There are some rules, whose absolute authority, like that of our nurses, continues no longer than while we are in a state of childhood. One of the first rules, for instance, that I believe every master would give to a young pupil, respecting his conduct and management of light and shadow, would be what Lionardo da Vinci has actually given; that you must oppose a light ground to the shadowed side of your figure, and a dark ground to the light side. If Lionardo had lived to see the superior splendour and effect which has been since produced by the exactly contrary conduct--by joining light to light and shadow to shadow--though without doubt he would have admired it, yet, as it ought not, so probably it would not be the first rule with which he would have begun his instructions. Again; in the artificial management of the figures, it is directed that they shall contrast each other according to the rules generally given; that if one figure opposes his front to the spectator, the next figure is to have his back turned, and that the limbs of each individual figure be contrasted; that is, if the right leg be put forward, the right arm is to be drawn back. It is very proper that those rules should be given in the Academy; it is proper the young students should be informed that some research is to be made, and that they should be habituated to consider every excellence as reducible to principles. Besides, it is the natural progress of instruction to teach first what is obvious and perceptible to the senses, and from hence proceed gradually to notions large, liberal, and complete, such as comprise the more refined and higher excellencies in Art. But when students are more advanced, they will find that the greatest beauties of character and expression are produced without contrast; nay more, that this contrast would ruin and destroy that natural energy of men engaged in real action, unsolicitous of grace. St. Paul preaching at Athens, in one of the Cartoons, far from any affected academical contrast of limbs, stands equally on both legs, and both hands are in the same attitude: add contrast, and the whole energy and unaffected grace of the figure is destroyed. Elymas the sorcerer stretches both hands forward in the same direction, which gives perfectly the expression intended. Indeed, you never will find in the works of Raffaelle any of those school-boy affected contrasts. Whatever contrast there is, appears without any seeming agency of art, by the natural chance of things. What has been said of the evil of excesses of all kinds, whether of simplicity, variety, or contrast, naturally suggests to the painter the necessity of a general inquiry into the true meaning and cause of rules, and how they operate on those faculties to which they are addressed: by knowing their general purpose and meaning he will often find that he need not confine himself to the literal sense; it will be sufficient if he preserve the spirit of the law.