WHAT IS DEJA VU?
We have all some experience of a feeling that comes over us occasionally of what we are saying and doing having been said and done before, in a remote time--of our having been surrounded, dim ages ago, by the same faces, objects, and circumstances--of our knowing perfectly what will be said next, as if we suddenly remembered it.
(Dickens, 1850, Ch. 39).
What is deja vu? For the layperson, it is, technically, the "as if" experience, as if I have "already seen" it before. But in reality, it is far broader. So, deja vu may literally mean already seen, bur it can also mean already heard, already met, already visited, and numerous other "already" experiences. It is not "I have done it before and I know exactly when; I recognize that I'm doing it again." The reason why that is not deja vu is because the recognition is consequent on a real familiarity, whereas with deja vu, the familiarity is inappropriate--it doesn't fit.
The formal, recognized scientific definition of deja vu, which has become accepted world-wide, appears to be quoted in every major article on the subject and derives from my own PhD (Med) thesis at the University of Witwatersrand, Johannesburg, South Africa (Neppe, 1981c). Deja vu is "any subjectively inappropriate impression of familiarity of the present experience with an undefined past." The definition was reflected in my 1983 book The Psychology of Deja Vu: Have I Been Here Before? (Neppe, 1983h). Every one of these words is relevant and the definition will be revisited throughout this paper.
When Was Deja Vu First Described?
Deja vu goes back a long time and the historical landmarks are worth noting: Pythagoras 2400 years ago supposedly described the phenomenon, which was also reported by Ovid some 400 years later (Funkhouser, 2006). St. Augustine (416/2002) was responsible for the first explanation of deja vu some 1600 years ago, when he said it was due to some deceitful spirits. The first book referring to this phenomenon, describing it even before David Copperfield, though not yet naming it, was Sir Walter Scott's (1815) Guy Mannering. A poet also described the phenomenon during the mid-19th century--Dante Gabriel Rossetti in his 1854 poem Sudden Light (Schacter, 2001). The first attempt at scientific explanation of this phenomenon comes from A. L. Wigan (1844) in his book Duality of the Mind, in which he explained the phenomenon as delays in the different functions of the cerebral hemispheres. The first thesis on the subject was French, from Bernard-Leroy (1898).
When Did the Term Deja Vu Officially Arrive?
It derives from France in the late 19th century, and books will tell you the official name was given by E L. Arnaud (1896). (Try as we may, we cannot locate Arnaud's first name). Arnaud described it as sensation du deja vu and argued that it was distinct from other memory distortions, as it was just a bad judgment--misattributing the current to the past (Schacter, 2001). But in fact, 20 years earlier, Emile Boirac (1876) described le sentiment du deja vu. A string of French writers--Boirac, Arnaud, Ribot, Fouillee, Lalande, Ferenczi, Ribot, Loti, Gilles, Kindberg, Mere, Dugas, Le Lorrain, and Leroy--all used the term, consolidating its appeal (Neppe, 1983d). This was important because there had been a debate of the idea in an 1893 special issue of Revue Philosophique of whether one paramnesia alone existed (Dugas, 1894; Lalande, 1893).
In the meantime there were some alternative "pretender" terms deriving from recognition of false memory, or false recognition by leading pioneering psychologists and philosophers: Bernard-Leroy, Biervliet, Dugas, Freud, Heymans, and Laurent all referred to it as fausse reconnaissance or fausse memoire (Arnaud, 1896; Dugas, 1894; Funkhouser, 2006; Neppe, 1983h). Henry Bergson (1908), who pioneered a great deal in terms of parapsychological thinking, called it souvenir du present, and Bourdon came back to it, calling it reconnaissance des phenomenes nouveaux. …