The way in which the persecution of Galileo has been remembered is a tribute to the quiet commencement of the most intimate change in outlook which the human race had yet encountered. Since a babe was born in a manger, it may be doubted whether so great a thing has happened with so little stir

The worst that happened to men of science was that Galileo suffered an honorable detention and a mild reproof, before dying peacefully in his bed.

There are no whole truths: all truths are half-truths. It is trying to treat them as whole truths that plays to the devil.

You cannot be wise without some basis of knowledge, but you may easily acquire knowledge and remain bare of wisdom.

Learning preserves the errors of the past as well as its wisdom.

No period of history has ever been great or ever can be that does not act on some sort of high, idealistic motives, and idealism in our time has been shoved aside, and we are paying the penalty for it.

Every philosophy is tinged with the coloring of some secret imaginative background, which never emerges explicitly into its train of reasoning.