Irrational Beliefs are defined as personal truths that aren't grounded in reality. An example of such a belief is that one must be loved and approved of by everyone in order to be happy or to have a sense of self-worth. This is irrational because it cannot possibly be achieved.

"Irrational beliefs" were identified by Albert Ellis, in his Rational Emotive Behavior Therapy (REBT) approach which, if held, lead to distressing emotional states, and maladaptive behaviors.