Three things are needed for success in painting and sculpture: to see beauty when young and accustom oneself to it, to work hard, and to obtain good advice.
What we have is given by God and to teach it to others is to return it to him.
There are two devices which can help the sculptor to judge his work: one is not to see it for a while. The other... is to look at his work through spectacles which will change its color and magnify or diminish it, so as to disguise it somehow to his eye, and make it look as though it were the work of another.
