The Interpretation of Dreams by Sigmund Freud Chapter 3 Page 6

from the answer which, though within my knowledge, belongs elsewhere.

If I subject the dream of another person instead of one of my own to analysis, the result is the same; the motives for convincing others is, however, changed. In the dream of a healthy person the only way for me to enable him to accept this repressed idea is the coherence of the dream thoughts. He is at liberty to reject this explanation. But if we are dealing with a person suffering from any neurosis — say from hysteria — the recognition of these repressed ideas is compulsory by reason of their connection with the symptoms of his illness and of the improvement resulting from exchanging the symptoms for the repressed ideas. Take the patient from whom I got the last dream about the three tickets for one florin fifty kreuzers.