Try to learn something about everything and everything about something.

There is no absurdity in theology so great that you cannot parallel it by a greater absurdity in Nature.

Fact I know; and Law I know; but what is this Necessity, save an empty shadow of my own mind's throwing?

As a natural process, of the same character as the development of a tree from its seed, or of a fowl from its egg, evolution excludes creation and all other kinds of supernatural intervention.

Science is simply common sense at its best.

In scientific work, those who refuse to go beyond fact rarely get as far as fact.

The great end of life is not knowledge but action.