For successful education there must always be a certain freshness in the knowledge dealt with. It must be either new in itself or invested with some novelty of application to the new world of new times. Knowledge does not keep any better than fish. You may be dealing with knowledge of the old species, with some old truth; but somehow it must come to the students, as it were, just drawn out of the sea and with the freshness of its immediate importance.

The preternatural solemnity of a good many of the professionally religious is to me a point against them.

It is impossible to meditate on time and the mystery of nature without an overwhelming emotion at the limitations of human intelligence.

In this modern world, the celibacy of the medieval learned class has been replaced by a celibacy of the intellect which is divorced from the concrete contemplation of the complete facts.

Education with inert ideas is not only useless; it is above all things harmful.

Imagination is not to be divorced from the facts. It is a way of illuminating the facts.

True courage is not the brutal force of vulgar heroes, but the firm resolve of virtue and reason.