Peculiarities in the material I have used to elucidate the interpretation of dreams have rendered this publication difficult. From the work itself it will appear why all dreams related in the literature or collected by others had to remain useless for my purpose; for examples I had to choose between my own dreams and those of my patients who were under psychoanalytic treatment. I was restrained from utilising the latter material by the fact that in it the dream processes were subjected to an undesirable complication on account of the intermixture of neurotic characters. On the other hand, inseparably connected with my own dreams was the circumstance that I was obliged to expose more of the intimacies of my psychic life than I should like and than generally falls to the task of an author who is not a poet but an investigator of nature. This was painful, but unavoidable; I had to put up with the inevitable in order not to be obliged to forego altogether the demonstration of the truth of my psychological results. To be sure, I could not at best resist the temptation of disguising some of my indiscretions through omissions and substitutions, and as often as this happened it detracted materially from the value of the examples which I employed. I can only express the hope that the reader of this work, putting himself in my difficult position, will show forbearance, and also that all persons who are inclined to take offence at any of the dreams reported will concede freedom of thought at least to the dream life. PREFACE TO THE SECOND EDITION If there has arisen a demand for a second edition of this rather difficult book before the end of the first decade, I owe no gratitude to the interest of the professional circles to whom I appealed in the preceding sentences. My colleagues in psychiatry, apparently, have made no effort to shake off the first surprise which my new conception of the dream evoked, and the professional philosophers, who are accustomed to treat the problem of dream life as a part of the states of consciousness, devoting to it a few—for the most part identical—sentences, have apparently failed to observe that in this field could be found all kinds of things which would inevitably lead to a thorough transformation of our psychological theories. The behaviour of the scientific critics could only justify the expectation that this work of mine was destined to be buried in oblivion; and the small troop of brave pupils who follow my leadership in the medical application of psychoanalysis, and also follow my example in analysing dreams in order to utilise these analyses in the treatment of neurotics, would not have exhausted the first edition of the book. I therefore feel indebted to that wider circle of intelligent seekers after truth whose co-operation has procured for me the invitation to take up anew, after nine years, the difficult and in so many respects fundamental work.