He inquired about the geological structure of his landscapes, convinced that these abstract relationships, expressed, however, in terms of the visible world, should affect the act of painting. The rules of anatomy and design are present in each stroke of his brush just as the rules of the game underlie each stroke of a tennis match. But what motivates the painter's movement can never be simply perspective or geometry or the laws governing color, or, for that matter, particular knowledge. Motivating all the movements from which a picture gradually emerges there can be only one thing: the landscape in its totality and in its absolute fullness, precisely what Cezanne called a ‘motif’.