560. Let us pause here to consider the point which we have already reached. We began by defining hypnotism as the empirical development of the sleeping phase of man's personality. In that sleeping phase the most conspicuous element, - the most obvious function of the subliminal self, - is the repair of wasted tissues, the physical, and therefore also largely the moral, refreshment and rejuvenation of the tired organism. We have now traced the manner in which that function has been performed in the hypnotic state, and by suggestion and self-suggestion. We have found that the promised development of sleep is a reality; that we have in hypnotism a veritable evolution of those recuperative energies which give its practical value to sleep. From this side, - and it is from this side only that the mass of men regard sleep, - the case for hypnotism is now fairly complete; and this long chapter might here draw to a close.

The reader, however, knows that my initial promise would not in reality be thus fulfilled. My own definition of sleep, - of the phase of personality which I undertook that hypnotism would be found to develop, was of much wider scope. I believe that during sleep the subliminal self has other functions beyond the recuperation of the organism. Those other functions are concerned in some unknown way with the spiritual world; and the indication of their exercise is given by the sporadic occurrence, in the sleeping phase, of supernormal phenomena. Such phenomena, as we shall presently see, occur also at various points in hypnotic practice. To them we must now turn, if our account of the phenomena of induced somnambulism is to be complete.

561. Yet here, in order to give completeness to our intended review, we shall need a certain apparent extension of the scope of this chapter. We shall need to consider a group of cases which might have been introduced at various points in our scheme, but which are perhaps richest in their illustrations of the supernormal phenomena of hypnotism.

Spontaneous somnambulisms, - those crude uprushes of incoherent subliminal faculty which sometimes break through the surface of sleep, - seem to occupy a kind of midway position among the various phenomena through which our inquiry has thus far carried us.

The somnambulism often starts as an exaggerated dream; it develops into a kind of secondary personality. The thoughts and impulses which the upheaval raises into manifestation, - the psychical output, - resemble sometimes the inspirations of genius, sometimes the follies of hysteria. And, finally, the spontaneous sleep-waking state itself is manifestly akin to hypnosis, - is sometimes actually interchangeable with the induced somnambulisms of the hypnotic trance. The chain of memory which repeated spontaneous somnambulisms gradually form, - while lying quite outside the primary or waking memory, - will often be found to form part of the hypnotic memory, which gradually accretes in similar fashion from repeated hypnosis.

It would be easy to go further, and to compare these sudden uprushes of the subliminal during sleep to those urgent uprushes in waking hours which we shall presently have to discuss as sensory and motor automatisms. But the reader will already have understood the true affinities of these singular intercalations in the uniformity of sleep; - will already have realised that such things needs must be; - that it would have been strange indeed if that phase of the personality in which subliminal operation is relatively the most dominant should have been without those insurgences or outbreaks of the subliminal which even the most strenuous waking vigilance cannot always avert or control.

562. Nor, again, will it surprise us to find these sleep-wakings fertile in supernormal operation, though it be supernormal operation scattered and diffused upon random and trivial ends. What is here thrown forth comes not from the mine, but from the volcano; we have not to deal with therapeutic results educed by careful suggestion, but with the miscellaneous ejects of some focus of submerged excitation. From what has been observed in spontaneous somnambulism (I have already said), we might have divined almost the full range of phenomena to which induced somnambulism has now introduced us. Nay, even at the present day, the lessons of spontaneous somnambulism are not exhausted. They should teach us still to watch for further developments; they should forbid us to abandon, in the plain uniformity of hypnotic practice, our hope of some sudden felicitous inroad upon the more secret faculties of man.

563. For one form of sleep-waking capacity we are already prepared by what has been said in Chapter IV (Sleep). of the solution of problems in sleep. This is one of the ways in which we can watch the gradual merging of a vivid dream into a definite somnambulic act. The solution of a problem (as we have seen) may present itself merely as a sentence or a diagram, constructed in dream and remembered on waking. Or the sleeper (as in various cases familiar in text-books) may rise from bed and write out the chain of reasoning, or the sermon, or whatever it may be. Or again, in rarer cases ("Rachel Baker" is a curious example - see 563 A) the somnambulic output may take the form of oratory, and edifying discourses may be delivered by a preacher whom no amount of shaking or pinching will silence or, generally, even interrupt. This, so to speak, is genius with a vengeance; this is a too persistent uprush of subliminal zeal, co-operating even out of season with the hortatory instincts of the waking self.