Definition
Rational belief revision is the deliberate practice of updating what you believe in response to evidence — and only to evidence. Beliefs typically resist updating: the mind protects them with selective attention, post-hoc rationalization, and emotional commitment. Rational revision counters that protection by treating each belief as provisional and demanding it earn its continued residence.
Maxwell Maltz wrote in the era before Bayesian language was common, but the underlying instruction is the same: a belief is a hypothesis about reality, not a permanent feature of the self. When new data contradicts the hypothesis, the responsible move is to amend the hypothesis. The unwillingness to amend is what locks limiting beliefs in place across decades.
Why it matters
How it works
The practice runs on three moves. First, surface the belief as a sentence rather than a feeling — "I believe I am bad at small talk," not just a vague dread of parties. Second, audit the evidence for and against. Distinguish facts (specific events, observed outcomes) from opinions (interpretations, inherited verdicts, vague memories). Third, write the revised belief — narrower, more accurate, more useful — and treat it as the new hypothesis.
Maltz's contribution was to insist that the revised belief then be installed via mental rehearsal, not merely stated. The cybernetic system needs the new picture vividly imagined, not just logically endorsed. Repetition seals the revision.