I have no theory to offer the reader in explanation of my faculty, —at least in so far as its physiological aspect is concerned. Of course, having received a medical education, I have speculated about the modus operandi of the phenomenon, but my speculations are not of such a character as to entitle them to presentation in the form even of an hypothesis. I am tolerably well acquainted with most of the propositions regarding unconscious cerebration, which have been put forward by men of science, but none of these propositions can, by any process of reasonable expansion or modification, be made to fit my case. Hysteria, to the multiform and manifold categories of which, medical experts are wont to refer the majority of the abnormal experiences encountered by them, is plainly inadequate to explain or account for mine. The singular coherence and sustained dramatic unity observable in these dreams, as well as the poetic beauty and tender subtlety of the instructions and suggestions conveyed in them do not comport with the conditions characteristic of nervous disease. Moreover, during the whole period covered by these dreams, I have been busily and almost continuously engrossed with scientific and literary pursuits demanding accurate judgment and complete self-possession and rectitude of mind. At the time when many of the most vivid and remarkable visions occurred, I was following my course as a student at the Paris Faculty of Medicine, preparing for examinations, daily visiting hospital wards as dresser, and attending lectures. Later, when I had taken my degree, I was engaged in the duties of my profession and in writing for the press on scientific subjects. Neither have I ever taken opium, hashish or other dream-producing agent. A cup of tea or coffee represents the extent of my indulgences in this direction. I mention these details in order to guard against inferences which otherwise might be drawn as to the genesis of my faculty.
With regard to the interpretation and application of particular dreams, I think it best to say nothing. The majority are obviously allegorical, and although obscure in parts, they are invariably harmonious, and tolerably clear in meaning to persons acquainted with the method of Greek and Oriental myth. I shall not, therefore, venture on any explanation of my own, but shall simply record the dreams as they passed before me, and the impressions left upon my mind when I awoke.