We shall thus have two phases of personality developing into separate purposes and in separate directions from a parent stem. The waking personality will develop external sense organs and will fit itself progressively for the life of relation to the external world. It will endeavour to attain an ever completer control over the resources of the personality, and it will culminate in what we term _genius_ when it has unified the subliminal as far as possible with the supraliminal in its pursuit of deliberate waking ends. The sleeping personality will develop in ways less easy to foresee. What, on any theory, will it aim at, beyond the familiar intensification of recuperative power? We can only guess, on my theory, that its development will show some increasing trace of the soul's less exclusive absorption in the activity of the organism. The soul has withdrawn from the specialised material surface of things (to use such poor metaphor as we can) into a realm where the nature of the connection between matter and spirit--whether through the intermediacy of the ether or otherwise--is more profoundly discerned. That same withdrawal from the surface which, while it diminishes power over complex muscular processes, increases power over profound organic processes, may at the same time increase the soul's power of operating in that spiritual world to which sleep has drawn it nearer. On this view of sleep, be it observed, there will be nothing to surprise us in the possibility of increasing the proportion of the sleeping to the waking phase of life by hypnotic suggestion. All we can say is that, while the soul must insist on at least the minimum quantity of sleep needful to keep the body alive, we can see no superior limit to the quantity of sleep which it may choose to take,--the quantity of attention, that is, which it may choose to give to the special operations of sleep as compared with those of waking life. At this point we must for the present pause. The suggested hypothesis will indeed cover the actual facts as to sleep adduced in this chapter. But it covers them by virtue of assumptions too vast to be accepted without further confirmation. It must necessarily be our duty in later chapters to trace the development of the sleeping personality in both the directions indicated above;--in the direction of organic recuperation through the hypnotic trance, and in the direction of the soul's independent operation through that form of trance which leads to possession and to ecstasy. We shall begin at once in the next chapter to trace out that great experimental modification of sleep, from which, under the names of mesmerism or of hypnotism, results of such conspicuous practical value have already been won. CHAPTER V HYPNOTISM εἱλετο ἑ ῥἁβδον, τὑ τ' ἁνδρὡν δμματα θελγει, ὁν ἑθἑλει, τοὑς δ' αὑτε κἱ ὑπνὡοτας ἑγεἱρι. --HOMER.