Theory and fact are equally strong and utterly interdependent; one has no meaning without the other. We need theory to organize and interpret facts, even to know what we can or might observe. And we need facts to validate theories and give them substance.

If there is any consistent enemy of science, it is not religion, but irrationalism.

Our creationist detractors charge that evolution is an unproved and unprovable charade — a secular religion masquerading as science. They claim, above all, that evolution generates no predictions, never exposes itself to test, and therefore stands as dogma rather than disprovable science. This claim is nonsense.

The invalid assumption that correlation implies cause is probably among the two or three most serious and common errors of human reasoning.

History does include aspects of directionality, and the present range of causes and phenomena does not exhaust the realm of past possibilities.

Wind back the tape of life to the early days of the Burgess Shale; let it play again from an identical starting point, and the chance becomes vanishingly small that anything like human intelligence would grace the replay.

No one-liner can ever be optimal.