Thirteen days: Joseph Delboeuf versus Pierre Janet on the nature of hypnotic suggestion

American Journal of Clinical Hypnosis, Jul 2004 by Hammond, D Corydon

LeBlanc, A. (2004). Thirteen days: Joseph Delboeuf versus Pierre Janet on the nature of hypnotic suggestion. Journal of History & Behavioral Science, 40(2), 123-147. The article indicates that ideas about posthypnotic suggestion were introduced in 1884 wherein a subject was given a suggestion to return in 13 days and alerted with an amnesia.

How then does the subject count 13 days without knowing it? In 1886, Pierre Janet proposed the concept of dissociation as the reason, arguing that a second consciousness kept track of time outside of the subject's main consciousness. In 1885, Joseph Delboeuf, and in 1886, Hippolyte Bernheim proposed an alternative solution, arguing that subjects occasionally drifted into a hypnotic state in which they were reminded of the suggestion. This article traces the development of these competing theories and describes some of Delboeuf's final reflections on the problem of simulation and the nature of hypnosis. No address available for reprints.