Paolo Uccello's wife told people that Paolo used to stay up all night in his study trying to work out the vanishing points of his perspective. When she called him to come to bed, he would say "Oh what a lovely thing this perspective is!"
Giorgio VasariDrawing is the necessary beginning of everything [in Art], and not having it, one has nothing.
Giorgio VasariThe best thing is to draw men and women from the nude and thus fix in the memory by constant exercise the muscles of the torso, back, legs, arms and knees, with bones underneath.
Giorgio Vasari