Base and crafty cowards are like the arrow that flieth in the dark.

Before I start painting I have a slightly ambiguous feeling: happiness is a special excitement because unhappiness is always possible a moment later.

But we may go further, and affirm most truly, that it is a mere and miserable solitude to want true friends; without which the world is but a wilderness.

An artist must learn to be nourished by his passions and by his despairs.

I want a very ordered image, but I want it to come about by chance.

A man that is young in years may be old in hours if he have lost no time.

For first of all we must prepare a Natural and Experimental History, sufficient and good; and this is the foundation of all; for we are not to imagine or suppose, but to discover, what nature does or may be made to do.