Not art and science only, but patience will be required for the work.

Humor is one of the elements of genius--admirable as an adjunct; but as soon as it becomes dominant, only a surrogate for genius.

Humans fear reason, but they ought to fear stupidity- for reason can be hard, but stupidity can be fatal.

There is no surer method of evading the world than by following Art, and no surer method of linking oneself to it than by Art.

The proper place for liberality is in the realm of the emotions.

Should I not be proud, when for twenty years I have had to admit to myself that the great Newton and all the mathematicians and noble calculators along with him were involved in a decisive error with respect to the doctrine of color, and that I among millions was the only one who knew what was right in this great subject of nature?

Oh happy he who still can hope in our day to breathe the truth while plunged in seas of error! What we don't know is really what we need, and what we know is of no use to us whatever!