But complex animals had obtained their adaptive flexibility at some cost--they had traded one dependency for another. It was no longer necessary to change their bodies to adapt, because now their adaptation was behavior, socially determined. That behavior required learning. In a sense, among higher animals adaptive fitness was no longer transmitted to the next generation by DNA at all. It was now carried by teaching.

All major changes are like death. You can't see to the other side until you are there.

A wonderful area for speculative academic work is the unknowable. These days religious subjects are in disfavor, but there are still plenty of good topics. The nature of consciousness, the workings of the brain, the origin of aggression, the origin of language, the origin of life on earth, SETI and life on other worlds...this is all great stuff. Wonderful stuff. You can argue it interminably. But it can't be contradicted, because nobody knows the answer to any of these topics.

One of the most difficult features of direct experience is that it is unfiltered by any theories or expectations. It's hard to observe without imposing a theory to explain what we're seeing, but the trouble with theories, as Einstein said, is that they explain not only what is observed, but what can be observed. We start to build expectations based on our theories.

Often I feel I go to some distant region of the world to be reminded of who I really am.

Personally, I don't deal much in theory. I have to deal with the facts. And on the basis of facts, I don't see much difference in the behavior of men and women.

A hundred years from now, people will look back on us and laugh. They'll say, 'You know what people used to believe? They believed in photons and electrons. Can you imagine anything so silly?' They'll have a good laugh, because by then there will be newer better fantasies... And meanwhile, you feel the way the boat moves? That's the sea. That's real. You smell the salt in the air? You feel the sunlight on your skin? That's all real. Life is wonderful. It's a gift to be alive, to see the sun and breathe the air. And there isn't really anything else.