But there are some points to be noted for the clearer understanding of what has already been written concerning this matter. First, it must in no way be believed that such members are really torn right away from the body, but that they are hidden by the devil through some prestidigitory art so that they can be neither seen nor felt. And this is proved by the authorities and by argument; although is has been treated of before, where Alexander of Hales says that a Prestige, properly understood, is an illusion of the devil, which is not caused by any material change, but exists only in the perceptions of him who is deluded, either in his interior or exterior senses.
With reference to these words it is to be noted that, in the case we are considering, two of the exterior senses, namely, those of sight and touch, are deluded, and not the interior senses, namely, common sense, fancy, imagination, thought, and memory. (But S. Thomas says they are only four, as has been told before, reckoning fancy and imagination as one; and with some reason, for there is little difference between imagining and fancying. See S. Thomas, I, 79.) And these senses, and not only the exterior senses, are affected when it is not a case of hiding something, but the causing something to appear to a man either when he is aware or asleep.
As when a man who is awake sees things otherwise than as they are; such as seeing someone devour a horse with its rider, or thinking he sees a man transformed into a beast, or thinking that he is himself a beast and must associate with beasts. For then the exterior senses are deluded and are employed by the interior senses. For by the power of devils, with God’s permission, mental images long retained in the treasury of such images, which is the memory, are drawn out, not from the intellectual understanding in which such images are stored, but from the memory, which is the repository of mental images, and is situated at the back of the head, and are presented to the imaginative faculty. And so strongly are they impressed on that faculty that a man has an inevitable impulse to imagine a horse or a beast, when the devil draws from the memory an image of a horse or a beast; and so he is compelled to think that he sees with his external eyes such a beast when there is actually no such beast to see; but it seems to be so by reason of the impulsive force of the devil working by means of those images.
And it need not seem wonderful that devils can do this, when even a natural defect is able to effect the same result, as is shown in the case of frantic and melancholy men, and in maniacs and some drunkards, who are unable to discern truly. For frantic men think they see marvellous things, such as beasts and other horrors, when in actual fact they see nothing. See above, in the question, Whether witches can turn the minds of men to love and hatred; where many thing are noted.
And, finally, the reason is self-evident. For since the devil has power over inferior things, except only the soul, therefore he is able to effect certain changes in those things, when God allows, so that things appear to be otherwise than they are. And this he does, as I have said, either by confusing and deluding the organ of sight so that a clear thing appears cloudy; just as after weeping, owing to the collected humours, the light appears different from what it was before. Or by operating on the imaginative faculty by a transmutation of mental images, as has been said. Or by some agitation of various humours, so that matters which are earthy and dry seem to be fire or water: as some people make everyone in the house strip themselves naked under the impression that they are swimming in water.
It may be asked further with reference to the above method of devils, whether this sort of illusions can happen indifferently to the good and to the wicked: just as other bodily infirmities can, as will be shown later, be brought by witches even upon those who are in a state of grace. To this question, following the words of Cassian in his Second Collation of the Abbot Sirenus, we must answer that they cannot. And from this it follows that all who are deluded in this way are presumed to be in deadly sin. For he says, as is clear from the words of S. Antony: The devil can in no way enter the mind or body of any man, nor has the power to penetrate into the thoughts of anybody, unless such a person has first become destitute of all holy thoughts, and is quite bereft and denuded of spiritual contemplation.
This agrees with Boethius where he says in the Consolation of Philosophy:176 We had given you such arms that, if you had not thrown them away, you would have been preserved from infirmity.
Also Cassian tells in the same place of two Pagan witches, each in his own way malicious, who by their witchcraft sent a succession of devils into the cell of S. Antony for the purpose of driving him from there by their temptations; being infected with hatred for the holy man because a great number
