healthy; for they are all referable either to excess or deficiency of normal modes of mental action. That which is common to every form of insanity, which is frequently its first manifestation, and which, in so far as it exists, renders the lunatic irresponsible for his actions, is deficiency of volitional control over the current of thought and feeling, and consequently a want of self-direction and self-restraining power over the conduct. With this there may be a general disturbance either of intellectual or of emotional activity, or of both combined, constituting mania; or there may be a partial or limited disorder arising from excess or deficiency of some particular tendency constituting monomania.'1

ANESTHESIA.

§ 35. In passing into and emerging from the state of suspended consciousness produced by anæsthetics, there occur states of abnormal consciousness which are very like those described under the head of intoxication. The resemblance is rather more close to opium, or hasheesh, than to alcoholic influences. I will not detain the reader with details of these phenomena, as they present nothing different from facts already considered. A very interesting account of conscious experiences under chloroform is given in an Appendix to Vol. I. of Mr. Spencer's 'Principles of Psychology,' and quoted in Mind, No. XII.

DOUBLE CONSCIOUSNESS.

2

§ 36. In treating of somnambulism, I alluded (§ 15) to the fact that on a relapse into the dream state the sleeper would sometimes have a recollection of what happened in his consciousness during former somnambulistic states, though when awake he would have no memory of the same. This indicates the beginning of a very curious phase of mental development, which in a few abnormal instances has resulted in a double consciousness. I will quote from Professor Ribot a summary of the facts of three conspicuous cases: The most clearly defined and the most complete instance of periodic amnesia on record is the case of a young American woman, reported by Macnish in his "Philosophy of Sleep." It has often been quoted:-" Her memory was capacious and well stored with a copious stock of ideas. Unexpectedly, and without any forewarning, she fell into a profound sleep, which Mental Physiology, Chap. XVIII.

2 Diseases of Memory, Int. Sci. Series, p. 98 ff.

On waking

continued several hours beyond the ordinary term. she was discovered to have lost every trace of acquired knowledge. Her memory was tabula rasa-all vestiges both of words and things were obliterated and gone. It was found necessary for her to learn everything again. She even acquired by new efforts the art of spelling, reading, writing, and calculating, and gradually became acquainted with the persons and objects around like a being for the first time brought into the world. In these exercises she made considerable proficiency. But, after a few months, another fit of somnolency invaded her. On rousing from it she found herself restored to the state she was in before the first paroxysm; but was wholly ignorant of every event and occurrence that had befallen her afterward. The former condition of her existence she now calls the old state and the latter the new state; and she is as unconscious of her double character as two distinct persons are of their respective natures. For example, in her old state she possesses all the original knowledge, in her new state only what she acquired since. . . . In the old state she possesses fine powers of penmanship, while in the new she writes a poor awkward hand, having not had time or means to become an expert.' These periodical transitions lasted for four years.'

'Setting aside for the moment all that concerns the alternation of two personalities, it should be noted that there were found here two memories, each complete and absolutely independent of the other. Not only was the memory of personal impressions, the memory of consciousness, entirely and hopelessly dissevered, but also the semi-organic, semi-conscious memory by which we are able to speak, to read, and to write. The record does not tell us whether or no this description of memory extended to its purely organic forms-to habits (whether, for instance, the patient was obliged to learn anew the use of the hands in eating, dressing, etc.). But even supposing that this group of acquisitions remained intact, the separation into two distinct and independent groups is still as complete as the most exacting observer could desire.'

§ 37. A second, less complete but more common form of periodic amnesia is that of which Dr. Azam gives an interesting description in the case of Felida X., and of which Dr. Dufay found a parallel in one of his own patients. A woman of hysterical temperament was attacked in 1856 with a singular malady affecting her in such a manner that she lived a double. life, passing alternately from one to the other of two states, which

Dr. Azam defines as "the first condition" and "the second condition." In the normal or first condition, the woman was serious, grave, reserved, and laborious. Suddenly overcome with sleep, she would lose consciousness and awake in the second condition. In this state her character was changed; she became gay, imaginative, vivacious, and coquettish. She remembered perfectly all that had taken place in other similar states and during her normal life. Then, after the lapse of a longer or shorter period, she was again seized with a trance. On awaking she was in the first condition. But in this state she had no recollection of what had occurred in the second condition; she remembered only anterior normal periods. With increasing years the normal state (first condition) lasted for shorter and shorter and less frequent periods, while the transition from one state to the other, which had formerly occupied something like ten minutes, took place almost instantaneously.'

For purposes of

Such are the essential facts in this case. special study, it may be summed up in a few words. The patient passed alternately through two states; in one she possessed her memory entire; in the other she had only a partial memory, formed of all the impressions received in that state.'

'The case reported by Dr. Dufay is analogous to that just given. During the period corresponding with the second condition of Felida X., the patient was able to recall the minutest incidents which had taken place in the normal state, or during the period of somnambulism. There was also a change in character, and during the period of complete memory the patient designated the normal condition as d'état bête--the "brute state."

'It is worth noting that in this form of periodic amnesia, there is a part of the memory which is never wiped out, but which remains common to both conditions. "In these two states," Dr. Azam tell us," the patient was perfectly able to read, write, count, cut, and sew." There was not here, as in the case recorded by Macnish, complete disruption. The semi-conscious forms of memory co-operated equally with both phases of mental activity."

§ 38. On examining the general characteristics of periodic amnesia, as illustrated in the cases given, we find first an evolution of two memories. In extreme cases (Macnish) the two memories are independent of one another; when one appears, the other disappears. Each is self-supporting; each utilises, so to speak, its

For fuller accounts see Mind No. I., 414-553.

own material. The organised memory employed in speaking, reading, and writing is not a common basis of the two states. In each there is a distinct recollection of words, graphic signs, and the movements necessary to record them. In modified cases (Azam, Dufay, somnambulism) a partial memory alternates with the normal memory. The latter embraces the totality of conscious states; the former a limited group of states which, by a natural process of selection, separate from the others and form in the life of the individual a series of connected fragments. But they retain a common basis in the less stable and less conscious forms of. memory which enter indifferently into either group.'1

CONCLUDING REMARKS.

§ 39. After examining some of the leading varieties of abnormal consciousness, we are in the first place impressed with the truth of the general conclusion, that nowhere in such states do we see at work any different powers from those we see in exercise under normal conditions. A further examination fails to disclose any new laws of the operation of conscious activities. What we do find in all cases is either an exaltation or a deficiency of action in some normal mode. And abnormal conditions of some portion of the nervous system correspond exactly with and are always a key to the various sorts of abnormal consciousness. But wherever there is consciousness at all it exists according to the laws of redintegration and efferent activity, has its three aspects of feeling, cognition, and volition, and exhibits the elements which our general analysis brought out. Afferent influences, or some of them, may be cut off in one case, efferent activities may be interfered with in another, feeling may be exalted or depressed, cognitive movements may be arrested or quickened, but there is always a course of differentiation and integration according to the general laws we have laid down.

§ 40. We are also confirmed in our adhesion to the doctrine that the development of mind in the individual proceeds in correspondence with the development of life. For the result of conscious movements is the organisation of experiences so as generally to conform the individual to his environment, to effect the most perfect adjustment of inner to outer relations. Therefore, when there is any interference with the normal order of working of the mind's faculties, this adjustment is disturbed and the development Ribot op. cit.

of life is also interfered with. In those abnormal states which are of a temporary character, no harm may be done; but in the proportion that they become permanent, they tend to the destruction of the organism. Abnormal consciousness is hence disease, and, unless the normal order is restored, the effect upon life is disastrous.

§ 41. While this is generally true, it also appears that consciousness can exist, temporarily at any rate, in such an independence of normal conditions as to raise many questions as to its ultimate capacities of existence. Sensation may be blunted as in dreams, and yet the consciousness may be very active in representation. On the other hand in the hypnotic condition, and in some states of intoxication, there is a tremendous exaltation of the sensibilities. Whether there ever can be developed any normal conditions of these high powers of the senses and of the redintegrating activities is a query of great interest in its bearings on the future of the human race. Again, under extreme morbid conditions there appear those extraordinary exhibitions of intelligence and of feeling, which make us prone to believe that the existence of our conscious selves is not bound up with the integrity of our bodily organism. Indeed, when we consider the cases of double consciousness, the wonder comes over us whether even our birth may not be but a sleep and a forgetting.' As we move into this region of abnormal consciousness, the darkness of the unknown or the unknowable very speedily shuts in around us, with only here and there a star to guide us on our way.

6

CHAPTER XLVIII.

DEVELOPMENT IN THE LOWER ANIMALS.

§ 1. THE laws of development contained in the first chapter of this Part are generalisations from all the facts of consciousness wherever found. The different phases of development which form the subject-matter of the subsequent chapters have been set forth from examination of the facts of consciousness in general, and not any one individual's consciousness or the consciousness of any class or species of animate life. It is true what has been said has related more especially to human consciousness as of paramount interest in psychology, since it exhibits the highest developments