If any human being earnestly desire to push on to new discoveries instead of just retaining and using the old; to win victories over Nature as a worker rather than over hostile critics as a disputant; to attain, in fact, clear and demonstrative knowlegde instead of attractive and probable theory; we invite him as a true son of Science to join our ranks.

To spend too much time in studies is sloth.

The folly of one man is the fortune of another.

Fortitude is the marshal of thought, the armor of the will, and the fort of reason.

You could say that I have no inspiration, that I only need to paint.

I foresee it and yet I hardly ever carry it out as I foresee it. It transforms itself by the actual paint. I don't in fact know very often what the paint will do, and it does many things which are very much better than I could make it do.

Nay, number itself in armies importeth not much, where the people is of weak courage; for, as Virgil saith, It never troubles the wolf how many the sheep be.