“Dr. Edward C. Spitzka, of New York, the noted alienist, has recently given several really remarkable instances of the power of mental suggestion. ‘In the graver forms of hysteria,’ says Dr. Spitzka, ‘when loss of sensation occurs in exactly one-half the body, you can lay a piece of tinted paper on the sensitive side; then suggesting it to be a mustard plaster, a red area will appear on the corresponding unsensitive side.’ Such blisters have produced permanent scars in similar cases. It is quite possible that the extent to which this mental suggestion may be advantageously employed is not fully appreciated by the medical profession.”

Scientific American, June 1899

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