1 "The Unconscious," The Macmillan Co., p. 197.

I mention this as only one illustration of the data which can be obtained from abnormal and experimental psychology, for the understanding of dream processes. I doubt if there is a single phenomenon observed in dreams, or peculiarity of the work of the dream mind, that is not also to be found in other conditions than sleep. I mean conditions, whether artificially produced or the abnormal resultant of intrinsic psychological processes, where the mind is dissociated as it is in sleep. By correlating dream phenomena with analogous phenomena found in these other conditions and studying the mechanisms and essential characteristics of the abnormal and artificial groups, particularly by the experimental method, we can obtain an insight into and understanding of the normal dream mind. The study of abnormal psychology - including its variant produced by artifice - has thrown more light on the workings of the normal mind than all the centuries of academic studies of the latter.

Mrs. Arnold-Forster directs attention to certain characteristics of memory and imagination in dreams (Chapter V). The former is remarkable for the wealth and distinctness of detail with which former scenes and experiences are reproduced; indeed, it may be, visualised with a vividness equal to reality. Even momentary experiences which originally were merely fugitive impressions, casually attended to, may reappear in wonderful detail and distinctness as the material of dreams.

This feat of memory is not peculiar to dreams, but may be correlated with the same phenomenon manifested by the trance mind and other dissociated states of consciousness.1 In "crystal visions" we have it in a more or less isolated form. Likewise the heightening of the imagination and its freedom from the restrictions of time and space, which Mrs. Arnold-Forster interestingly dwells upon, find their analogues in dissociated states of mind other than sleep. It would be easy to cite examples of the day-dreamer or trance-dreamer in whose fantasies "distance is annihilated" and centuries passed over in the twinkling of an eye. As in normal dreams, the soul may seem to leave the body and hover in space or be transported to another sphere - celestial or cosmic.

In similar fashion I might point out that in such states are found the analogues of other dream phenomena, such as symbolisms, the solution of problems - mathematical and personal - literary manifestations of creative imagination, ascribed by Robert Louis Stevenson to his "Brownies" somewhere beneath or outside the dream mind, the doubling of the conscious self (manifested by the activity of a second consciousness, or the "Guide" in the author's dreams - Chapter XIII), defence reactions, visions, and other hallucinations.

1 "The Unconscious," Section II.

So, though normal dreams are of value for the light they throw on the phenomena of abnormal psychology, still more the manifold and varied data of the latter, the larger field and subject to experimentation, give an understanding of the former. This is the reverse of the point of view of the Freudian psychology. The latter subjects itself to the errors and fallacies necessarily arising from the acceptation of, and dogmatic adherence to, a theory which is true of only particular types of dreams, and therefore limited in its applications.

Not the least interesting as well as novel of the dream phenomena recorded by the author are those of "dream control" and flying dreams. The fact that Mrs. Arnold-Forster has succeeded in con-strolling her dreams, at least to the extent of pro-Tiibiting unpleasant dreams, and teaching herself to fly, will be a novel contribution to most students. Both phenomena have interesting corollaries: the former involves the implication of the principles of doubling of consciousness and the "censor," and the latter of dissociation of all sensory impressions including what is known as coenesthesia, or the organic sensations streaming from the viscera and other parts of the body. At least so flying dreams can be explained. If we assume that all such sensations are completely dissociated from the dream mind, so that the latter become pure thought and images (for there is evidence that during ordinary sleep such impressions are still received), we have a mental condition suitable for the creative imagination to fabricate the illusion of flying, untrammelled by any conflict with sensory impressions of reality!. Mrs. Arnold-Forster, herself, has apparently experienced such a dream without the flying illusion, judging from her description (p. 151). Such complete dissociation of all consciousness of the body finds its analogue, as I have observed, in a waking dissociated state, in which the subject describes herself as just "thought in space" without a body.

Given such a dissociation, it would theoretically only require a creative imagination with vivid imagery to fabricate the illusions or hallucinations of objective flying. The mind is capable of creating almost any kind of hallucination even to the extent of shaking hands with an imaginary "spirit," provided it is not contradicted by the conflicting awareness of reality.

It is insisted by those who hold certain theories regarding the mechanism of dreams, particularly by the school of psycho-analysts, that their theories are "purely inductive, being built up" (as a brilliant expounder writes) "step by step on the basis of actual experiences without the introduction of any a priori speculative hypotheses," Conceding this, and disregarding the fact that many of the alleged facts of experience are actually not facts but interpretations of facts, it still remains true that the same can be said for contending theories. Each is an inductively reached conclusion. The explanation of such differing theories is that each is based on different facts of experience. All theories as well as hypotheses of science hold good only until newly discovered facts require reconsideration and new explanations. Thus the older theories of atoms and the ultimate nature of matter held good until the discovery of new facts required a re-examination of the theories and a new formulation of conceptions in terms of electrons and electricity.