For disagreeable things are not intended to be represented by the dream; painful thoughts that have occurred during the day can force their way into the dream only if they lend a cloak to the wish-fulfilment.
 Sigmund Freud, The Interpretation of Dreams (1899). copy citation

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Author Sigmund Freud
Source The Interpretation of Dreams
Topic fulfilment force
Date 1899
Language English
Reference
Note Translated by A. A. Brill
Weblink http://www.bartleby.com/285/6.html

Context

“According to the theory of wish-fulfilment this dream could not have happened had not the suppressed, but at the same time pleasurable, train of thought concerning personal aggrandisement been coupled with the opposing thoughts of disgust. For disagreeable things are not intended to be represented by the dream; painful thoughts that have occurred during the day can force their way into the dream only if they lend a cloak to the wish-fulfilment. The dream activity can dispose of the affects in the dream thoughts in still another way, besides admitting them or reducing them to zero. It can change them into their opposite. We have already become acquainted with the rule of interpretation that every element of the dream may be interpreted by its opposite, as well as by itself.” source