It is no small benefit on finding oneself in bed in the dark to go over again in the imagination the main lines of the forms previously studied, or other noteworthy things conceived by ingenious speculation.

I am never weary of being useful... In serving others I cannot do enough. No labor is sufficient to tire me.

The eye - which sees all objects reversed - retains the images for some time.

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.

When the thing taken into union is perfectly adapted to that which receives it, the result is delight and pleasure and satisfaction.

To speak ill of a good person is not truly good, all in all.

No human investigation can claim to be scientific if it doesn't pass the test of mathematical proof.