[235] The explanation of paramnesia here set forth received on its first publication the approval of Léon Marillier, who considered it 'ingenious and seductive,' and as adequately accounting for the phenomena, provided we bear in mind that the loss of a clear feeling of time is characteristic of hypnagogic and allied states, the perception of each moment being immediately transferred into an ancient memory, and consequently recognised (L'Année Biologique, third year, 1897, p. 772). This necessity for taking into account the co-existence of perception and illusory remembrance has largely moulded several of the theories of paramnesia. Thus Jean de Pury (Archives de Psychologie, December 1902), while affirming that pseudo-reminiscence is due to an anteriorisation of actual perceptions, regards it as of the nature of a double refraction such as that simultaneously produced on two faces of a prism by the same image; under the influence of conditions he is unable to define, an image appears for the moment on the plane both of the past and of the present, and psychically we see double just as physically we see double when the parallelism of our visual rays is disturbed. Piéron, again, taking up a theory at one time favoured by Dugas, and previously suggested in one form or another by Ribot and Fouillée, assumes the formation of two images: one which, owing to distraction or fatigue, reaches consciousness after having traversed subconsciousness, and so takes on a dream-like and effaced character, and almost simultaneously with this a direct perception which has not thus changed its character; the shock of the conflict between these two produces the pseudo-reminiscence ('Sur l'Interpretation des Faits de Paramnésie,' Revue Philosophique, August 1902). Albès, in his Paris thesis, criticises this explanation, pointing out that a sequence of this kind very frequently occurs, but produces no pseudo-reminiscence.
[236] Michel Léon-Kindberg, 'Le Sentiment du Déjà Vu,' Revue de Psychiatrie, April 1903, No. 4.
[237] G. Ballet, 'Un Cas de Fausse Reconnaissance,' Revue Neurologique, 1904, p. 1221.
[238] Dugas, 'Observations sur des Erreurs "Formelles" de la Mémoire', Revue Philosophique, July 1908; ib. June 1910. Dugas makes no reference to Janet, nor to my paper on Hypnagogic Paramnesia, but his statement of the matter to some extent combines and harmonises those of the two earlier writers.
[239] P. Janet, 'A Propos du Déjà Vu,' Journal de Psychologie Normale et Pathologique, July-August 1905.
[240] H. Bergson, 'Le Souvenir du Présent et la Fausse Reconnaissance,' Revue Philosophique, December 1908. It should be remarked that, except in the attempt to explain why paramnesia is not normally habitual, Bergson's paper is based on the ideas or suggestions of previous writers.
[241] Before the appearance of my paper, as already mentioned, Anjel had emphasised the significance of fatigue in the production of paramnesia (Archiv für Psychiatrie, Bd. viii. pp. 57 et seq.). His theory, indeed (only known to me through brief summaries)—according to which the pseudo-reminiscence is due to the tardy apprehension by the fatigued mind of a sensation which is thus degraded to the level of a reproduced impression—seems practically identical with that which I independently reached in the light of hypnagogic phenomena.
[242] I disregard those theories which invoke histological explanations, as by some peculiar disposition of the neurons. Such explanations are as much outside the psychologist's sphere as the old-fashioned explanations by reference to God and the Devil. A known physiological or pathological process may, indeed, quite properly be recognised by the psychologist; such, for instance, as the disturbance of the heart associated with some dreams. Even minute changes in the brain, when they have been properly determined by the histologist, may be effectively invoked by the psychologist if they seem to supply an exact physical correlative to his own findings. But for the psychologist to go outside his own field, and invent a purely fanciful and arbitrary neuronic scheme to suit a psychic process, explains nothing. It is merely child's play. The stuff that the psychologist works with must be psychical, just as the stuff of the physicist's work must be physical.
[243] Certain phases of waking psychic life are, however, closely related to dreaming. This is obviously the case as regards day-dreaming or reverie. (See e.g. Janet, Névroses et Idées Fixes, vol. i. pp. 390-6.) It would also appear that wit is the result of a process analogous to that fusion of incompatible elements which we have found to prevail in dreams. Our dreams are sometimes full of usually ineffective wit; I could easily quote dreams in illustration. (Freud has, from his point of view, studied the analogy between wit and dreaming in Der Witz und seine Beziehung zum Unbewussten.)
[244] In more recent times Moreau of Tours, especially, argued (Du Haschich et de l'Aliénation Mentale, 1845) that haschisch-intoxication is insanity, and that insanity is a waking dream.