studies of his own dreams, but the great body of material accumulated by him and his school is derived from the dreams of the neurotic. Thus Stekel states that he has analysed many thousand dreams, but his lengthy study on the interpretation of dreams deals exclusively with the dreams of the neurotic.[155] Stekel believes, moreover, that from the structure of the dream life conclusions may be drawn, not only as to the life and character of the dreamer, but also as to his neurosis, the hysterical person dreaming differently from the obsessed person, and so on. If that is the case we are certainly justified in doubting whether conclusions drawn from the study of the dreams of neurotic people can be safely held to represent the normal dream life, even though it may be true that there is no definite frontier between them. Whatever may be the case among the neurotic, in ordinary normal sleep the images that drift across the field of consciousness, though they have a logic of their own, seem in a large proportion of cases to be quite explicable without resort to the theory that they stand in vital but concealed relationship to our most intimate self. Even in waking life, and at normal moments which are not those of reverie, it seems possible to trace the appearance in the field of consciousness of images which are evoked neither by any known mental or physical circumstance of the moment, or any hidden desire, images that are as disconnected from the immediate claims of desire and even of association as those of dreams seem so largely to be. It sometimes occurs to me--as doubtless it occurs to other people--that at some moment when my thoughts are normally occupied with the work immediately before me, there suddenly appears on the surface of consciousness a totally unrelated picture. A scene arises, vague but usually recognisable, of some city or landscape--Australian, Russian, Spanish, it matters not what--seen casually long years ago, and possibly never thought of since, and possessing no kind of known association either with the matter in hand or with my personal life generally. It comes to the surface of consciousness as softly, as unexpectedly, as disconnectedly, as a minute bubble might arise and break on the surface of an actual stream from ancient organic material silently disintegrating in the depths beneath.[156] Every one who has travelled much cannot fail to possess, hidden in his psychic depths, a practically infinite number of such forgotten pictures, devoid of all personal emotion. It is possible to maintain, as a matter of theory, that when they come up to consciousness, they are evoked by some real, though untraceable, resemblance which they possess to the psychic or physical state existing when they reappear. But that theory cannot be demonstrated. Nor, it may be added, is it more plausible than the simple but equally unprovable theory that such scenes do really come to the surface of