Doppelgänger

In fiction, folklore and popular culture, a doppelgänger is a tangible double of a living person that typically represents evil. In the vernacular, the word doppelgänger has come to refer to any double or look-alike of a person.

The word is also used to describe the sensation of having glimpsed oneself in peripheral vision, in a position where there is no chance that it could have been a reflection. Doppelgängers are often perceived as a sinister form of bilocation and generally regarded as harbingers of bad luck. In some traditions, a doppelgänger seen by a person's friends or relatives portends illness or danger, while seeing one's own doppelgänger is an omen of death.

Abraham Lincoln told his wife that he saw two faces of himself in a mirror soon after being elected president, one deathly pale. His wife believed this to mean he would be elected to a second term but would not survive.

Doppelgangers appear in a variety of science fiction and fantasy works, in which they are a type of shape shifter that mimics a particular person or species for some typically nefarious reason.

Doppelgängers, as dark doubles of individual identities, appear in a variety of fictional works from Fyodor Dostoyevsky’s “The Double” to Ralph Ellison’s Invisible Man. In its simplest incarnation, mistaken identity is a classic trope used in literature, from “Twelfth Night” to “A Tale of Two Cities”, by Charles Dickens. But in these cases, the characters look similar for perfectly normal reasons, such as being siblings or simple coincidence.

Some stories offer supernatural explanations for doubles. These doppelgängers are typically, but not always, evil in some way. The double will often impersonate the victim and go about ruining them, for instance through committing crimes or insulting the victim's friends. Sometimes, the double even tries to kill the original. In José Saramago’s 2001 novel The Double (original Portuguese title O Homem Duplicado), both men's baser instincts come to the surface and they attempt to take advantage of each other.