Mental Models Dictionary
Charlie Munger's cognitive biases and thinking tools. A searchable reference for better decision-making.
Core Thinking Tools
Inversion
Ask "What would guarantee failure?" instead of "How do I succeed?"
Approach problems backwards by asking what would guarantee failure.
Learn more →Circle of Competence
Knowing what you don't know is more useful than being brilliant.
Know the boundaries of what you truly understand.
Learn more →Second-Order Thinking
Ask "And then what?" repeatedly before acting.
Consider the consequences of consequences.
Learn more →Probabilistic Thinking
Assign probabilities to outcomes and update them as evidence changes.
Think in ranges of outcomes with probabilities, not certainties.
Learn more →First Principles Thinking
Question every assumption until you reach fundamental truths.
Break problems down to fundamental truths and rebuild from there.
Learn more →The 25 Cognitive Biases
From Munger's "Psychology of Human Misjudgment" — systematic ways humans reliably misjudge.
Reward & Punishment Superresponse
People respond powerfully to incentives—often in unintended ways.
Learn more → ASSOCIATIONLiking/Loving Tendency
We overlook faults of what we love and distort facts in their favor.
Learn more → ASSOCIATIONDisliking/Hating Tendency
We ignore virtues of what we dislike and distort facts against them.
Learn more → DECISIONDoubt-Avoidance Tendency
We make quick decisions to escape the discomfort of uncertainty.
Learn more → DECISIONInconsistency-Avoidance Tendency
We resist changing established beliefs, habits, and behaviors.
Learn more → SOCIALReciprocation Tendency
We feel compelled to return favors and slights.
Learn more → SOCIALSocial Proof Tendency
When uncertain, we look to others' actions for guidance.
Learn more → INFORMATIONAvailability Misweighing
We overweight information that's recent, vivid, or easily recalled.
Learn more → SOCIALAuthority Misinfluence
We defer excessively to perceived authority.
Learn more → LOSSDeprival Superreaction
Losses hurt approximately twice as much as equivalent gains please.
Learn more → SELFExcessive Self-Regard Tendency
We systematically overestimate our abilities and prospects.
Learn more → SELFOver-Optimism Tendency
We systematically overestimate favorable outcomes.
Learn more → DECISIONCommitment & Consistency Bias
Once committed, we defend positions beyond reason.
Learn more → INFORMATIONContrast Misreaction
We judge relative to recent comparisons, not absolute standards.
Learn more → INFORMATIONAnchoring Tendency
First information disproportionately influences subsequent judgment.
Learn more → SOCIALEnvy/Jealousy Tendency
Comparison with others drives irrational behavior.
Learn more → ASSOCIATIONSimple Association Tendency
We associate messengers with their messages.
Learn more → STATEStress Influence
Stress amplifies other biases and impairs judgment.
Learn more → SOCIALReason-Respecting Tendency
We comply more readily when given reasons—even bad ones.
Learn more → METALollapalooza Effect
Multiple biases combining create extreme, often irrational outcomes.
Learn more →Essential Munger Quotes
"In my whole life, I have known no wise people who didn't read all the time—none, zero."
"The big money is not in the buying and selling, but in the waiting."
"It is remarkable how much long-term advantage people like us have gotten by trying to be consistently not stupid, instead of trying to be very intelligent."
"I never allow myself to hold an opinion on anything that I don't know the other side's argument better than they do."
Deep Dive
Complete guide to Munger's latticework, investment philosophy, and the Buffett partnership.
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