A thought once awakened does not again slumber.

One must verify or expel his doubts, and convert them into the certainty of Yes or NO.

If a book comes from the heart, it will contrive to reach other hearts; all art and author-craft are of small amount to that.

Everywhere in life, the true question is not what we gain, but what we do.

Neither had Watt of the Steam engine a heroic origin, any kindred with the princes of this world. The princes of this world were shooting their partridges... While this man with blackened fingers, with grim brow, was searching out, in his workshop, the Fire-secret.

The past is always attractive because it is drained of fear.

Learn to be good readers, which is perhaps a more difficult thing than you imagine. Learn to be discriminative in your reading; to read faithfully, and with your best attention, all kinds of things which you have a real interest in,--a real, not an imaginary,--and which you find to be really fit for what you are engaged in.