The bidirectional finding (that the same fictitious treatment can both relieve and aggravate symptoms in different patients) is the first documented nocebo observation in the modern medical literature and is the less-cited of the two findings reported in Haygarth’s 1800 Of the Imagination as a Cause and as a Cure of Disorders of the Body. The relief finding (the ‘cure’ direction) became the standard placebo-effect citation and is the basis of the famous Haygarth quotation; the worsening finding (the nocebo direction) was reported by Haygarth as a small number of cases at the Bath General Hospital trial of January 1799 and was not picked up by the medical literature until the 20th-century placebo-effect researchers re-discovered it. The claim is verification-status replicated because the bidirectional response has been re-reproduced under modern controlled conditions in 20th- and 21st-century clinical-trial methodology and is the established basis of the modern distinction between placebo and nocebo effects. The historiographic point Wootton emphasizes (Haygarth’s name ‘does not appear in histories of medicine for his discovery of either iatrogenesis or the placebo effect’, p.169) applies with even greater force to the nocebo observation, which is in effect rediscovered every generation.”