Page:Mind (New Series) Volume 6.djvu/300

 284 NOTES. Such dreams usually present a possible, though, it may be, highly improbable event. The half-waking or hypnagogic intelligence seems to be deceived by this element of life-like possibility. 1 Consequently a fallacy of perception takes place strictly comparable to the fallacious perception which in the case of an external sensation we call an illusion. In the ordinary illusion an externally excited sensation of one kind is mistaken for an externally excited sensation of another kind. In this case a centrally excited sensation of one order (dream image) is mis- taken for a centrally excited sensation of another order (memory). The phenomenon is, therefore, a mental illusion belonging to the group of false memories, and it may be termed hypnagogic paramnesia. 2 The process seems to have a certain interest, and it may throw light on some rather obscure phenomena. It sometimes happens that we are able to recall a vivid dream, usually, I believe, a fairly probable dream, with no idea as to when it was dreamed. And it sometimes happens that we find ourselves in possession of experiences of which we cannot certainly say that they happened in waking life or in dream life. In such cases it seems probable that this hypnagogic paramnesia has come into action ; the half -waking consciousness dismisses the vivid and life-like dream as an old and familiar experience, shunting it off into temporary forgetfulness, unless some accident again brings it into consciousness with, as it were, a fragment of that wrong label still sticking to it. Such a paramnesic process may thus also help to account for the mighty part which, as so many thinkers from Aristotle and Augustine downwards have seen, dreams have played in moulding human action and human belief. It is a means whereby waking life and dream life are brought to an apparently common level. II. But another point is suggested by this phenomenon of the half -awake consciousness. If it may be regarded as a variety of paramnesia. may it not serve to throw some light on that much-discussed phenomenon which has led to so many strange and complicated theories ? 3 I think it may. 1 Dr. Marie de Mauaceine, who has lately studied the phenomena of the hypnagogic state experimentally in much detail, finds that it is characterised by abnormal suggestibility, and she considers it almost identical with the hypnotic state. 2 By hypnagogic paramnesia I mean a false memory occurring in the antechamber of sleep, but not necessarily before sleep. Mr. Myers' invention of the word " hypnopompic '' seems to me unnecessary except for pedantic reasons. I take the condition of consciousness to be almost the same whether the sleep is coming on or passing away. In the dream I have recorded it is even impossible to say whether the phe- nomenon is " hypnagogic " or " hypnopompic " ; in such a case the twilight consciousness is as much conditioned by the sleep that is passing away as by the sleep that is corning on. 3 It is needless to enumerate these, but I may refer to the simplest, viz., that the false memory is an unrecognised true memory. This is the explanation chiefly relied on by Jessen, Sander, Emminghaus, Sully, and Burnham. Undoubtedly it will explain a considerable proportion of cases but not the really typical cases in which the subject has an overwhelming conviction that even the minute details of the present.