doppelgänger

doppelgänger, (German: “double goer”), in German folklore, a wraith or apparition of a living person, as distinguished from a ghost. The concept of the existence of a spirit double, an exact but usually invisible replica of every man, bird, or beast, is an ancient and widespread belief. To meet one’s double is a sign that one’s death is imminent. The doppelgänger became a popular symbol of horror literature, and the theme took on considerable complexity....