A Treatise on Painting, by Leonardo da Vinci
Senex and Taylor, London
The great Design of a Painter, is so to manage a Plane Surface, as that on it may appear a Body rais'd and standing out from the said Plane. And he, who in this Point surpasses the rest, is the Person, to whom the Palm of his Profession, is indisputably due. Now this pitch and perfection of the Art, arising from a just and natural Dispensation of Lights and Shadows, usually express'd by the Word Clair-obscure; it follows, that a Painter, in being sparing of his Shadows, where they are necessary, does an Injury to himself; and renders both his Name and his Works contemptible in the Eyes of the knowing, purely to purchase a false Esteem among the Croud; who having no Notion of the Relievo, never mind any thing in a Painting, beyond the Glare, and Pageantry of the Colours.