A philosophy rejecting universal truths or ethical systems including Christianity, its ideas are traced to late 19th Century Danish writer, Soren Kierkegaard, and carried forward in France by Jean Paul Sartre and Albert Camus. The underlying idea is that responsibility for ethical behavior is placed on the individual. This assertion was especially popular with people disillusioned by World War II. In the 1940s and 1950s, Existentialism was widespread in the visual arts because artists felt the need to impose their own self expression of order in the face of chaos. American artist Robert Motherwell expressed these ideas in his paintings, which he described as "ordered chaos". Existentialism influences much American modernist painting including Abstract Expressionism, Bay Area Figurative, and Expressionism. Source: Robert Atkins, "Art Speak"<br><br>An anti-rationalist philosophical tendency and attitude to life concerned with the being or existence of the free individual in an absurd or meaningless universe. Existentialism has had many variants, but its most prominent spokesmen have been S?ren Kierkegaard (Danish, 1813-1855) and Jean-Paul Sartre (French, 1905-1980).An example of work influenced by existentialism: Alberto Giacometti (Swiss, 1901-1966), The Nose, 1947, plaster on metal, suspended by synthetic string within a metal structure, 81.5 x 66 x 36.7 cm, Centre Georges Pompidou, Paris. Alberto Giacometti was a Surrealist and a friend of Sartre&#39;s. See angst.Also see angst, Dada, isms and -ism, motivation, and Surrealism.