Take an arrow, and hold it in flame for the space of ten pulses, and when it cometh forth you shall find those parts of the arrow which were on the outsides of the flame more burned, blacked, and turned almost to coal, whereas the midst of the flame will be as if the fire had scarce touched it. This is an instance of great consequence for the discovery of the nature of flame; and sheweth manifestly, that flame burneth more violently towards the sides than in the midst.

No artist knows in his own lifetime whether what he does will be the slightest good, because it takes at least seventy-five to a hundred years before the thing begins to sort itself out.

Praise from the common people is generally false, and rather follows the vain than the virtuous.

Aristotle... a mere bond-servant to his logic, thereby rendering it contentious and well nigh useless.

Another argument of hope may be drawn from this-that some of the inventions already known are such as before they were discovered it could hardly have entered any man's head to think of; they would have been simply set aside as impossible. For in conjecturing what may be men set before them the example of what has been, and divine of the new with an imagination preoccupied and colored by the old; which way of forming opinions is very fallacious, for streams that are drawn from the springheads of nature do not always run in the old channels.

There is no secrecy comparable to celerity.

I loathe my own face, and I've done self-portraits because I've had nobody else to do.