KANDINSKY'S DEFINITION OF HALLUCINATIONS

In 1881 the Russian psychiatrist Victor Kandinsky (1849-1889) defined hallucinations as "the stimulation of central perceptual areas, independently of direct exogenous impressions, as a result of which a perceptual image is created which, despite its subjective origin, renders the same impression of objectivity (liveliness) or realness within the consciousness of the person at hand that in ordinary circumstances accompanies the perceptual images of direct, objective perception."

Kandinsky, V. (1881). Zur Lehre von den Halluzinationen.Archiv für Psychiatrie und Nervenkrankheiten, 11, 453-464.