Let not your rage or malice destroy a life.
Whoever in debate quotes authority uses not intellect, but memory.
A good painter has two main objects to paint, man and the intention of his soul.
No human investigation can claim to be scientific if it doesn't pass the test of mathematical proof.
The boundaries of bodies are the least of all things.
When you are painting you should take a flat mirror and often look at your work within it, and it will then be seen in reverse, and will appear to be by the hand of some other master, and you will be better able to judge of its faults than in any other way.