conspecifics is several thousand times greater than the highest homicide rate in any American city.

There may be things that are completely unknowable to us, so we must be careful not to treat the limits of our knowledge as sure guides to the limit of what there is.

In order to make a perfect and beautiful machine, it is not requisite to know how to make it. All the works of human genius can be understood in the end to be products of a cascade of generate-and-test procedures that are, at bottom, algorithmic and mindless.

... there could be talking bunny rabbits, spiders who write English messages in their webs, and for that matter, melancholy choo-choo trains. There could be, I suppose, but there aren't-so my theory doesn't have to explain them.

If the concept of consciousness were to fall to science, what would happen to our sense of moral agency and free will? If conscious experience were reduced somehow to mere matter in motion, what would happen to our appreciation of love and pain and dreams and joy? If conscious human beings were just animated material objects, how could anything we do to them be right or wrong?

As every scuba diver knows, panic is your worst enemy: when it hits, your mind starts to thrash and you are likely to do something really stupid and self-destructive.

The earth has grown a nervous system, and it's us.