Decision-Making Models

Mental models specifically for making better decisions under uncertainty. These frameworks help you evaluate options systematically, anticipate consequences, ma

Mental models specifically for making better decisions under uncertainty. These frameworks help you evaluate options systematically, anticipate consequences, manage risk, and avoid the cognitive biases that derail judgment.

Browse all mental models for this use case below. Each model includes a practical explanation, a historical case study, real-world examples, and an interactive exercise.

Inversion

Instead of asking how to succeed, ask what would guarantee failure — then avoid it.

Foundation General Thinking

Second-Order Thinking

Consider not just the immediate consequences of a decision, but the consequences of those consequences.

Foundation General Thinking

Circle of Competence

Know what you know, know what you don't know, and stay honest about the boundary.

Foundation General Thinking

Pre-Mortem

Before starting, imagine the project has already failed. Then figure out why.

Foundation General Thinking

Probabilistic Thinking

Think in likelihoods, not certainties. Assign probabilities to outcomes instead of assuming binary results.

Intermediate Mathematics

Feedback Loops

Every system has outputs that feed back into inputs — reinforcing or balancing the system's behaviour over time.

Intermediate Systems Thinking

Margin of Safety

Build a buffer between what you expect and what you plan for. The world will surprise you.

Foundation General Thinking

Opportunity Cost

The true cost of anything is whatever you give up to get it — including the next best alternative.

Foundation Economics

Antifragility

Some things don't just survive shocks — they get stronger from them. Position yourself to benefit from disorder.

Intermediate Systems Thinking

Eisenhower Matrix

Separate what's urgent from what's important. Most people spend their lives on the wrong quadrant.

Foundation General Thinking

Bayesian Updating

Start with your best guess, then update it proportionally as new evidence arrives.

Intermediate Mathematics

Confirmation Bias

We instinctively seek out information that confirms what we already believe — and ignore what contradicts it.

Foundation Psychology

Loss Aversion

Losses hurt roughly twice as much as equivalent gains feel good — and this asymmetry distorts nearly every decision you make.

Intermediate Psychology

Comparative Advantage

Do what you're relatively best at, even if someone else is absolutely better at everything.

Intermediate Economics

Supply and Demand

The price and availability of anything — goods, jobs, attention, ideas — is shaped by how much exists relative to how much is wanted.

Foundation Economics

Natural Selection

What works survives; what doesn't, disappears. This principle applies far beyond biology — to ideas, businesses, and habits.

Intermediate Biology

Critical Mass

Some processes need a minimum threshold of input before anything happens — then they suddenly accelerate.

Intermediate Physics

Regret Minimisation

Project yourself to age 80 and ask which choice you'll regret not making. That's usually the right one.

Foundation General Thinking

Marginal Thinking

Don't evaluate the total — evaluate the next unit. The value of one more hour, one more dollar, one more feature is what matters.

Intermediate Economics

Pareto Principle

Roughly 80% of effects come from 20% of causes. Find the vital few and ignore the trivial many.

Foundation General Thinking

Sunk Cost Fallacy

Money, time, or effort already spent should not influence future decisions — but it almost always does.

Foundation Economics

Thinking in Bets

Separate decision quality from outcome quality. A good decision can have a bad outcome, and vice versa.

Intermediate Psychology

Via Negativa

Improve by removing what's harmful rather than adding what might help. Subtraction often beats addition.

Intermediate General Thinking

Anchoring

The first piece of information you encounter disproportionately shapes all subsequent judgments.

Foundation Psychology

Availability Heuristic

We judge the likelihood of events by how easily examples come to mind — not by actual frequency.

Foundation Psychology

Framing Effect

The same information presented differently leads to different decisions — even when the underlying facts are identical.

Intermediate Psychology

Goodhart's Law

When a measure becomes a target, it ceases to be a good measure.

Intermediate Systems Thinking

Compounding

Small consistent gains accumulate into extraordinary results over time — in finance, skills, relationships, and knowledge.

Foundation Mathematics

Normal Distribution

Most outcomes cluster around the average, with extreme outcomes being rare — except when they are not.

Intermediate Mathematics

Asymmetric Risk

Seek decisions where the potential upside vastly outweighs the potential downside — even if success is unlikely.

Intermediate Economics

Narrative Fallacy

Humans compulsively construct stories to explain random events, creating false causation and illusory patterns.

Intermediate Psychology

Circle of Control

Focus your energy on what you can control, accept what you cannot, and learn to tell the difference.

Foundation General Thinking

Local vs Global Optima

The best option within your current constraints may not be the best option overall — sometimes you need to get worse before you can get better.

Intermediate Mathematics

Chesterton's Fence

Before removing something, understand why it was put there in the first place.

Foundation General Thinking

Cobra Effect

Well-intentioned interventions often produce the opposite of their intended effect when people respond strategically to new incentives.

Intermediate Systems Thinking
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Adverse Selection

When one side of a market has more information, the people most likely to participate are those who benefit most — often at the other side's expense.

Intermediate Economics

Affect Heuristic

We make judgments based on current emotions rather than objective analysis — if something feels scary, we overestimate its risk.

Intermediate Psychology

Anchoring and Adjustment

We start from an initial value (the anchor) and adjust insufficiently from it — our final estimate stays too close to the starting point.

Foundation Psychology

Asymmetric Information

One party in a transaction knows more than the other. This imbalance drives much of economic behaviour.

Intermediate Economics
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Bandwagon Effect

The tendency to adopt beliefs and behaviours simply because many other people do.

Foundation Psychology

Barbell Strategy

Combine extreme safety with small, high-upside bets. Avoid the dangerous middle.

Intermediate Economics

Base Rate Neglect

We ignore how common or rare something is in general, and focus too much on the specific case in front of us.

Intermediate Mathematics
P

Base Rates and Priors

Before evaluating specific evidence, check how common the thing is in general. The base rate is your starting point.

Intermediate Mathematics
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Building a Second Brain

Offload information from your biological memory to an external system so your brain can focus on thinking, not remembering.

Foundation General Thinking

Chesterton's Fence (Revisited)

Before removing something that seems useless, understand why it was put there. It may serve a purpose you haven't noticed.

Foundation General Thinking
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Circle of Influence

Focus energy on what you can control, not what you can't. Most worry is spent on the wrong circle.

Foundation Psychology

Counterfactual Thinking

Ask 'what if things had been different?' to separate skill from luck and find the real causes.

Intermediate General Thinking
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Decoy Effect

Adding a clearly inferior option makes one of the other options look more attractive by comparison.

Intermediate Psychology

Devil's Advocate

Deliberately argue the opposing side to stress-test your own position.

Foundation General Thinking

Diminishing Returns

Each additional unit of input produces less additional output. The first hour of practice helps more than the hundredth.

Foundation Economics

Disagree and Commit

When consensus can't be reached and the decision is reversible, it's better to commit to one direction and learn from results than to debate indefinitely.

Foundation General Thinking
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Distinction Bias

When comparing options side by side, we notice differences that wouldn't matter in actual use. The comparison mode distorts our evaluation.

Intermediate Psychology
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Endowment Effect

We value things more once we own them — simply possessing something increases its perceived worth.

Foundation Psychology

Ergodicity

The average outcome for a group can be completely different from the typical outcome for an individual over time.

Advanced Mathematics
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Expected Value

Multiply each possible outcome by its probability and sum them. The mathematically optimal choice is the one with the highest expected value.

Intermediate Mathematics
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Gambler's Fallacy

Believing that past random events affect the probability of future random events — that a coin 'is due' for heads after several tails.

Foundation Psychology
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Goodness of Fit

The best model isn't the most complex or the most elegant — it's the one that best fits your specific situation.

Intermediate General Thinking

Halo Effect

A positive impression in one area creates a biased positive impression in unrelated areas.

Foundation Psychology

Hindsight Bias

After something happens, we convince ourselves we knew it all along — even when we didn't.

Foundation Psychology

Hyperbolic Discounting

We strongly prefer immediate rewards over future ones, even when waiting would give us much more. $100 today feels better than $120 next month.

Foundation Psychology

Iatrogenics

Sometimes the intervention causes more harm than the problem. The cure can be worse than the disease.

Intermediate Biology
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IKEA Effect

We overvalue things we helped create, regardless of their objective quality.

Foundation Psychology

Incentive-Caused Bias

Never ask someone for their opinion on something when their income depends on giving you a particular answer.

Foundation Psychology

Irreversibility

Some decisions can be undone; others can't. The irreversible ones deserve disproportionate care.

Foundation General Thinking

Leverage

Small inputs that produce disproportionately large outputs. Time, capital, code, media, and labour can all be leveraged.

Foundation General Thinking
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Market for Lemons

When buyers can't distinguish quality, sellers of high-quality goods exit the market because they can't get fair prices — leaving only low-quality goods.

Intermediate Economics

Mental Accounting

We treat money differently depending on where it came from or what we've labelled it, even though a dollar is a dollar.

Intermediate Economics
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Mere Exposure Effect

We prefer things simply because we've been exposed to them repeatedly — familiarity breeds liking, not contempt.

Foundation Psychology
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Mimetic Desire

We don't want things independently — we want things because other people want them. Desire is borrowed, not original.

Intermediate Psychology

Minimum Effective Dose

Find the smallest input that produces the desired result. More is not always better — sometimes it's waste.

Foundation General Thinking

Negativity Bias

We give more weight to negative experiences, information, and emotions than to equally positive ones.

Foundation Psychology

Niche Construction

Instead of just adapting to your environment, actively shape it to suit your strengths.

Intermediate Biology

Optionality

Create situations with limited downside and unlimited upside. Keep your options open until you have to commit.

Intermediate Economics
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Paradox of Choice

More options don't always make us happier — beyond a threshold, additional choices increase anxiety, regret, and decision paralysis.

Foundation Psychology

Path Dependence

Where you end up depends heavily on where you started and the sequence of steps taken — not just the destination's inherent qualities.

Intermediate Systems Thinking
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Peak-End Rule

We judge experiences primarily by their most intense moment and their ending — not by the average or total.

Intermediate Psychology

Planning Fallacy

We systematically underestimate how long tasks will take, even when we have direct experience of past overruns.

Foundation Psychology

Power Laws

In many systems, a small number of inputs produce the vast majority of outputs. Distributions are rarely equal.

Intermediate Mathematics

Prisoner's Dilemma

When two parties would both benefit from cooperating but each has an individual incentive to defect, the result is often mutual loss.

Intermediate Economics
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Process vs Outcome Thinking

Judge decisions by the quality of the reasoning, not the quality of the result. Good processes sometimes produce bad outcomes, and vice versa.

Foundation General Thinking
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Removal as Strategy

Sometimes the best move isn't adding something new — it's removing something that's holding you back.

Foundation General Thinking

Satisficing vs Maximising

Choose the first option that meets your criteria rather than exhaustively searching for the best possible option.

Foundation Psychology
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Scenario Planning

Imagine multiple futures, not just one. Prepare for several plausible outcomes rather than betting everything on a single prediction.

Intermediate General Thinking

Scope Insensitivity

We fail to scale our emotional response proportionally. Saving 200,000 birds doesn't feel 100x more important than saving 2,000.

Intermediate Psychology

Signal vs Noise

Most information is noise. The skill is filtering for the signal — the rare data points that actually change your understanding.

Intermediate Mathematics
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Specialisation vs Generalisation

Specialists exploit narrow advantages efficiently. Generalists adapt to change flexibly. The optimal strategy depends on environmental stability.

Intermediate Biology

Status Quo Bias

We prefer the current state of affairs simply because it's familiar — even when alternatives are objectively better.

Foundation Psychology
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Systems vs Goals

Goals are about the end state you want to reach. Systems are about the process you follow every day. Systems-oriented people tend to outperform goal-oriented people.

Foundation General Thinking

The Lindy Effect

The longer something has survived, the longer it's likely to continue surviving. Age is a positive signal for ideas and systems.

Intermediate Systems Thinking
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Unknown Unknowns

There are things you know you don't know (known unknowns) and things you don't even know you don't know (unknown unknowns). The second category is where the real danger lives.

Intermediate General Thinking

Via Positiva vs Via Negativa

Improvement by subtraction (removing what's harmful) is often more reliable than improvement by addition (adding what's beneficial).

Intermediate General Thinking

Winner's Curse

In competitive bidding, the winner often overpays because winning means you valued the item more than everyone else — likely too much.

Intermediate Economics
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Zero-Sum vs Positive-Sum

Some situations have a fixed pie where one person's gain is another's loss. Many situations have an expandable pie where everyone can gain.

Foundation Economics