When you put your hand in a flowing stream, you touch the last that has gone before and the first of what is still to come.

It is an acknowledged fact that we perceive errors in the work of others more readily than in our own.

Make an effort to collect the good features from many beautiful faces.

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

Nothing is more apt to deceive us than our own judgment of our work. We derive more benefit from having our faults pointed out by our enemies than from hearing the opinions of friends.

A painter should begin every canvas with a wash of black, because all things in nature are dark except where exposed by the light.

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.