The first edition begins:
"In the following pages, I shall demonstrate that there exists a psychological technique by which dreams may be interpreted and that upon the application of this method every dream will show itself to be a senseful psychological structure which may be introduced into an assignable place in the psychic activity of the waking state. I shall furthermore endeavor to explain the processes which give rise to the strangeness and obscurity of the dream, and to discover through them the psychic forces, which operate whether in combination or opposition, to produce the dream. This accomplished by investigation will terminate as it will reach the point where the problem of the dream meets broader problems, the solution of which must be attempted through other material."[19]
Freud begins his book in the first chapter titled "The Scientific Literature on the Problems of the Dream" by reviewing different scientific views on dream interpretation, which he finds interesting but not adequate.[20] He then makes his argument by describing a number of dreams which he claims illustrate his theory.
Much of Freud's sources for analysis are in literature. Many of his most important dreams are his own — his method is inaugurated with an analysis of his dream "Irma's injection" — but many also come from patient case studies.
