The above points have been fair matter of argument almost since our research began. But as our evidence has developed, our conception of telepathy has needed to be more and more generalised in other and new directions,—still less compatible with the vibration theory. Three such directions may be briefly specified here—namely, the relation of telepathy (a) to telæsthesia or clairvoyance, (b) to time, and (c) to disembodied spirits. (a) It is increasingly hard to refer all the scenes of which percipients become aware to the action of any given mind which is perceiving those distant scenes. This is especially noticeable in crystal-gazing experiments. (b) And these crystal visions also show what, from the strict telepathic point of view, we should call a great laxity of time relations. The scryer chooses his own time to look in the ball;—and though sometimes he sees events which are taking place at the moment, he may also see past events,—and even, as it seems, future events. I at least cannot deny precognition, nor can I draw a definite line amid these complex visions which may separate precognition from telepathy (see Proceedings S.P.R., vol. xi. pp. 408-593). (c) Precognition itself may be explained, if you will, as telepathy from disembodied spirits;—and this would at any rate bring it under a class of phenomena which I think all students of our subject must before long admit. Admitting here, for argument's sake, that we do receive communications from the dead which we should term telepathic if we received them from the living, it is of course open to us to conjecture that these messages also are conveyed on ether-waves. But since those waves do not at any rate emanate from material brains, we shall by this time have got so far from the original brain-wave hypothesis that few will care still to defend it.
I doubt, indeed, whether we can safely say of telepathy anything more definite than this: Life has the power of manifesting itself to life. The laws of life, as we have thus far known them, have been only laws of life when already associated with matter. Thus limited, we have learnt little as to Life's true nature. We know not even whether Life be only a directive Force, or, on the other hand, an effective Energy. We know not in what way it operates on matter. We can in no way define the connection between our own consciousness and our organisms. Just here it is, I should say, that telepathic observations ought to supply us with some hint. From the mode in which some element of one individual life,—apart from material impact,—gets hold of another organism, we may in time learn something of the way in which our own life gets hold of our own organism,—and maintains, intermits, or abandons its organic sway.[108]
The hypothesis which I suggested in Phantasms of the Living itself, in my "Note on a possible mode of psychical interaction," seems to me to have been rendered increasingly plausible by evidence of many kinds since received; evidence of which the larger part falls outside the limits of this present work. I still believe—and more confidently than in 1886—that a "psychical invasion" does take place; that a "phantasmogenetic centre" is actually established in the percipient's surroundings; that some movement bearing some relation to space as we know it is actually accomplished; and some presence is transferred, and may or may not be discerned by the invaded person; some perception of the distant scene in itself is acquired, and may or may not be remembered by the invader.
But the words which I am here beginning to use carry with them associations from which the scientific reader may well shrink. Fully realising the offence which such expressions may give, I see no better line of excuse than simply to recount the way in which the gradual accretion of evidence has obliged me, for the mere sake of covering all the phenomena, to use phrases and assumptions which go far beyond those which Edmund Gurney and I employed in our first papers on this inquiry in 1883.
When in 1882 our small group began the collection of evidence bearing upon "veridical hallucinations"—or apparitions which coincided with other events in such a way as to suggest a causal connection—we found scattered among the cases from the first certain types which were with difficulty reducible under the conception of telepathy pure and simple—even if such a conception could be distinctly formed. Sometimes the apparition was seen by more than one percipient at once—a result which we could hardly have expected if all that had passed were the transference of an impression from the agent's mind to another mind, which then bodied forth that impression in externalised shape according to laws of its own structure. There were instances, too, where the percipient seemed to be the agent also—in so far that it was he who had an impression of having somehow visited and noted a distant scene, whose occupant was not necessarily conscious of any immediate relation with him. Or sometimes this "telepathic clairvoyance" developed into "reciprocity," and each of the two persons concerned was conscious of the other;—the scene of their encounter being the same in the vision of each, or at least the experience being in some way common to both. These and cognate difficulties were present to my mind from the first; and in the above-mentioned "Note on a suggested mode of psychical interaction," included in vol. ii of Phantasms of the Living, I indicated briefly the extension of the telepathic theory to which they seemed to me to point.
Meantime cases of certain other definite types continued to come steadily to hand, although in lesser numbers than the cases of apparition at death. To mention two important types only—there were apparitions of the so-called dead, and there were cases of precognition. With regard to each of these classes, it seemed reasonable to defer belief until time should have shown whether the influx of first-hand cases was likely to be permanent; whether independent witnesses continued to testify to incidents which could be better explained on these hypotheses than on any other. Before Edmund Gurney's death in 1888 our cases of apparitions and other manifestations of the dead had reached a degree of weight and consistency which, as his last paper showed, was beginning to convince him of their veridical character; and since that date these have been much further increased; and especially have drawn from Mrs. Piper's and other trance-phenomena an unexpected enlargement and corroboration. The evidence for communication from the departed is now in my personal estimate quite as strong as that for telepathic communication between the living; and it is moreover evidence which inevitably alters and widens our conception of telepathy between living men.
The evidence for precognition, again, was from the first scantier, and has advanced at a slower rate. It has increased steadily enough to lead me to feel confident that it will have to be seriously reckoned with; but I cannot yet say—as I do say with reference to the evidence for messages from the departed—that almost every one who accepts our evidence for telepathy at all, must ultimately accept this evidence also. It must run on at any rate for some years longer before it shall have accreted a convincing weight.
But at whatever point one or another inquirer may happen at present to stand, I urge that this is the reasonable course for conviction to follow. First analyse the miscellaneous stream of evidence into definite types; then observe the frequency with which these types recur, and let your sense of their importance gradually grow, if the evidence grows also.
Now this mode of procedure evidently excludes all definite a priori views, and compels one's conceptions to be little more than the mere grouping to which the facts thus far known have to be subjected in order that they may be realised in their ensemble.
"What definite reason do I know why this should not be true?"—this is the question which needs to be pushed home again and again if one is to realise—and not in the ordinary paths of scientific speculation alone—how profound our ignorance of the Universe really is.