This critical state, when the conscious mind is liable to be submerged at any moment in the unconscious, is akin to the "loss of soul" that frequently attacks primitives. It is a sudden abaissement du niveau menial, a slackening of the conscious tension, to which primitive man is especially prone because his consciousness is still relatively weak and means a considerable effort for him. Hence his lack of will-power, his inability to concentrate and the fact that, mentally, he tires so easily, as 1 have experienced to my cost during palavers. The widespread practice of yoga and dhyana in the East is a similar abaissement deliberately induced for the purpose of relaxation, a technique for releasing the soul. With certain patients, I have even been able to establish the existence of subjectively experienced levitations in moments of extreme derangement.3 Lying in bed, the patients felt that they were floating horizontally in the air a few feet above their bodies. This is a suggestive reminder of the phenomenon called the "witch's trance," and also of the parapsychic levitations reported of many saints.