What enables painting is the perception and representation of intensity. Every point in space has different intensity, which can be represented in painting by black and white and all the gray shades between. In practice, painters can articulate shapes by juxtaposing surfaces of different intensity; by using just color (of the same intensity) one can only represent symbolic shapes. Thus, the basic means of painting are distinct from ideological means, such as geometrical figures, various points of view and organization (perspective), and symbols.
From the 1920s onward, thesurrealism movement spread around the globe, eventually affecting the visual arts, literature, film, and music of many countries and languages, as well as political thought and practice, philosophy, and social theory.