Very often, however, ignorance of the way to learn, more than the effort of learning itself, breaks the spirit of men who are both studious and anxious to do so. So let us explain how we should become learned in this art. The fundamental principle will be that all the steps of learning should be sought from Nature: the means of perfecting our art will be found in diligence, study and application.

Leon Battista Alberti -On Painting