- 1: to bring into accord with reason or cause something to seem reasonable: as
- a : to substitute a natural for a supernatural explanation of <rationalize a myth>
- b : to attribute (one's actions) to rational and creditable motives without analysis of true and especially unconscious motives <rationalized his dislike of his brother> ; broadly : to create an excuse or more attractive explanation for <rationalize the problem>
- 2: to free (a mathematical expression) from irrational parts <rationalize a denominator>
- 3: to apply the principles of scientific management to (as an industry or its operations) for a desired result (as increased efficiency)
In psychology and logic, rationalization (or making excuses) is an informal fallacy of reasoning in which one constructs a logical justification for a belief, decision, action or lack thereof that was originally arrived at through a different mental process. It is a defense mechanism in which perceived controversial behaviors or feelings are explained in a rational or logical manner to avoid the true explanation of the behavior or feeling in question.
This process can be in a range from fully conscious (e.g. to present an external defense against ridicule from others) to mostly subconscious (e.g. to create a block against internal feelings of guilt).
According to the DSM-IV rationalization occurs "when the individual deals with emotional conflict or internal or external stress by concealing the true motivations for his or her own thoughts, actions, or feelings through the elaboration of reassuring or self serving but incorrect explanations."