July 13, 2019
90+ Useful Mental Models, Frameworks, and Concepts
Mental models can help us understand the world and make better decisions. I’m collecting a list (in no particular order) of the ones I find most helpful and use most frequently. The ones in bold are ones I find particularly useful or impactful.
This list is not exhaustive — it just contains the ones most salient to me. For more mental models, see this awesome list by Farnam Street.
Science
- The scientific method
- Randomized Controlled Trials (RCTs)
- Occam’s razor
- Falsifiability
- Correlation vs causation
- Confirmation bias
- If something claims to fix everything, it probably fixes nothing
Game Theory
- Prisoner’s Dilemma (competitive games)
- Stag Hunt (cooperative games)
- Nash equilibrium
- Coordination failure
- Common knowledge
Economics
- Expected value
- Efficient markets
- Market failures (including information asymmetry, externalities, tragedy of the commons, tyranny of small decisions)
- Diminishing returns
- Zero sum vs non-zero sum
- Mechanism design and incentives
- Trade-offs
- Economies of scale
- Marginal utility
- Network effects
- Opportunity cost
- Option value
- Compounding (related to positive feedback loops)
- Gresham’s Law: Bad money drives out good
- Private vs collective ownership, free markets vs planned economies
- Sustainable Competitive Advantage (structural factors that allow a firm to outcompete its rivals for many years)
- Pareto optimality
- Comparative advantage
- Value of my time
- Value of Information
Statistics
- Survivorship bias
- Regression to the mean
- Probability distributions (in particular: Long-tailed, Fat-tailed, normal, lognormal, power law, bimodal)
- Simpson’s paradox
Systems
- Leverage points
- Unintended consequences (Second-order thinking, Goodhart’s Law, perverse incentives, cobra effect)
- Bottlenecks
- Feedback loops
- Catalysts / activation energy
- Inertia / status quo
- Leaky abstraction (a term from software engineering, but can be applied in other areas, for example, a company that leaks its internal structure to its customers)
- Local vs global optima (terms from Math/CS that apply more broadly, for example: a nice city center apartment might be an accommodation local optimum for you if you live in a city, but it may not be a global optimum if you would be better off in the countryside).
Beliefs and Epistemics
- Bayesian updating
- The map is not the territory
- All models are wrong but some models are useful
- Ideological Turing tests
- Straw man and steel man
- Confidence intervals / calibration training / making predictions
- Foxes vs hedgehogs
- Sequence vs cluster thinking
- For all my beliefs, asking myself: “What would change my mind?”
- Double crux
- Fermi estimates
- Epistemic modesty
Ethics
- Effective Altruism
- Importance, Neglectedness, Tractability
- Thought experiments
- Veil of ignorance
- Utilitarianism
Nature
Politics
- Overton window
- Voting systems and social choice theory (including Arrow’s Impossibility Theorem)
- Unilateralist’s curse
- Institutionalized discrimination and axes of oppression
- Values disagreements vs empirical disagreements
Productivity and Work
- 80/20 rule (AKA the Pareto principle)
- Generalists, specialists, t-shaped people, m-shaped people, temporary specialists
- Deliberate practice
- Maker’s vs manager’s schedule
- Sludge and bureaucracy
- “Everything should be made as simple as possible, but no simpler.” — Albert Einstein
- Optimizing vs satisficing: Sometimes it’s necessary to spend time/resources to achieve the best possible outcome. Other times it’s best to settle for a satisfactory outcome (even if it’s not the best) because it’s not worth the extra time/resources.
- Goal factoring
- “I’m sorry I wrote you such a long letter; I didn’t have time to write a short one” (Writing short and clear things is harder than writing long things)
- Commander’s intent
- Maslow’s hammer: If all you have is a hammer, everything looks like a nail
- “Management is doing things right; leadership is doing the right things” — Peter Drucker
- If everything is a priority, nothing is a priority
Planning
- Murphy’s Law: Anything that can go wrong will go wrong
- Hofstadter’s Law: It always takes longer than you expect, even when you take into account Hofstadter’s Law (related: the Planning Fallacy)
- Parkinson’s Law: Work expands so as to fill the time available for its completion
- “Plans are useless but planning is essential” — Dwight D. Eisenhower
- Gate’s Law: Most people overestimate what they can do in one year and underestimate what they can do in ten years
- Known knowns, known unknowns, unknown unknowns
Psychology
- System 1 and System 2
- Big Five personality traits (The only personality model backed by science)
- FOMO (Fear of Missing Out)
- Hanlon’s Razor: Never attribute to malice that which is adequately explained by stupidity
- Signalling
- Hawthorne Effect
- Imposter Syndrome and the Dunning-Krueger effect
- The sunk cost fallacy
- Cognitive biases
- Chunking (for learning)
- Learned helplessness