Medical knowledge and technical savvy are biodegradable. The sort of medicine that was practiced in Boston or New York or Atlanta fifty years ago would be as strange to a medical student or intern today as the ceremonial dance of a !Kung San tribe would seem to a rock festival audience in Hackensack.

Viewed from the distance of the moon, the astonishing thing about the earth, catching the breath, is that it is alive. ... It has the organized, self-contained look of a live creature, full of information, marvelously skilled in handling the sun

We habitually engage in meddling with nature. Until this century most of this meddling was good. Witness the preservation of the European countryside. But since then we've smoked it up and littered it and dumped too much in too many waters. I don't think it's our privilege to behave this way.

Given the opportunity, under the right conditions, two cells from wildly different sources, a yeast cell, say, and a chicken erythrocyte, will touch, fuse, and the two nuclei will then fuse as well, and the new hybrid cell will now divide into monstrous progeny. Naked cells, lacking self-respect, do not seem to have any sense of self.

All of today's DNA, strung through all the cells of the earth, is simply an extension and elaboration of [the] first molecule.

It is not so bad being ignorant if you are totally ignorant; the hard thing is knowing in some detail the reality of ignorance.

It is in our genes to understand the universe if we can, to keep trying even if we cannot, and to be enchanted by the act of learning all the way.