We inhabit a complex world. Some boundaries are sharp and permit clean and definite distinctions. But nature also includes continua that cannot be neatly parceled into two piles of unambiguous yeses and noes. Biologists have rejected, as fatally flawed in principle, all attempts by anti-abortionists to define an unambiguous 'beginning of life,' because we know so well that the sequence from ovulation or spermatogenesis to birth is an unbreakable continuum-and surely no one will define masturbation as murder.

Our world is not an optimal place, fine tuned by omnipotent forces of selection. It is a quirky mass of imperfections, working well enough (often admirably); a…

Siphonophores do not convey the message-a favorite theme of unthinking romanticism-that nature is but one gigantic whole, all its parts intimately connected an…

Perhaps randomness is not merely an adequate description for complex causes that we cannot specify. Perhaps the world really works this way, and many events ar…

The total amount of suffering per year in the natural world is beyond all decent contemplation. During the minute that it takes me to compose this sentence, th…

There is one living spirit, prevalent over this world ... which assumes a multitude of forms according to subordinate laws. There is one thinking sensible prin…

We are inescapably the result of a long heritage of learning, adaptation, mutation and evolution, the product of a history which predates our birth as a biolog…