"There are some people who are quite clearly aware during the night tht they are alseep and dreaming and who thus seem to possess the faculty of consciously directing their dreams. If, for instance, a dreamer of this kind is dissatisfied with the turn taken by a dream he can break it off without waking up and start it again in another direction - just as a popular dramatist may under pressure give his play a happier ending."

-Freud, 1954