A bird is an instrument working according to mathematical law, which instrument it is within the capacity of man to reproduce with all its movements, but not with a corresponding degree of strength, though it is deficient only in the power of maintaining equilibrium. We may therefore say that such an instrument constructed by man is lacking in nothing except the life of the bird, and this life must needs be supplied from that of man.

The eye which turns from a white object in the light of the sun and goes into a less fully lighted place will see everything as dark.

Every now and then go away, have a little relaxation, for when you come back to your work your judgment will be surer. Go some distance away because then the work appears smaller and more of it can be taken in at a glance and a lack of harmony and proportion is more readily seen.

You do ill if you praise, but worse if you censure, what you do not understand.

Shadow is the diminution alike of light and of darkness, and stands between darkness and light.

I say that in narrative paintings one should mingle direct contraries close by, because they produce strong contrasts with one another, and all the more so when they are very close together; that is, the ugly next to the beautiful, the big to the small, the old to the young, the strong to the weak; in this way you will vary as much as possible and close by.

People of higher talent work, even if they seem to do nothing