Now the basic impulse behind existentialism is optimistic, very much like the impulse behind all science. Existentialism is romanticism, and romanticism is the feeling that man is not the mere he has always taken himself for. Romanticism began as a tremendous surge of optimism about the stature of man. Its aim — like that of science — was to raise man above the muddled feelings and impulses of his everyday humanity, and to make him a god-like observer of human existence.

p. 96 - Introduction to the New Existentialism (1966)