He that hath knowledge spareth his words.

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.

Many a man's strength is in opposition, and when he faileth, he grows out of use.

If I go to the National Gallery and I look at one of the great paintings that excite me there, it's not so much the painting that excites me as that the painting unlocks all kinds of valves of sensation within me which return me to life more violently.

The human understanding, from its peculiar nature, easily supposes a greater degree of order and equality in things than it really finds.

Money is like muck, not good unless spread.

I regret not starting to paint earlier...It is one of the few things I do regret.