reality principle: Meaning and Definition of

real'ity prin"ciple

Pronunciation: [key]
— Psychoanal. Psychoanal.
  1. the motivating force or mechanism by which the child, who has previously sought immediate gratification of all wishes, realizes that gratification must sometimes be deferred or forgone.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.