Suggestion: Nancy’s working idea
Suggestion is the Nancy school’s name for the idea that communicated expectations can change experience and movement. It is a methods concept, not a treatment grade.
Last reviewed 27 August 2026
Suggestion, in the Nancy sense, is a communicated idea that the subject realises as experience, movement, or later action. It is not Mesmer’s fluid and not a brand of “positive thinking.”
Key evidence
Bernheim’s Suggestive Therapeutics states that suggestion is “the key to Braidism” and “the key to all hypnotic phenomena.” He treats catalepsy, transfer, and contracture as psychical effects of suggestion, and denies that hypnotic sleep is a neurosis analogous to hysteria. The argument is set out on the Nancy school page.
The same book describes suggestion without sleep, and post-hypnotic suggestions to be realised after waking. Those are method observations from a nineteenth-century clinic.
Response expectancy is a later laboratory way of talking about what people expect to feel. It is not the same text as Bernheim, but it occupies the same non-fluid side of the argument.
Limitations
A key phrase in an 1880s treatise is not a modern dismantling trial. Clinic counts are not effect sizes.
What we don't know yet
Which fragments of “suggestion” (wording, rapport, expectancy, compliance) drive later trial outcomes is largely untested in the sources cited here.
This page is informational only.