The brief review already made will suffice to indicate the complex and separable nature of the elements of human personality. Of course a far fuller list might have been given; many phenomena of actual insanity would need to be cited in any complete conspectus. But hysteria is in some ways a better dissecting agent than any other where delicate psychical dissociations are concerned. Just as the microscopist stains a particular tissue for observation, so does hysteria stain with definiteness, as it were, particular synergies—definite complexes of thought and action—more manifestly than any grosser lesion, any more profound or persistent injury could do. Hysterical mutism, for instance (the observation is Charcot's[27]), supplies almost the only cases where the faculty of vocal utterance is attacked in a quite isolated way. In aphasia dependent upon organic injury we generally find other word-memories attacked also,—elements of agraphy, of word-blindness, of word-deafness appear. In the hysteric the incapacity to speak may be the single symptom. So with anæsthesiæ; we find in hysteria a separation of sensibility to heat and to pain, possibly even a separate subsistence of electrical sensibility. It is worth remarking here that it was during the hypnotic trance, which in delicacy of discriminating power resembles hysteria, that (so far as I can make out) the distinctness of the temperature-sense from the pain-sense was first observed. Esdaile, when removing tumours under mesmerism in Calcutta, noticed that patients, who were actually undergoing capital operations without a murmur, complained if a draught blew in upon them from an open window.
Nor is it only as a dissecting agent that hysteria can aid our research. There are in hysteria frequent acquisitions as well as losses of faculty. It is not unusual to find great hyperæsthesia in certain special directions—of touch, hearing, perception of light, etc.—combined with hysterical loss of sensation of other kinds. This subject will be more conveniently treated along with the hyperæsthesia of the hypnotic trance. But I may note here that just such occasional quickenings of faculty were, in my view, almost certain to accompany that instability of psychical threshold which is the distinguishing characteristic of hysteria, since I hold that subliminal faculty habitually overpasses supraliminal. These also are a kind of capricious idées fixes; only the caprice in such cases raises what was previously submerged instead of exaggerating what was previously emergent.
And from this point it is that our inquiries must now take their fresh departure. We in this work are concerned with changes which are the converse of hysterical changes. We are looking for integrations in lieu of disintegrations; for intensifications of control, widenings of faculty, instead of relaxation, scattering, or decay.
Suppose, then, that in a case of instability of the psychical threshold,—ready permeability, if you will, of the psychical diaphragm separating the supraliminal from the subliminal self,—the elements of emergence tend to increase and the elements of submergence to diminish. Suppose that the permeability depends upon the force of the uprushes from below the diaphragm rather than on the tendency to sink downwards from above it. We shall then reach the point where the vague name of hysteria must give place to the vague name of genius. The uprushes from the subliminal self will now be the important feature; the down-draught from the supraliminal, if it still exists, will be trivial in comparison. The content of the uprush will be congruous with the train of voluntary thought; and the man of genius will be a man more capable than others of utilising for his waking purposes the subliminal region of his being.
Next in order to the uprushes of genius will come the uprushes of dream. All men pass normally and healthily into a second phase of personality, alternating with the first. That is sleep, and sleep is characterised by those incoherent forms of subliminal uprush which we know as dreams. It is here that our evidence for telepathy and telæsthesia will first present itself for discussion. Sleep will indicate the existence of submerged faculty of a rarer type than even that to which genius has already testified.
There are, moreover, other states, both spontaneous and induced, analogous to sleep, and these will form the subject of the fifth chapter, that on Hypnotism. Hypnotism, however, does not mean trance or somnambulism only. It is a name, if not for the whole ensemble, yet for a large group of those artifices which we have as yet discovered for the purpose of eliciting and utilising subliminal faculty. The results of hypnotic suggestion will be found to imitate sometimes the subliminal uprushes of genius, and sometimes the visions of spontaneous somnambulism; while they also open to us fresh and characteristic accesses into subliminal knowledge and power.
Further than this point our immediate forecast need not go. But when we have completed the survey here indicated, we shall see, I think, how significant are the phenomena of hysteria in any psychological scheme which aims at including the hidden powers of man. For much as the hysteric stands in comparison to us ordinary men, so perhaps do we ordinary men stand in comparison with a not impossible ideal of faculty and of self-control.
But apart from these broader speculations, it has become evident that disturbances of personality are not mere empty marvels, but psycho-pathological problems of the utmost interest:—no one of them exactly like another, and no one of them without some possible aperçu into the intimate structure of man.
The purpose of this book, of course, is not primarily practical. It aims rather at the satisfaction of scientific curiosity as to man's psychical structure; esteeming that as a form of experimental research which the more urgent needs of therapeutics have kept in the background too long. Yet it may not have been amiss to realise thus, on the threshold of our discussion, that already even the most delicate speculations in this line have found their justification in helpful act; that strange bewilderments, paralysing perturbations, which no treatment could alleviate, no drug control, have been soothed and stablished into sanity by some appropriate and sagacious mode of appeal to a natura medicatrix deep-hidden in the labouring breast.