These words refer to a preoccupation and concern only for oneself. Egoism and egotism are a related pair with a fine distinction in meaning. Egotism is disapproving in tone, suggesting someone with an inflated or unrealistic view of his own worth because of extreme self-preoccupation: the typical egotism of those who think the world owes them a living. Egoism , on the other hand, is a more ambiguous term. It might apply to someone who does not necessarily consider himself superior but who nevertheless remains preoccupied exclusively with himself: the egoism of the young office executive seeking advancement. The word has been given a new slant of meaning, furthermore, by psychological theorists of the last half-century. Theories that stress the importance of a strong ego (or "positive self-concept") as a key to mental stability have made it possible for egoism to suggest healthy self-interest coupled with a solid sense of identity: the egoism normal to a small infant; activities that will develop a healthy egoism in young adolescents.

Conceit and vanity stress the sense of inflated worth that is involved in egotism . Conceit suggests a general state of being puffed-up about one’s own imagined superiority to others, so extreme as to rule out any self-assessment or self-criticism whatsoever: a fathomless conceit that prevents him from working hard enough to perfect his real but unformed talents. Vanity suggests self-pride that is based not so much on a feeling of superiority to others as on an unrealistic admiration and love for oneself: the actress who requires constant obeisance and flattery to satisfy her vanity . Conceit no longer sounds as extremely informal as it once may have, but vanity is still the slightly more formal of the two words. Self-importance is closely related to conceit and vanity but is more neutral and descriptive: diplomats who bustled about in a display of their own self-importance . Sometimes, the word can suggest considerations of status or involvement in serious or worthwhile affairs rather than a strictly personal conceit.

• She spends hours before her mirror feeding her vanity, but is that nay worse than your tedious concern with office protocol simply as a way of ensuring your own self-importance ?

Narcissism and solipsism may once have been technical terms drawn respectively from psychology and philosophy, but they are now gaining a wider currency for the cluster of meanings discussed here. Narcissism in a strict psychological sense refers to an extreme withdrawal into self-preoccupation and self-love. It has come to be used more loosely to substitute for egotism : the star system in the theatre that is responsible for a most pernicious form of narcissism among actors. Solipsism in a strict philosophical context refers to a disbelief in the existence of anything beyond the self; it now extends pejoratively to anyone completely wrapped up in a private world of his own: the solipsism of those avant-garde writers who do not even attempt to communicate with their audiences.

Selfishness need not suggest an inflated sense of worth at all or even extreme self-preoccupation. Its main connotation is that of grasping greediness without concern for others: the selfishness of those lobbyists who press for legislation beneficial to special interests but harmful to the general public. Under certain circumstances, however, it need not be wholly pejorative; in this it may approach come uses of egoism: the natural selfishness of the three-year-old.