They clearly establish one rule of medical practice which has always appeared to me highly important. In the best manner possible a patient ought to be always inspired with confidence in any remedy which is administered. Haygarth writes long before Charcot and the establishment of suggestion as legitimate therapy, but begins his monograph with an awareness of late eighteenth century literary theories of the imagination by Addison and Akenside. The Danish doctors, particularly Abildgaard, had noticed the necessity of belief on the part of the patient, but had not thought it integral to Perkinismen . But the cures increased elsewhere.
Genuine enthusiasm is wonderfully infectious.
Haygarth inadvertently touched upon an essential element of the placebo effect and alternative medicine and so did Gillray. The Tractors, reports Oliver Wendell Holmes in 1842, were almost forgotten by 1811. To come full circle, the advocates of Animal Magnetism did not forget Perkins. He assumes, of course, this agent to be magnetism, but it has to be something. Seen from a prescientific, almost magical view, the Tractors were visible translators of the invisible world, at that time seen to be one of galvanic electricity.