Postmodernism emerged in reaction to modernism and lacks a clear definition or origin. It encompasses developments in many fields starting in the 1940s and peaking in the 1960s-1970s. Postmodernism rejects rationality and objectivity in favor of opinion and relative morality. It is characterized by embracing the absurdity of life, losing faith in authority, and feeling alienated from society. Postmodernism deliberately mixes styles while modernism rejected conventions. Some criticisms are that postmodernism is too narrow, subordinates truth to identity, is divisive, lacks self-criticism, and has no foundation.