The spectator, as he walks the gallery, will stop, or pass along. To give a general air of grandeur at first view, all trifling, or artful play of little lights, or an attention to a variety of tints is to be avoided; a quietness and simplicity must reign over the whole work, to which a breadth of uniform and simple color will very much contribute.

Seven Discourses Delivered in the Royal Academy (ed. 1778)