Wisdom is the daughter of experience

Iron rusts from disuse; water loses its purity from stagnation... even so does inaction sap the vigor of the mind.

Experience does not err. Only your judgments err by expecting from her what is not in her power.

Affective gestures pointing to things near either in time or space should be made with the hand not very far from the body of the person pointing; and if these things are distant, the hand of the painter should be more extended and the face turned toward the person to whom he is addressing the demonstration.

Perspective is the rein and rudder of painting.

Make your work to be in keeping with your purpose

When you draw a nude, sketch the whole figure and nicely fit the members to it and to each other. Even though you may only finish one portion of the drawing, just make certain that all the parts hang together, so that the study will be useful to you in the future.