We have thus three parallelisms which may guide and limit our expectations. From the parallelism of possession with split personalities we may infer that a possessing spirit is not likely to be able to inspire into the recipient brain ideas or words of very unfamiliar type. From the parallelism of possession with dream we may infer that the memory of the possessing spirit may be subject to strange omissions and confusions. From the parallelism with somnambulism we may infer that colloquy between a human observer and the possessing spirit is not likely to be full or free, but rather to be hampered by difference of state, and abbreviated by the difficulty of maintaining psychical contact for long together.

These remarks will, I hope, prepare the reader to consider the problems of possession with the same open-mindedness which has been needed for the study of previous problems attacked in the present work.

But before we can proceed to the actual evidence there is another aspect of possession which must be explained. A group of phenomena are involved which have in various ways done much to confuse and even to retard our main inquiry, but which, when properly placed and understood, are seen to form an inevitable part of any scheme which strives to discover the influence of unseen agencies in the world we know.

In our discussion of all telepathic and other supernormal influence I have thus far regarded it mainly from the psychological and not from the physical side. I have spoken as though the field of supernormal action has been always the metetherial world. Yet true as this dictum may be in its deepest sense, it cannot represent the whole truth "for beings such as we are, in a world like the present." For us every psychological fact has (so far as we know) a physical side; and metetherial events, to be perceptible to us, must somehow affect the world of matter.

In sensory and motor automatisms, then, we see effects, supernormally initiated, upon the world of matter.

Imprimis, of course, and in ordinary life our own spirits (their existence once granted) affect our own bodies and are our standing examples of spirit affecting matter. Next, if a man receives a telepathic impact from another incarnate spirit which causes him to see a phantasmal figure, that man's brain has, we may suppose, been directly affected by his own spirit rather than by the spirit of the distant friend. But it may not always be true even in the case of sensory automatisms that the distant spirit has made a suggestion merely to the percipient's spirit which the percipient's own spirit carries out; and in motor automatisms, as they develop into possession, there are indications, as I have already pointed out, that the influence of the agent's spirit is telergic rather than telepathic, and that we have extraneous spirits influencing the human brain or organism. That is to say, they are producing movements in matter;—even though that matter be organised matter and those movements molecular.

So soon as this fact is grasped,—and it has not always been grasped by those who have striven to establish a fundamental difference between spiritual influence on our spirits and spiritual influence on the material world,—we shall naturally be prompted to inquire whether inorganic matter as well as organic ever shows the agency of extraneous spirits upon it. The reply which first suggests itself is, of course, in the negative. We are constantly dealing with inorganic matter, and no hypothesis of spiritual influence exerted on such matter is needed to explain our experiments. But this is a rough general statement, hardly likely to cover phenomena so rare and fugitive as many of those with which in this inquiry we deal. Let us begin, so to say, at the other end; not with the broad experience of life, but with the delicate and exceptional cases of possession of which we have lately been speaking.

Suppose that a discarnate spirit, in temporary possession of a living organism, is impelling it to motor automatisms. Can we say a priori what the limits of such automatic movements of that organism are likely to be, in the same way as we can say what the limits of any of its voluntary movements are likely to be? May not this extraneous spirit get more motor power out of the organism than the waking man himself can get out of it? It would not surprise us, for example, if the movements in trance showed increased concentration; if a dynamometer (for instance) was more forcibly squeezed by the spirit acting through the man than by the man himself. Is there any other way in which one would imagine that a spirit possessing me could use my vital force more skilfully than I could use it myself?

I do not know how my will moves my arm; but I know by experience that my will generally moves only my arm and what my arm can touch;—whatever objects are actually in contact with the "protoplasmic skeleton" which represents the life of my organism. Yet I can sometimes move objects not in actual contact, as by melting them with the heat or (in the dry air of Colorado) kindling them with the electricity, which my fingers emit. I see no very definite limit to this power. I do not know all the forms of energy which my fingers might, under suitable training, emit.

And now suppose that a possessing spirit can use my organism more skilfully than I can. May he not manage to emit from that organism some energy which can visibly move ponderable objects not actually in contact with my flesh? That would be a phenomenon of possession not very unlike its other phenomena;—and it would be telekinesis.