The hypotheses we accept ought to explain phenomena which we have observed. But they ought to do more than this: our hypotheses ought to foretell phenomena which have not yet been observed.

Those who have obtained the farthest insight into Nature have been, in all ages, firm believers in God.

The catastrophist constructs theories, the uniformitarian demolishes them.

Fundamental ideas are not a consequence of experience, but a result of the particular constitution and activity of the mind, which is independent of all experience in its origin, though constantly combined with experience in its exercise.

Prudence supposes the value of the end to be assumed, and refers only to the adaptation of the means. It is the relation of right means for given ends.

It is a test of true theories not only to account for but to predict phenomena.

Every failure is a step to success.