We begin, in all probability, by telling the youth of fifteen or sixteen, that Nature is full of faults, and that he is to improve her; but that Raphael is perfection, and that the more he copies Raphael the better; that after much copying of Raphael, he is to try what he can do himself in a Raphaelesque, but yet original, manner: that is to say, he is to try to do something very clever, all out of his own head, but yet this clever something is to be properly subjected to Raphaelesque rules, is to have a principal light occupying one seventh of its space, and a principal shadow occupying one third of the same; that no two people's heads in the picture are to be turned the same way, and that all the personages represented are to possess ideal beauty of the highest order, which ideal beauty consists partly in a Greek outline of nose, partly in proportions expressible in decimal fractions between the lips and chin; but partly also in that degree of improvement which the youth of sixteen is to bestow upon God's work in general. This I say is the kind of teaching which through various channels, Royal Academy lecturings, press criticisms, public enthusiasm, and not least by solid weight of gold, we give to our young men. And we wonder we have no painters!

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For it is always to be remembered that no one mind is like another, either in its powers or perceptions; and while the main principles of training must be the same for all, the result in each will be as various as the kinds of truth which each will apprehend; therefore, also, the modes of effort, even in men whose inner principles and final aims are exactly the same.

John Ruskin Pre-Rafaelitism 1851