An enormous amount of scientific language is metaphorical. We talk about a genetic code, where code originally meant a cipher; we talk about the solar system model of the atom as though the atom were like a sun and moon and planets.

Some people think that evolutionary psychology claims to have discovered that human nature is selfish and wicked. But they are flattering the researchers and anyone who would claim to have discovered the opposite. No one needs a scientist to measure whether humans are prone to knavery. The question has been answered in the history books, the newspapers, the ethnographic record, and the letters to Ann Landers. But people treat it like an open question, as if someday science might discover that it's all a bad dream and we will wake up to find that it is human nature to love one another.

Sex and excretion are reminders that anyone's claim to round-the-clock dignity is tenuous. The so-called rational animal has a desperate drive to pair up and moan and writhe.

I do look for openings where I can overturn popular misconceptions, but unlike Christopher Hitchens, I am neither a contrarian nor a lone heretic. I like to have a significant number of academics watching my back.

The costs of an ignorance of science are nor just practical ones like misbegotten policies, forgone cures, and a unilateral disarmament in national competitiveness. There is a moral cost as well. It is an astonishing fact about our species that we understand so much about the history of the universe. the forces that make it tick, the stuff it's made of; the origin of living things, and the machinery of life. A failure to nurture this knowledge shows a philistine indifference to the magnificent achievements humanity is capable of; like allowing a great work of art to molder in a warehouse.

Why is it surprising that scientists might have long hair and wear cowboy boots? In fields like neuroscience, where the events you are recording are so minute, I suspect scientists cultivate a boring, reliable image. A scientist with a reputation for flamboyance might be suspect.

Morality, then, is not a set of arbitrary regulations dictated by a vengeful deity and written down in a book; nor is it the custom of a particular culture or tribe. It is a consequence of the interchangeability of perspectives and the opportunity the world provides for positive-sum games.