Psychoanalysis has achieved much since "The Interpretation of Dreams," yet it would be nothing without this powerful fountainhead of creative insights, without this monumental symbolic landmark of an entire intellectual century, of an entire culture. Freud's famous phrase that "the dream is the royal road to the unconscious" reveals the traces of his endeavor. Alongside the deciphering of the dream, he inevitably leads to the discovery of the important elements of his theory, which make their debut within the pages of "Traumdeutung": the Oedipus complex, the unconscious, neurosis, regression, and more.

The dream will no longer be attributed to a single factor, such as a physical, perceptual stimulus, or a day’s concern. Its genesis will involve a multitude of heterogeneous factors within the unparalleled interplay of the renowned "dream work," behind which, of course, Freudian insight will identify – steadfastly present, the hallmark of an entire species and culture – the unconscious desire.

There are no indifferent dream stimuli, nor are there innocent dreams. This is my unwavering and exclusive opinion, except for the dreams of children and perhaps the brief dream reactions to nighttime excitations. Anything else we dream can clearly be recognized as psychically significant or distorted, and must only be assessed after the interpretation of the dream is completed, at which point it will again be shown to be significant. The dream does not concern itself with trivialities; we do not allow the insignificant to disturb our sleep. The so-called innocent dreams prove to be dreadful if we take the trouble to interpret them; if I may say so, the dream is "the pear with the tail behind."

In attempting to present in this book the interpretation of dreams, I believe I do not exceed the framework of neuro-pathological interests. This is because psychological examination shows that the dream is the first member of a series of abnormal psychic formations, whose other members, hysterical phobia, obsessive-compulsive disorder, and paranoid fantasy, must, for practical reasons, engage the physician. The dream cannot claim a similar practical significance; however, it has much greater value as a model, while anyone who does not know how to explain the genesis of dream images will vainly try to understand phobias, obsessions, and paranoid ideas, and possibly to therapeutically influence them.

Sigmund Freud