Though frequently Manichaean in practice, Christianity was never Manichaean in its dogmas. In this respect it differs from our modern idolatries of Communism and Nationalism, which are Manichaean not only in action, but also in creed and theory. Today it is everywhere self-evident that we are on the side of Light, they on the side of Darkness. And being on the side of Darkness, they deserve to be punished and must be liquidated (since our divinity justifies everything) by the most fiendish means at our disposal. By idolatrously worshipping ourselves as Ormuzd, and by regarding the other fellow as Ahriman, the Principle of Evil, we of the twentieth century are doing our best to guarantee the triumph of diabolism in our time. And on a very small stage, this precisely was what the exorcists were doing at Loudun. By idolatrously identifying God with the political interests of their sect, by concentrating their thoughts and their efforts on the powers of evil, they were doing their best to guarantee the triumph (local, fortunately, and temporary) of that Satan against whom they were supposed to be fighting.

For our present purposes it is unnecessary either to affirm or deny the existence of non-human intelligences capable of possessing the bodies of men and women. The only question we have to ask ourselves is this: granted the existence of such intelligences, is there any reason to believe that they were responsible for what happened to the Ursulines of Loudun? Modern Catholic historians are unanimously agreed that Grandier was innocent of the crime for which he was tried and condemned; but some of them—they are cited by the Abbé Brémond in his Histoire Littéraire du Sentiment Religieux en France—are still convinced that the nuns were the victims of a genuine possession. How such and opinion can be held by anyone who has read the relevant documents, and who has even the slightest knowledge of abnormal psychology, I confess myself unable to understand. There is nothing in the behaviour of the nuns which cannot be paralleled in the many cases of hysteria recorded, and successfully treated, by modern psychiatrists. And there is no evidence that any of the nuns ever manifested any of the paranormal powers which, according to the doctrines of the Roman Church, are the hall-marks of a genuine diabolic invasion.

How is true possession to be distinguished from fraud or the symptoms of disease? The Church prescribes four tests—the language test, the test of preternatural physical strength, the test of levitation and the test of clairvoyance and prevision. If a person can on occasion understand, or better still, speak a language of which, in his normal state, he is completely ignorant; if he can manifest the physical miracle of levitation or perform unaccountable feats of strength; and if he can correctly predict the future or describe events taking place at a distance—then that person may be presumed to be possessed by devils. (Alternatively, he may be presumed to be the recipient of extraordinary graces; for in many instances divine and infernal miracles are, most unhappily, identical. The levitation of saintly ecstatics is distinguishable from the levitation of ecstatic demoniacs only in virtue of the moral antecedents and consequences of the event. These moral antecedents and consequences are often hard to assess, and it has sometimes happened that even the holiest persons have been suspected of producing their ESP phenomena and their PK effects1 by diabolic means.)

Such are the official and time-hallowed criteria of diabolic possession. For us, these ESP and PK phenomena prove only that the old notion of a completely watertight soul is untenable. Below and beyond the conscious self lie vast ranges of subconscious activity, some worse than the ego and some better, some stupider and some, in certain respects, far more intelligent. At its fringes this subconscious self overlaps and merges with not-self, with the psychic medium in which all selves bathe and through which they can directly communicate with one another and with cosmic Mind. And somewhere on these subconscious levels individual minds make contact with energy, and make contact with it not merely in their own body, but also (if the anecdotic and statistical evidence may be trusted) outside their own body. The older psychology, as we have seen, was compelled by its own dogmatic definitions to ignore subconscious mental activity; in order to account for the observed facts, it had to postulate the devil.

For the moment, let us place ourselves in the intellectual position of the exorcists and their contemporaries. Accepting as valid the Church’s criteria of possession, let us examine the evidence on which the nuns were pronounced to be demoniacs and the parson a sorcerer. We will begin with the test which, because it was the easiest of application, was in practice the most frequently applied—the test of language.

For all the Christians of an earlier day, “speaking with tongues” was an extraordinary grace, a gratuitous gift of the Holy Spirit. But it was also (such is the strangely equivocal nature of the universe) a sure symptom of possession by devils. In the great majority of cases, glossolalia is not a clear and unmistakable speaking of some hitherto unknown tongue. It is a more or less articulate, more or less systematic gibberish, exhibiting certain resemblances to some form of traditional speech and consequently interpretable, by listeners of good-will, as a rather obscure utterance in some language with which they happen to be familiar. In the cases where persons in a state of trance have shown an unequivocal knowledge of some language of which they were consciously ignorant, investigation has generally revealed the fact that they had spoken the language during childhood and subsequently forgotten it, or that they had heard it spoken and, without understanding the meaning of the words, had unconsciously familiarized themselves with their sound. For the rest there is, in the words of F. W. H. Myers, “little evidence of the acquisition—telepathy apart—of any actual mass of fresh knowledge, such as a new language, or a stage of mathematical knowledge unreached before.” In the light of what we know, through systematic psychical research, of trance mediumship and automatic writing, it seems questionable whether any alleged demoniac ever passed the test of language in a completely unambiguous and decided manner. What is certain is that the recorded cases of complete failure are very numerous, while the recorded successes are mostly partial and rather unconvincing. Some of the ecclesiastical investigators of possession applied the language test in very ingenious and effective ways. In 1598, for example, Marthe Brossier made a great name for herself by exhibiting the symptoms of possession. One of these symptoms—a thoroughly traditional and orthodox symptom—consisted in going into convulsions every time a prayer or an exorcism was read over her. (Devils hate God and the Church; consequently they tend to fly into a rage every time they hear the hallowed words of the Bible or the prayer book.) To test Marthe’s paranormal knowledge of Latin, the Bishop of Orléans opened his Petronius and solemnly intoned the somewhat unedifying story of the Matron of Ephesus. The effect was magical. Before the first sonorous sentence had been completed, Marthe was rolling on the floor, cursing the Bishop for what he was making her suffer by his reading of the Sacred Word. It is worth remarking that, far from putting an end to Marthe’s career as a demoniac, this incident actually helped her to go forward to fresh triumphs. Fleeing from the Bishop, she put herself under the protection of the Capuchins, who proclaimed that she had been unjustly persecuted and made use of her to draw enormous crowds to their exorcisms.