The Interpretation of Dreams by Sigmund Freud Chapter 2 Page 13

Just as one element of the dream leads to associations with several dream thoughts, so, as a rule, the one dream thought represents more than one dream element. The threads of the association do not simply converge from the dream thoughts to the dream content, but on the way they overlap and interweave in every way.

Next to the transformation of one thought in the scene (its “dramatization”), condensation is the most important and most characteristic feature of the dream work. We have as yet no clue as to the motive calling for such compression of the content.

In the complicated and intricate dreams with which we are now concerned, condensation and dramatization do not wholly account for the difference between dream contents and dream thoughts. There is evidence of a