The experiments reported in this paper originated with A. C. Voth's22,23discovery, confirmed by him over a period of years, that the extent of autokinesis seen by patients under test conditions is predictably related to the nature of the patient's illness. Some individuals, when placed in a totally darkened room for ten minutes and asked to look steadily at a stationary pinpoint of light,*will see that light move, while others consistently report no movement at all. A. C. Voth found that state hospital patients who carried diagnoses of alcoholism, hysteria, involutional melancholia, manic-depressive psychosis, paranoid conditions, and psychopathic personality, in the main reported little or no movement of the light in the autokinetic test. Patients with a diagnosis of schizophrenia, obsessional neurosis, or anxiety neurosis reported fairly extensive movement. In his work with normal subjects, A. C. Voth21showed that the autokinetic phenomenon