And it is of this fascination that Avicenna and al-Gazali have spoken; S. Thomas too thus mentions this fascination, Part I, question 117. For he says the mind of a man may be changed by the influence of another mind. And that influence which is exerted over another often proceeds from the eyes, for in the eyes a certain subtle influence may be concentrated. For the eyes direct their glance upon a certain object without taking notice of other things, and although the vision be perfectly clear, yet at the sight of some impurity, such, for example, a woman during her monthly periods, the eyes will as it were contract a certain impurity. This is what Aristotle says in his work On Sleep and Waking,128 and thus if anybody’s spirit be inflamed with malice or rage, as is often the case with old women, then their disturbed spirit looks through their eyes, for their countenances are most evil and harmful, and often terrify young children of tender years, who are extremely impressionable. And it may be that this is often natural, permitted by God; on the other hand, it may be that these evil looks are often inspired by the malice of the devil, with whom old witches have made some secret contract.
The next question arises with regard to the influence of the heavenly bodies, and here we find three very common errors, but these will be answered as we proceed to the explain other matters.
With regard to operations of witchcraft, we find that some of these may be due to mental influence over others, and in some cases such mental influence might be a good one, but it is the motive which makes it evil.
And there are four principal arguments which are to be objected against those who deny that there are witches, or magical operations, which may be performed at the conjunction of certain planets and stars, and that by the malice of human beings harm may be wrought through fashioning images, through the use of spells, and by the writing of mysterious characters. All theologians and philosophers agree that the heavenly bodies are guided and directed by certain spiritual mediums. But those spirits are superior to our minds and souls, just as the heavenly bodies are superior to other bodies, and therefore they can influence both the mind and body of a man, so that he is persuaded and directed to perform some human act. But in order yet more fully to attempt a solution of these matters, we may consider certain difficulties from a discussion of which we shall yet more clearly arrive at the truth. First, spiritual substance cannot change bodies to some other natural form unless it be through the mediumship of some agent. Therefore, however strong a mental influence may be, it cannot effect any change in a man’s mind or disposition. Moreover, several universities, especially that of Paris, have condemned the following article:—That an enchanter is able to cast a camel into a deep ditch merely by directing his gaze upon it. And so this article is condemned, that a corporeal body should obey some spiritual substance if this be understood simply, that is to say, if the obedience entails some actual change or transformation. For in regard to this it is God alone Who is absolutely obeyed. Bearing these points in mind we may soon see how that fascination, or influence of the eyes of which we have spoken, is possible. For it is not possible that a man through the natural powers of his mind should direct such power from his eyes that, without the agency of his own body or of some other medium, he should be able to do harm to the body of another man. Nor is it possible that a man through the natural powers of his mind should at his will bring about some change, and by directing this power through the mediumship of his eyes entirely transform the body of a man, upon whom he fixes his gaze, just as his will and pleasure may be.
And therefore in neither of these ways can one man influence another and fascinate another, for no man by the natural powers of his mind alone possesses such an extraordinary influence. Therefore, to wish to prove that evil effects can be produced by some natural power is to say that this natural power is the power of the devil, which is very far indeed from the truth.
Nevertheless, we may more clearly set forth how it is possible for a careful gaze to do harm. It may so happen that if a man or a woman gaze steadfastly at some child, the child, owing to its power of sight and power of imagination, may receive some very sensible and direct impression. And an impression of this kind is often accompanied by a bodily change, and since the eyes are one of the tenderest organs of the body, therefore they are very liable to such impressions. Therefore it may well happen that the eyes receive some bad impression and change for the worse, since very often the thoughts of the mind or the motions of the body are particularly impressed upon and shown by the eyes. And so it may happen that some angry and evil
