title: Sartre's existential humanism and Freud's existential naturalism.
mesh_terms: D001527:Behaviorism; D005086:Existentialism; D005619:Freudian Theory; D049673:History, 20th Century; D006801:Humans; D001523:Mental Disorders / Q000209:etiology / Q000628:therapy; D011574:Psychoanalytic Theory; D011575:Psychoanalytic Therapy