Vanity is the excessive belief in one's own abilities or attractiveness to others. Prior to the fourteenth century it didn't have such narcissistic undertones, and merely meant futility. The related term vainglory is now often seen as an archaic synonym for vanity, but originally meant boasting in vain, i.e. unjustified boasting; although glory is now seen as having an exclusively positive meaning, the Latin term gloria (from which it derives) roughly means boasting, and was often used as a negative criticism.

In religion and philosophy

In this painting Daydreams by Thomas Couture, the vice of vanity is shown through a boy blowing bubbles. The Walters Art Museum.

In a large number of religions, vanity, in its modern sense, is considered a form of self-idolatry, in which one likens their self to the greatness of God for the sake of their own image, and thereby becomes separated and perhaps in time divorced from the Divine grace of God. In Christian teachings vanity is considered an example of pride, one of the seven deadly sins.

Philosophically speaking, vanity might refer to a broader sense of egoism and pride. Friedrich Nietzsche wrote that "vanity is the fear of appearing original: it is thus a lack of pride, but not necessarily a lack of originality." One of Mason Cooley'saphorisms is "Vanity well fed is benevolent. Vanity hungry is spiteful."

Symbolism

In Western art, vanity was often symbolised by a peacock, and in Biblical terms, by the Whore of Babylon. During the Renaissance, vanity was invariably represented as a naked woman, at times seated or reclining on a couch. She attends to her hair with comb and mirror. The mirror is at times held by a demon or a putto. Symbols of vanity include jewels, gold coins, a purse, and often by the figure of death himself.

Often we find an inscription on a scroll that reads Omnia Vanitas ("All is Vanity"), a quotation from the Latin translation of the Book of Ecclesiastes. Although that phrase, itself depicted in a type of still life, vanitas (Latin, "emptiness"), originally referred not to obsession with one's appearance, but to the ultimate fruitlessness of humankind's efforts in this world, the phrase summarises the complete preoccupation of the subject of the picture.

"The artist invites us to pay lip-service to condemning her," writes Edwin Mullins, "while offering us full permission to drool over her. She admires herself in the glass, while we treat the picture that purports to incriminate her as another kind of glass—a window—through which we peer and secretly desire her." The theme of the recumbent woman often merged artistically with the non-allegorical one of a reclining Venus.

In his table of the Seven deadly sins, Hieronymus Bosch depicts a bourgeois woman admiring herself in a mirror held up by a devil. Behind her is an open jewellery box. A painting attributed to Nicolas Tournier, which hangs in the Ashmolean Museum, is An Allegory of Justice and Vanity. A young woman holds a balance, symbolising justice; she doesn't look at the mirror or the skull on the table before her. Vermeer's famous painting Girl with a Pearl Earring is at times believed to depict the sin of vanity, as the young girl has adorned herself before a glass without further positive allegorical attributes.

All is Vanity, by Charles Allan Gilbert (1873–1929), carries on this theme. An optical illusion, the painting depicts what appears to be a large grinning skull. Upon closer examination, it reveals itself to be a young woman gazing at her reflection in the mirror. In the film The Devil's Advocate, Satan (Al Pacino) claims that "vanity is his favourite sin".

Such artistic works served to warn viewers of the ephemeral nature of youthful beauty, as well as the brevity of human life and the inevitability of death.