The seventh, about light and shade.
The eighth, about colours, how to paint like nature.
The ninth, about the ordering (composition) of the picture.
The tenth, about free painting, which alone is made by Imagination without any other help.
III
Glad enough should we be to attain unto great knowledge without toil, for nature has implanted in us the desire of knowing all things, thereby to discern a truth of all things. But our dull wit cannot come unto such perfectness of all art, truth, and wisdom. Yet are we not, therefore, shut out altogether from all arts. If we want to sharpen our reason by learning and to practise ourselves therein, having once found the right path we may, step by step, seek, learn, comprehend, and finally reach and attain unto something true. Wherefore, he that understandeth how to learn somewhat in his leisure time, whereby he may most certainly be enabled to honour God, and to do what is useful both for himself and others, that man doeth well; and we know that in this wise he will gain much experience in art and will be able to make known its truth for our good. It is right, therefore, for one man to teach another. He that joyfully doeth so, upon him shall much be bestowed by God, from whom we receive all things. He hath highest praise.
One finds some who know nothing and learn nothing. They despise learning, and say that much evil cometh of the arts, and that some are wholly vile. I, on the contrary, hold that no art is evil, but that all are good. A sword is a sword which may be used either for murder or for justice. Similarly the arts are in themselves good. What God hath formed, that is good, misuse it how ye will.
Thou findest arts of all kinds; choose then for thyself that which is like to be of greatest service to thee. Learn it; let not the difficulty thereof vex thee till thou hast accomplished somewhat wherewith thou mayest be satisfied.
It is very necessary for a man to know some one thing by reason of the usefulness which ariseth therefrom. Wherefore we should all gladly learn, for the more we know so much the more do we resemble the likeness of God, who verily knoweth all things.
The more, therefore, a man learneth, so much the better doth he become, and so much the more love doth he win for the arts and for things exalted. Wherefore a man ought not to play the wanton, but should learn in season.