The first part of Sense and Non-Sense, "Arts," is concerned with Merleau-Ponty's concepts of perception, which were advanced in his major philosophical treatise, Phenomenology of Perception. Here the analysis is focused and enriched in descriptions of the perceptual world of Cezanne, the encounter with the Other as expressed in the novels of Simone de Beauvoir and Sartre, and the gestalt quality of experience brought out in the film art form. In the second part, "Ideas," Merleau-Ponty shows how the categories of the phenomenology of perception can be understood as an outgrowth of the behavioral sciences and how a model of existence based on perception sensitizes us to the insights and limitations of previous philosophies and suggests constructive criticisms of contemporary philosophy. The third part, "Politics," clarifies the political dilemmas facing intellectuals in postwar France.