There has been a great deal of study by psychologists of the operation of the unconscious upon the conscious, but much less of the operation of the conscious upon the unconscious.
 Bertrand Russell, The Conquest of Happiness (1930). copy citation

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Author Bertrand Russell
Source The Conquest of Happiness
Topic study unconscious
Date 1930
Language English
Reference
Note
Weblink http://russell-j.com/beginner/COH-TEXT.HTM

Context

“This has ‘its importance, first because it makes it possible to get through the day’s work with less expenditure of thought, secondly because it affords a cure for insomnia, and thirdly because it promotes efficiency and wisdom in decisions. But methods of this kind do not touch the subconscious or the unconscious, and when a trouble is grave no method is of much avail unless it penetrates below the level of consciousness. There has been a great deal of study by psychologists of the operation of the unconscious upon the conscious, but much less of the operation of the conscious upon the unconscious. Yet the latter is of vast importance in the subject of mental hygiene, and must be understood if rational convictions are ever to operate in the realm of the unconscious. This applies in particular in the matter of worry.” source