The Interpretation of Dreams by Sigmund Freud Chapter 1 Page 33

found among adults also, but, as mentioned, these are mostly exactly like the manifest content. Thus, a random selection of persons will generally respond to thirst at night-time with a dream about drinking, thus striving to get rid of the sensation and to let sleep continue. Many persons frequently have these comforting dreams before waking, just when they are called. They then dream that they are already up, that they are washing, or already in school, at the office, etc., where they ought to be at a given time. The night before an intended journey one not infrequently dreams that one has already arrived at the destination; before going to a play or to a party the dream not infrequently anticipates, in impatience, as it were, the expected pleasure.

At other times the dream expresses the realization of the desire