The history of _incubi_, or "night-comers," is doubtless, to a large extent, a narrative of the hallucinations, delusions, and automatic thoughts of the insane, although to _what_ extent would be a difficult question to determine, because some were assuredly frightened into the confessions which they made; and, further, it is hard to say how much of a certain belief was due to the current popular ignorance and credulity, and how much to actual mental disease. Still the ignorant opinions of an age find their _nisus_ and most rapid development in persons of weak or diseased mind, and they form the particular delusion manifested; and at a period when witches are universally believed in, there must be some reason why one believes he or she has had transactions with Satan, and another does not believe it. It is, indeed, impossible to read the narratives of some of the unfortunate hags who were put to death for witchcraft, without recognizing the well-marked features of the victims of cerebral disorder. In this way I have no doubt a considerable number of mad people were destroyed. Their very appearance suggested to their neighbours the notion of something weird and impish; the physiognomy of madness was mistaken for that of witchcraft, while the poor wretches themselves, conscious of unaccustomed sensations and singular promptings, referred them to the agency of demons. Strangely enough, even an inquisitor--Nider, who died in 1440--gives many instances of persons whose symptoms he himself recognized as those not of possession, but of madness. It is hardly necessary to say that the treatment of the unfortunate lunatics and epileptics who were judged to be witches by James I. was nothing else than death, and he thus coolly comments on this punishment: "It is commonly used by fire, but that is an indifferent thing, to be used in every country, according to the law or custom thereof."[49]