Self-righteousness (also called sanctimoniousness, sententiousness, and holier-than-thou attitudes) is a feeling or display of (usually smug) moral superiority derived from a sense that one's beliefs, actions, or affiliations are of greater virtue than those of the average person. Self-righteous individuals are often intolerant of the opinions and behaviors of others.
The term "self-righteous" is often considered derogatory (see, for example, journalist and essayist James Fallows' description of self-righteousness in regard to Nobel Peace Prize winners) particularly because self-righteous individuals are often thought to exhibit hypocrisy due to the belief that humans are imperfect and can therefore never be infallible, an idea similar to that of the Freudian defense mechanism of reaction formation. The connection between self-righteousness and hypocrisy predates Freud's views, however, as evidenced by the 1899 book Good Mrs. Hypocrite: A Study in Self-Righteousness, by the pseudonymous author "Rita."