“In notes for his treatise on painting, Leonardo recommended to young artists this practice of walking around town, finding people to use as models, and recording the most interesting ones in a portable notebook: “Take a note of them with slight strokes in a little book which you should always carry with you,” he wrote. “The positions of the people are so infinite that the memory is incapable of retaining them, which is why you should keep these sketches as your guides.”22.”
