We cannot dwell too long on the Demonomania of the Middle Ages, to which we have, perhaps, added some historical facts which are new and which we believe it to be our duty to publish, seeing a connection with modern hypnotism. We shall thus open a new field for investigation on strange affections, classed up to the present time in all varieties of monomania, but which appear to us to belong to a variety of mental pathology independent of insanity, properly speaking. If it were otherwise it would be necessary to recognize as crazy persons, not only the Demonomaniacs of the Middle Ages, but also the Jansenists, who went into trances, and the choreics and convulsionists (_convulsionnaires_) of the eighteenth century. They were certainly not crazy, those who came to the mortuary of Saint Medard, to the tomb of the Deacon Paris, to make an appeal against the Papal bull of Clement XI. And was it not another cause than auto suggestion, to which it is necessary to attribute the nervous phenomena that the _appelants_ exhibited during thirty consecutive years? The exaltation of religious ideas, so often advanced by psychologists, cannot account for these phenomena. I have seen palpable proofs of this in the various accidents that suddenly overcame sceptics and strong-minded men of modern times, who came as amateurs to assist at the experiments on convulsive subjects. These symptoms, as is well known, are usually ushered in by violent screams, rapid beatings of the heart, contractions of muscles, and analogous nervous symptoms. Besides, it is incontestible that many patients and infirm people obtain an unhoped for cure following convulsive cries; while others, in a state of health, are taken with hallucinations and delirium. I have seen patients who would lacerate certain portions of the body that were the seat of burns, and continue to walk, cry, gesticulate, and abuse themselves, like insane persons in a real state of dementia. The Jansenists did not speak, had no compacts with demons, no exorcisms at which Inquisitors and their acolytes could suggest ideas of demonomania; and notwithstanding their great austerities and the most rigorous fasts, we note among the _convulsionnaires_ of Saint Medard only the ideas of possession by the Holy Spirit and divine favors obtained through the protection of the kind-hearted Deacon; and meantime, those possessed by God, as by the Devil, were subjects of somnambulism, to trances, lethargy, catalepsy, and other phenomena.[80] The last analogy, finally, between the two nervous epidemics, was the Royal authority, a special form of _suggestion_ in the Middle Ages, which put an end to sorcery or witchcraft as well as to Jansenism. HYSTERIA AND PSYCHIC FORCE.