Self-righteousness (also called sanctimoniousness, sententiousness, a holier-than-thou attitude[1]) is a feeling of (usually) smug moral superiority[2] derived from a sense that one's beliefs, actions, or affiliations are of greater virtue than those of the average person.
The term "self-righteous" is often considered derogatory (see, for example, journalist and essayist James Fallows' description of self-righteousness[3] in regards 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."