All 1045 mental models — searchable and filterable, every page open and free.
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100 People Love
something 100 people love rather than something 1 million people kind of like. Intensity of need
7 Powers Hamilton Helmer
r)Hamilton HelmerThe seven — and only seven — sources of durable competitive advantage: Scale Ec
BATNARoger Fisher
/ William UryBest Alternative to a Negotiated Agreement — your power in any negotiation comes no
Competition is for Losers
thesis: every moment spent competing is a moment not spent building something unique. The goal i
Disagree and Commit
a decision is made after genuine debate, everyone — including dissenters — commits fully to exec
Disruptive Innovation
products in niche markets that improve until they overtake incumbents.
Distribution
products reach customers matters more than the product itself.
Lollapalooza Effects
multiple cognitive biases or forces act in the same direction simultaneously, the combined effec
Do Things That Don't Scale
best startups are built through unscalable, hands-on work first.
Extreme Ownership
own everything in their world — no excuses, no blaming subordinates.
Forcing Function
deliberately introduced to compel desired behaviour.
Founder-Market Fit
founder's unique fit to the problem determines startup success more than any other factor.
Growth vs Fixed Mindset
develop through effort and learning, not innate talent alone.
Availability Heuristic
judge the likelihood of events based on how easily examples come to mind, not on actual frequenc
Hook Model
four-phase cycle that builds habitual product usage.
Innovator's Dilemma
management is the reason great companies fail when disruption arrives.
Iteration Velocity
team that learns fastest wins — speed of iteration is the ultimate advantage.
Jobs to Be Done
hire products to accomplish specific functional, emotional, and social jobs.
Luck Surface Area
/ Naval RavikantIncrease exposure to serendipity by doing more and telling more people.
MVPFrank Robinson
/ Steve Blank / Eric RiesThe smallest thing that tests your riskiest assumption.
Moats
competitive advantages that protect long-term profitability from competitive erosion.
Asymmetric Payoffs
situations where the upside is uncapped and the downside is limited. The expected value of a dec
Network Effects
increases with each additional user, creating exponential competitive advantage.
Platform Business Model
/ Marshall Van AlstyneConnect distinct user groups and create value through network orchestratio
Porter's 5 Forces
industries print money. Others burn it. The difference is rarely about the talent inside the com
Product/Market Fit
customers buy faster than you can build — the only thing that matters.
Red Queen Effect
have to run as fast as you can just to stay in the same place. In competitive environments, stan
Asymmetric Risk
all risks are equal. Some decisions carry small downside with enormous upside; others carry cata
Pygmalion Effect
expectations create high performance through self-fulfilling prophecy.
Positioning
TroutWhere you compete matters more than how hard you compete. Choosing the right strategic posi
Radical Candor
personally and challenge directly — feedback that builds trust and drives improvement.
Reversible vs Irreversible Decisions
doors demand deliberation. Two-way doors demand speed.
Choosing Important Problems
most important decision in any career or research agenda is which problems to work on. Working h
Simplify
is the ultimate sophistication and competitive advantage.
Start With Why
purpose before product — people buy why you do it, not what you do.
Strategy vs Tactics
decides where to play. Tactics decide how to execute.
Sustainable Competitive Advantage
that persist because competitors cannot easily replicate them.
Switching Costs
higher the cost of leaving, the stronger the moat.
Two Pizza Rule
autonomous teams outperform large ones — keep teams feedable by two pizzas.
Viral Marketing
each user brings more than one new user, growth becomes exponential.
Zero to One
something new rather than copying what exists — aim for monopoly, not competition.
Abstraction
complexity behind simpler interfaces to reason at higher levels.
Explore-exploit Tradeoff
gathering new information against leveraging what you already know.
Metcalfe's Law
value grows proportionally to the square of connected users.
Moore's Law
counts double every two years, driving exponential computing gains.
Mythical Man Month
people to a late project makes it later.
Technical Debt
decisions create compounding costs that must be repaid.
Barriers to Entry
obstacles preventing new competitors from entering a market.
Collective Action Problem
incentives to free-ride undermine cooperation for shared benefit.
Comparative Advantage
where your opportunity cost is lowest, not where you are best.
Creative Destruction
destroys established industries to create new, more valuable ones.
Economies of Scale
scale drives lower unit costs, creating compounding cost advantages.
First-Mover
first creates switching costs and brand recognition but bears exploration risk.
Game Theory
von Neumann / Oskar MorgensternStrategic interaction where outcomes depend on all participants c
Increasing Returns
advantages compound through positive feedback into winner-take-most outcomes.
Information Asymmetry
information between parties creates adverse selection and moral hazard.
Jevons Paradox
improvements increase total consumption rather than reducing it.
Moral Hazard
from consequences encourages excessive risk-taking.
Nash Equilibrium
player can improve by unilaterally changing strategy.
Opportunity Cost
édéric BastiatThe true cost of any decision is what you gave up to get it.
Prisoner's Dilemma
TuckerIndividual self-interest produces worse outcomes than cooperation.
Skin in the Game
must bear consequences to align incentives.
Supply and Demand
adjust to balance what producers supply and consumers buy.
The Agency Problem
MecklingAgents with different incentives make suboptimal decisions for principals.
Tragedy of the Commons
self-interest depletes shared resources, harming everyone.
Winner Take All Market
advantages lead to disproportionate concentration of rewards.
Barbell Strategy
at extremes of safety and risk, avoid the mediocre middle.
Circle of Competence
have an edge in some domains and not others — and the boundary between the two is where most cat
Discounted Cash Flow
equals future cash flows discounted to present value.
Margin of Safety
below intrinsic value to protect against errors and the unforeseen.
5 Whys
why five times to find the systemic root cause.
All Models Are Wrong
model simplifies reality; the question is whether it is useful.
Amara's Law
technology short-term, underestimate it long-term.
Eisenhower Decision Matrix
tasks by urgency and importance to focus on what truly matters.
First Principles Thinking
a problem to its fundamental truths and reason up from there — the antidote to reasoning by anal
Goodhart's Law
a measure becomes a target, it ceases to be a good measure.
Law of Triviality
spend disproportionate time on trivial issues they understand.
Map vs Territory
are not reality; confusing the two leads to systematic errors.
Occam's Razor
competing explanations, prefer the simplest one.
Paradigm Shift
old framework is replaced by an entirely new way of seeing.
Parkinson's Law
expands to fill the time available for its completion.
Principle of Falsification
claim is only useful if it can be proven wrong.
Regret Minimization Framework
by asking which choice you would regret least at age 80.
Scientific Method
, hypothesis, experiment, and revision produce reliable knowledge.
Second-Order Thinking
past the immediate effect to the second and third-order consequences.
Deep Work
concentration on demanding tasks produces disproportionate value.
Deliberate Practice
practice targeting specific weaknesses drives elite performance.
Flow State
consciousness where challenge and skill match produces peak performance.
Spaced Repetition
at expanding intervals to beat the forgetting curve.
Bayes Theorem
your beliefs proportionally to how surprising the new evidence is — the foundation of rational i
Black Swan Theory
, unpredictable events with extreme impact shape history.
Compounding
growth from consistent small gains over long time horizons.
Correlation vs Causation
together does not mean one causes the other.
Ergodicity
works across many simultaneously may not work for one across time.
Exponential Growth
accelerates proportionally to current size, slow then explosive.
Fermi Problem
impossible questions into tractable sub-problems for useful estimates.
Global & Local Maxima
best nearby outcome may trap you from reaching the best possible outcome.
Inversion
backwards: instead of asking how to succeed, ask what guarantees failure — then avoid it.
Kelly Criterion
bet sizing maximizes long-term wealth growth while avoiding ruin.
Nonlinearity
not proportional to inputs; small changes can produce massive effects.
Power Law Distribution
small number of items account for a disproportionate share of outcomes.
Probabilistic Thinking
binary judgments with probability estimates under uncertainty.
Probability Theory
mathematical framework for quantifying uncertainty.
Regression to the Mean
outcomes are followed by more moderate ones as luck fades.
Signal vs Noise
meaningful information from irrelevant data.
Asymmetric Warfare
ín-ToftWeaker forces use unconventional tactics to neutralize stronger opponents.
Blitzkrieg
rapid attack at the point of greatest vulnerability.
Fabian Strategy
decisive battle to exhaust a stronger opponent through patience.
Fog of War
von ClausewitzIncomplete information makes reality impossible to see clearly in real time.
Mission Command
intent and objectives; leave tactical execution to those closest.
Mutually Assured Destruction
sides can inflict unacceptable damage, making conflict irrational.
OODA Loop
through observe-orient-decide-act faster than competitors.
Red Team
adversarial challenge from the opponents perspective.
Scorched Earth
resources to deny them to an advancing adversary.
Trojan Horse
offensive capability inside something targets willingly accept.
Adaptation & Red Queen Effect
adaptation is required just to maintain relative position.
Complex Adaptive Systems
interacting agents self-organise to produce emergent behaviour.
Critical Mass
tipping-point threshold where a process becomes self-sustaining.
Entropy
ordered systems tend toward disorder unless energy is continuously invested.
Flywheel
momentum built through consistent effort in one direction.
Incentives
respond to rewards and punishments, not instructions.
Inertia
resist change proportional to their accumulated mass.
Laws of Thermodynamics
transforms but never appears from nothing — every conversion has a cost.
Leverage Archimedes
rchimedesA small force at the right point moves disproportionately large loads.
Momentum
times velocity — once moving fast and heavy, nearly impossible to stop.
Natural Selection & Extinction
belongs to the fit, not the strong — adapt or face extinction.
Newton's Laws
laws of motion governing force, mass, acceleration, and reaction.
Path Dependence
decisions constrain all future possibilities — history matters.
Systems Thinking
interconnections and feedback loops, not isolated components.
Thermodynamics
system has an energy budget — ignore the metabolic cost and it dies.
Stoicism
of Citium / Epictetus / Seneca / Marcus AureliusFocus on what you control, accept what you canno
The Socratic Method
questioning to expose assumptions and clarify thinking.
Thucydides Trap
power vs ruling power — structural stress makes conflict the default.
Anchoring
information encountered disproportionately shapes all subsequent judgements.
Bandwagon Effect
adopt trends because others have — popularity self-reinforces.
Bystander Effect
éMore witnesses means less action — responsibility diffuses across groups.
Cognitive Dissonance
between beliefs and actions drive rationalisation over change.
Confirmation Bias
seek evidence that confirms what we already believe and filter out what contradicts it.
Curse of Knowledge
WeberKnowing something makes it impossible to imagine not knowing it.
Decision Fatigue
quality deteriorates after sustained choices — willpower is finite.
Dunning-Kruger Effect
competence breeds overconfidence; expertise breeds doubt.
Endowment Effect
inflates perceived worth beyond objective value.
Framing Effect
you frame the question determines the answer you get.
Fundamental Attribution Error
blame character when circumstances are the real cause.
Groupthink
groups suppress dissent and converge on flawed decisions.
Halo Effect
positive trait colours evaluation of everything else.
Hindsight Bias
the fact, people believe they knew it all along.
IKEA Effect
ArielyLabour invested inflates perceived worth regardless of quality.
Incentive-Caused Bias
me the incentive and I will show you the outcome.
Lollapalooza
biases combining in the same direction produce extreme outcomes.
Loss Aversion
hurt roughly twice as much as equivalent gains feel good.
Narrative Fallacy
compress complex reality into clean stories, mistaking explanation for prediction.
Peak-End Rule
are judged by their peak moment and their ending.
Planning Fallacy
systematically underestimate time, cost, and risk of projects.
Self-Fulfilling Prophecies
alter behaviour in ways that make the belief come true.
Social Proof
uncertain, people copy what others are doing.
Status Quo Bias
aversion applied to change makes inaction the default choice.
Sunk Cost Fallacy
investments should not drive future decisions.
Survivorship Bias
only survivors produces systematically wrong conclusions.
Antifragility
systems gain from disorder — growing stronger from shocks.
Emergence
wholes arise from simple parts interacting — the whole exceeds the sum.
Feedback Loops
feed back as inputs, creating either amplifying or stabilizing dynamics.
Gall's Law
complex systems evolve from working simple systems.
Leverage Donella Meadows
a MeadowsSmall shifts at the right point produce outsized systemic changes.
Margin of Safety Redundancy and slack
and slack let systems absorb unexpected shocks.
Resilience
that absorb disturbance and reorganise while maintaining function.
Second-Order Effects
of consequences often dominate the intended outcome.
Stock and Flow
accumulate, flows change them — stocks determine behaviour.
Theory of Constraints
one constraint matters — optimising anything else is an illusion.
10x Individuals/Teams
/ Robert CringelyIn 1968, Sackman, Erikson, and Grant published a study in Communications of the
12 Standard Forms of Value
business that has ever generated revenue — from a lemonade stand in Phoenix to a $3 trillion com
5 Parts of Every Business
2005, Spanx had one employee, one product, and $10 million in annual revenue. Sara Blakely was c
A/B Testing
A/B testing is controlled experimentation applied to product and business decisions. Show half y
AARRRDave Mc
stood on a stage in Seattle in 2007 — an Ignite talk, five minutes, twenty slides that auto-adva
Ability to Raise Prices
sat in front of the Financial Crisis Inquiry Commission in 2010 and reduced decades of investmen
Abundance vs Scarcity Mindset
BezosStephen Covey drew the line in 1989. In The 7 Habits of Highly Effective People, he describ
Active Listening
1957, psychologists Carl Rogers and Richard Farson published a short monograph titled Active Lis
Addressability
pitch deck has a TAM slide. Total Addressable Market — that big, round number in the top-right c
Agile
Sutherland / Alistair Cockburn / Martin FowlerIn February 2001, seventeen software developers ga
Amazon Narratives
2004, Jeff Bezos sent an email to his senior team banning PowerPoint from Amazon. The replacemen
Attribution Theory
1958, Austrian psychologist Fritz Heider published The Psychology of Interpersonal Relations and
Bait and Switch
airline runs the same play. The fare is $49. By the time you've selected a seat, checked a bag,
Barrier to Competition
strategists know about barriers to entry — the obstacles that prevent new players from entering
Brand
is not a logo. It is not a colour palette, a tagline, or a mission statement printed on a confer
Bullseye Framework
had a problem. He had built DuckDuckGo — a search engine that competed with Google on privacy —
Bundling and Unbundling
, the CEO who navigated Netscape through the browser wars, told his board something that most bu
Business Case
A business case is a structured argument for why a proposed initiative deserves resources — time
CRMCRM — Customer Relationship Management —
is not software. It is the systematic practice of capturing, organising, and leveraging every in
Capital Allocation Options
dollar a business generates faces the same six-way fork: reinvest in existing operations, acquir
Commandos vs Infantry vs Police
buried one of the sharpest organizational insights of the twentieth century inside a book about
Common Ground
1981, Roger Fisher and William Ury published Getting to Yes: Negotiating Agreement Without Givin
Confidence: Speed vs Quality
his 2016 letter to shareholders, Jeff Bezos made an observation that should be pinned to the wal
Consequence vs Conviction
drew a 2×2 matrix on a whiteboard at an Amazon all-hands meeting in the early 2010s and changed
Core Competency
1990, C.K. Prahalad and Gary Hamel published "The Core Competence of the Corporation" in Harvard
Costly Signalling Theory
1975, Israeli biologist Amotz Zahavi proposed an idea that turned evolutionary theory sideways.
Dark Patterns
2022, the Federal Trade Commission filed a complaint alleging that Amazon had spent years design
Diffusion of Responsibility
éIn a room of twelve executives, a critical metric is flashing red on the dashboard. Every one o
Directly Responsible Individual
morning at Apple, the executive team files into a conference room for a three-hour meeting. The
Disconfirming Evidence
kept a special notebook. Not the famous ones cataloguing finch beaks and barnacle anatomy — a di
Economically Valuable Skills
published "So Good They Can't Ignore You" in 2012 and dismantled the most popular career advice
Expert Problem
spent twenty years tracking 28,000 predictions made by 284 experts — political scientists, econo
FOMO Components
2021, GameStop stock rose from $17 to $483 in three weeks. The fundamental value of a struggling
FUDFear, Uncertainty, and Doubt — FUD
— is the competitive strategy of spreading negative, vague, or misleading information about a ri
Feedback
leader knows they should give more feedback. Almost none of them do. The gap between knowing and
Field Testing
groups loved New Coke. Two hundred thousand blind taste tests confirmed that consumers preferred
Five Fits Framework
companies do not have a bad strategy. They have five disconnected strategies. The product team h
Float
is other people's money that sits in your account before you have to pass it on — and the return
Fostering Culture
is not a mission statement on the wall, a set of values on the careers page, or a foosball table
Founder's Syndrome
trait that makes someone a great founder — pathological conviction, breakneck speed, centralised
Framing Tversky & Kahneman
& KahnemanHow you present information shapes decisions more than the information itself. This is
Free
BrinFree is not the absence of a business model. It is a business model — and in digital markets
Freemium
the product away for free. Charge for the better version. Venture capitalist Fred Wilson named t
Freeroll
A freeroll is a bet where you cannot lose but might win. The downside is zero or negligible. The
Gallup Q12Gallup spent thirty years and
2.7 million employees trying to answer one question: what separates the best workplaces from the
Gamification
the mechanics that make games compulsive — points, levels, badges, leaderboards, progress bars,
Generalist vs Specialist
EpsteinTwo books, published twenty years apart, frame the central tension of human performance.
Heat-seeking Missiles
— co-founder of Benchmark Capital and founding CEO of Wealthfront — distilled a pattern he obser
High-context vs Low-context
1976, anthropologist Edward T. Hall published Beyond Culture, introducing a framework that divid
Horizons Framework
WhiteEvery company is running three businesses at once — whether it knows it or not. Horizon 1 i
Hunting Elephants vs Flies
published a blog post in 2014 that became one of the most referenced frameworks in SaaS investin
Hype Curve
1995, Jackie Fenn — an analyst at Gartner — published a research note that introduced a visual f
Idea Maze
2013, Balaji Srinivasan introduced a concept during Stanford's Startup Engineering course that s
Improving Returns
business models suffer from diminishing returns. The first million dollars in revenue is cheap t
Intellectual Property
property — patents, trademarks, trade secrets, and copyrights — is the legal architecture that t
Iron Law of Market
said it plainly in 2007: "The #1 company-killer is lack of market." Not lack of talent. Not lack
Key Failure Indicator
company tracks KPIs. Revenue growth, customer acquisition cost, net promoter score, monthly acti
Law of Shitty Click Through Rates
2012, Andrew Chen published an essay that named something every growth team already felt in thei
Linear Commerce
2018, Web Smith — founder of 2PM Inc. and one of the sharpest voices in digital commerce analysi
Listen Decide Communicate
sequence is the model. Listen. Decide. Communicate. Three verbs, fixed order, no substitutions.
Loss Leader Strategy
sells its rotisserie chicken for $4.99. It has held that price since 2009 despite poultry costs
Marginal Gains
2003, Dave Brailsford took over as performance director of British Cycling. The programme was, b
Meta-cognition: IQ vs EQDaniel Goleman
/ Peter Salovey / John Mayer / David McClelland / Richard BoyatzisIn 1995, Daniel Goleman publis
Mind Share
share is the percentage of consumer awareness or recall that a brand owns within its category. W
Modularity
called it the Law of Conservation of Attractive Profits: when one layer in a value chain becomes
Narrative
are how humans compress complexity into meaning. A narrative is not decoration layered on top of
Nudge Theory
nudge is any element of choice architecture that alters people's behaviour in a predictable way
Only Paranoid Survive
1985, Andy Grove was losing. Intel — the company he had co-founded — was haemorrhaging money in
Open vs Closed Platform
1981, IBM made a decision that would define the personal computer industry for four decades. Und
Organisational Debt
coined the term in a 2015 blog post, and the framing was deliberately borrowed from engineering:
Perceived Value
hospital charges $5 for an aspirin tablet. The factory that manufactured it sold the same tablet
Peter Principle
1969, Laurence J. Peter published a book that read like satire but operated as diagnosis. The Pe
Pivot
defined it precisely in The Lean Startup (2011): a pivot is a structured course correction desig
Point of Market Entry
you enter a market determines your entire strategic trajectory. Not what you build. Not how well
Premature Optimisation
1974, Donald Knuth published "Structured Programming with go to Statements" in Computing Surveys
Racecar Growth Framework
spent seven years at Airbnb — the last four leading growth for the supply side of the marketplac
Remarkability
published Purple Cow in 2003 with an argument that felt like provocation and turned out to be pr
Repeatable Systems
is not in the food business. It is in the systems business. Ray Kroc did not invent the hamburge
Schlep Blindness
2012, Paul Graham published a short essay that named something every experienced startup investo
Seek Feedback Not Consensus
distinction is surgical. Feedback is information. Consensus is permission. A leader who seeks fe
Segmentation
all customers are equal. The sentence sounds obvious — but most companies operate as though it i
Servant Leadership
1970, Robert Greenleaf — a retired AT&T executive — published an essay called "The Servant as Le
Shadow Testing
1999, Nick Swinmurn walked into shoe stores in the San Francisco Bay Area, photographed pairs of
Six Sigma
1986, an engineer at Motorola named Bill Smith had a problem. Motorola's pagers and mobile phone
Solve Whole Customer Experience
did not build the best computer. He built the best experience of owning a computer. The distinct
Span of Control
many people can one manager actually manage? The question sounds administrative. It is architect
Strategy Tax
company has strategic commitments — the core business model, the platform it protects, the reven
T-Shaped Employees
, CEO of IDEO, gave the concept its clearest articulation in a 2005 essay for Design Management
Team of Teams
2003, General Stanley McChrystal took command of the Joint Special Operations Command in Iraq an
The Third Story
HeenIn 1999, Douglas Stone, Bruce Patton, and Sheila Heen — members of the Harvard Negotiation P
Three Dimensions of Negotiation
people think negotiation is what happens at the table. Two sides, a room, a set of demands, a se
Time Horizon
length of time over which you evaluate a decision changes which decision is rational. Not which
Time Value of Shipping
, VP of Product at Shopify, articulated a principle that experienced operators know intuitively
Trust
The Speed of Trust distilled an observation that every operator knows but few quantify: trust is
Unicorn Candidate
JobsStripe's internal hiring bar, as Patrick Collison has described it repeatedly, reduces to a
Unknown Unknowns
12, 2002, Donald Rumsfeld stood at a Department of Defense press briefing and delivered a senten
Value Chain Analysis
company is not one thing. It is a sequence of activities, each of which adds some portion of the
Value Stream
1950, a Toyota engineer named Taiichi Ohno walked the factory floor and asked a question that wo
Vanity Metrics
2011, Eric Ries published "The Lean Startup" and introduced a term that should have killed the s
Visualization
MinardEdward Tufte's central principle is deceptively simple: the best way to understand complex
Win-Win
and William Ury published Getting to Yes in 1981 and changed how the world negotiates. The book'
Wisdom of Crowd
1906, Francis Galton attended a livestock fair in Plymouth where 787 people paid sixpence each t
Black Box
A black box is a system whose internal workings are hidden or irrelevant: you observe inputs and
Clarke's Third Law
third law: "Any sufficiently advanced technology is indistinguishable from magic." The line appe
Constraint Relaxation
relaxation is a problem-solving move: temporarily drop or loosen a constraint to make a hard pro
Design Pattern
design pattern is a reusable solution to a recurring problem in a context. The term was populari
Divide and Conquer
and conquer is a strategy: break a problem into smaller subproblems of the same kind, solve them
Exponential Backoff
backoff is a retry strategy: after a failure, wait before retrying, and increase the wait each t
Filter Bubble
filter bubble is an information environment shaped by algorithms (and choices) so that you see m
Information Cascade
information cascade occurs when people abandon their private signal and copy the observed action
Look-Then-Leap Rule
look-then-leap rule is an optimal stopping strategy: spend a defined phase gathering information
Mechanism Design
MyersonMechanism design is the reverse of game theory: instead of analysing the outcome of given
Moravec's Paradox
paradox is the observation that the hard problems for humans are often easy for machines, and th
Parallel Processing
processing is doing multiple units of work at the same time instead of one after the other. In c
Recursion
is when a process or structure is defined in terms of itself: a function calls itself, a structu
Adverse Selection
1970, George Akerlof published "The Market for Lemons," a thirteen-page paper that nearly didn't
Bertrand Paradox
1883, the French mathematician Joseph Bertrand reviewed Antoine Augustin Cournot's work on duopo
Bottlenecks
1984, an Israeli physicist named Eliyahu Goldratt published a business novel called The Goal. Th
Coase Theorem
1937, a 27-year-old British economist named Ronald Coase asked a question that no one in his pro
Common Knowledge
Christian Andersen's "The Emperor's New Clothes," every citizen privately knows the emperor is n
Competitive Destruction
once observed that the airline industry has destroyed more shareholder value than it has created
Complements & Substitutes
products are complements when consuming more of one increases demand for the other. They are sub
Conspicuous Consumption
coined the term "conspicuous consumption" in The Theory of the Leisure Class (1899) to describe
Counterfactuals
A counterfactual is a "what if" — a scenario that did not happen but could have. "If Kennedy had
Deadweight Loss
loss is the value that disappears when a market is distorted — the trades that would have happen
Diminishing Utility
first unit of something you consume gives you more satisfaction than the second. The second give
Division of Labour
opened The Wealth of Nations (1776) with a pin factory. One worker making pins from start to fin
Economic Rent
rent is income above opportunity cost. David Ricardo defined it in 1817: farmers pay for land's
Elasticity
responsive is quantity to price? Price elasticity of demand answers that question with a single
Evolutionarily Stable Strategy
introduced the concept in 1973: a strategy that, once adopted by a population, cannot be invaded
Expected Utility Theory
and Morgenstern (1944) formalised rational choice under uncertainty: maximise expected utility,
Free-rider Problem
a benefit is shared and your contribution is hard to observe, the rational move is to contribute
Gresham's Law
two forms of money are legally required to be accepted at the same face value but have different
Income & Substitution Effects
a price changes, demand doesn't just move — it splits. The substitution effect is the shift betw
Keynesian Beauty Contest
Theory (1936), John Maynard Keynes described a newspaper contest: readers pick the six prettiest
Law of Diminishing Returns
more of one input, while holding others fixed, eventually yields smaller and smaller increments
Marginal Cost/Benefit
are made at the margin. The question is never "should we do this at all?" in the abstract — it i
Market Power
power is the ability to set price above marginal cost without losing so much volume that the mov
Market for Lemons Problem
sellers know more about quality than buyers, and buyers can't tell good from bad before purchase
Matthew Effect
rich get richer; the poor get poorer. Success breeds success; failure compounds. The name comes
Perfect Competition
competition is a benchmark: many buyers and sellers, identical products, free entry and exit, fu
Positive & Negative Externalities
externality is a cost or benefit that falls on parties outside a transaction. The buyer and sell
Price Discrimination
discrimination is charging different prices to different customers for the same or similar produ
Public Goods
public good is non-rival and non-excludable. Non-rival: your consumption does not reduce mine. N
Ratchet Effect
A ratchet only turns one way. In economics, the ratchet effect is the tendency for levels of eff
Rent-Seeking
is the use of resources to capture existing value rather than to create new value. Instead of pr
Resource Curse
rich in oil, minerals, or other extractive resources often grow slower, suffer more corruption,
Scarcity Scarcity is the condition that
dition that human wants exceed the means to satisfy them. Not everything can be had in unlimited
Social vs Market Norms
operate in two kinds of exchange: social norms and market norms. Social norms are gift-based, re
Specialization
is the allocation of resources — labour, capital, attention — to a narrow set of activities wher
Spillover Effects
effects are costs or benefits that flow from one activity or decision to parties who are not dir
Sunk Costs Sunk costs are past
ts are past expenditures of time, money, or effort that cannot be recovered. In economic logic,
The Experience Curve
time cumulative output doubles, unit cost falls by a predictable percentage. That is the experie
The Invisible Hand
pursuing their own interest can produce collective outcomes that no one intended. Adam Smith cal
Thinking at the Margin
are made at the margin. The relevant question is not "Is this good or bad in total?" but "What h
Tit-for-tat
first. Then do whatever the other player did last. That is tit-for-tat: one round of cooperation
Trade-offs
choice surrenders something. Trade-offs are the structure of that surrender: to gain X you give
Transaction Costs
do not run for free. Every exchange — buying, selling, contracting, coordinating — consumes reso
Tullock Paradox
people compete for a fixed prize, they can spend more in the aggregate than the prize is worth.
Two-sided Market
A two-sided market has two distinct user groups that need each other: buyers and sellers, riders
Ultimatum Game
Güth / Rolf Schmittberger / Bernd SchwarzeOne party proposes how to split a fixed pie. The other
Utility
is the satisfaction or benefit an agent gets from an outcome. It is not directly observable — we
Winner's Curse
a common-value auction, the object has the same value to everyone, but bidders don't know it. Ea
Zero Price Effect
is not just another price. When the price drops from a small positive amount to zero, demand jum
Zero vs Positive-Sum
: one party's gain equals the other's loss. The pie is fixed. Positive-sum: the pie can grow; bo
Arbitrage
is profiting from a price difference for the same or equivalent asset across markets, with no ne
Asymmetric Upside
upside is a payoff structure where the best-case gain is large relative to the worst-case loss.
Cost of Capital
of capital is the minimum return a company or project must earn to justify using investors' mone
Dollar-Cost Averaging
averaging (DCA) is investing a fixed amount of money at regular intervals regardless of price. Y
Financial Ratios
ratios compress a company's financial statements into comparable, interpretable numbers. They an
Hedging
is taking an offsetting position to reduce the risk of an existing exposure. You own something t
Intrinsic vs Market Value
value is what an asset is worth based on its fundamental ability to generate cash flows or utili
Margin Call
A margin call is the broker's demand that you add collateral or close positions when the value o
Mr. Market
is Benjamin Graham's allegory: a manic-depressive partner who shows up every day and offers to b
Option Value
value is the worth of the right — but not the obligation — to do something later. In finance, an
Position Sizing
sizing is how much of your capital you put in any single bet. It's not which assets to hold — it
Risk-Reward Ratio
ratio is the comparison of what you can gain to what you can lose on a bet. If you risk $1 to ma
Time Value of Money
value of money (TVM) is the principle that a dollar today is worth more than a dollar tomorrow.
Too Tough Basket
too-tough basket is the set of decisions or opportunities you explicitly choose not to make — be
Domain Dependence
in one field does not automatically transfer to another. Domain dependence is the tendency to ap
Efficiency vs Effectiveness
is doing things right; effectiveness is doing the right things. The distinction is operational:
Epidemic Models
models describe how something — a pathogen, a behaviour, a product, an idea — spreads through a
False Cause
cause is the error of inferring that A caused B when the evidence supports only that A and B are
False Positives & False Negatives
A test or decision has four outcomes: true positive (correctly say "yes" when the state is yes),
Hanlon's Razor
attribute to malice that which is adequately explained by incompetence or ignorance. Most bad ou
Hofstadter's Law
"It always takes longer than you expect, even when you take into account Hofstadter's Law." Doug
Hypothesis
A hypothesis is a testable claim about the world. Not a wish, not a vision — a proposition that
ICE Framework
is a prioritisation score: Impact × Confidence × Ease. Rate each dimension (e.g. 1–10), multiply
Law of Narrative Gravity
pull. Once a narrative takes hold, it attracts evidence, attention, and belief. Facts that fit t
Lindy Effect
longer something has survived, the longer it's likely to survive. That's the Lindy effect. A boo
Miles's Law
"Where you stand depends on where you sit." Rufus Miles, a federal budget official, said it in t
Minimum Effective Dose
minimum effective dose (MED) is the smallest input that produces the desired outcome. Borrowed f
Motte and Bailey
motte-and-bailey is a rhetorical move: defend an indefensible claim (the bailey) by retreating,
Murphy's Law
— "anything that can go wrong will go wrong" — is a heuristic for risk and design. Treat it as a
Necessity & Sufficiency
and sufficiency are the two ways a condition can relate to an outcome. A condition is necessary
Observer Effect
observer effect is the change in a system caused by the act of observing or measuring it. In phy
Outcome Blind
evaluation is judging a decision by the quality of the process and the information available at
Poliheuristic Decision Theory
decision theory describes how people actually choose when stakes are high: a two-stage process.
Pre-Mortem Analysis
pre-mortem is a decision exercise: assume the project or decision has already failed, then work
Proxy
A proxy is a stand-in: you use one thing to represent another when the thing you care about is h
Punctuated Equilibrium
equilibrium, from evolutionary biology, describes change that is not smooth: long periods of sta
Randomized Controlled Experiment
A randomized controlled experiment (RCT) is the gold standard for learning whether something cau
Replication Crisis
replication crisis is the discovery that many published research findings do not hold when other
Revealed Preference
people say they want and what they actually choose are often different. Revealed preference is t
Steelmanning
is the practice of strengthening an opposing argument before engaging it. Instead of attacking t
Structure of Scientific Revolutions
does not advance by steady accumulation. It advances in fits: long periods of normal science und
Sturgeon's Law
percent of everything is crap. Theodore Sturgeon, the science-fiction writer, said it when defen
Systems vs Goals
are outcomes you want to hit. Systems are the processes you run that make outcomes more likely.
Thinking Gray
gray is the discipline of not choosing a side too early. Instead of deciding quickly whether som
Tight Coupling
coupling means components in a system depend on each other in rigid, time-sensitive ways. When o
Unforced Error
unforced error is a mistake that was not caused by the opponent or by external pressure — you ha
Via Negativa
often comes from subtraction, not addition. Knowing what to remove — bad habits, unnecessary com
Wright's Law
says that the cost of a unit declines by a consistent percentage every time cumulative productio
10,000 Hour Rule
takes time. Malcolm Gladwell popularised the idea in Outliers: roughly 10,000 hours of practice
80/20 Rule Vilfredo Pareto
o ParetoA small share of causes drives a large share of results. The Pareto principle — the 80/2
Active Recall
information from memory strengthens learning more than re-exposing yourself to it. Active recall
Attention Management
is the bottleneck. You can manage time and still lose the day to fragmentation — meetings, notif
Cognitive Load Theory
memory is limited. Cognitive load theory (CLT), developed by John Sweller and others, says that
Compounding Knowledge
can compound. What you learn today makes the next learning easier: new concepts attach to existi
Desirable Difficulty
that feels easy often leaves little trace. When retrieval is effortless and conditions match the
Feedback Loops Learning requires a loop:
es a loop: act, observe the result, compare to intent, adjust. Without feedback — accurate, time
Feynman Technique
you can't explain it simply, you don't understand it well enough. The Feynman Technique turns th
Grit
is persistence toward long-term goals despite setbacks, boredom, and the temptation to quit. Ang
Growth Mindset
mindset is the belief that ability and intelligence can be developed through effort, strategy, a
Habits
habit is a behaviour that has become automatic — triggered by context or cue with minimal consci
Interleaving
is mixing different types of practice or topics within a session instead of blocking — doing one
Mental Representations
representations are the internal structures you use to perceive, understand, and act on the worl
Mindfulness
is the practice of attending to present-moment experience with openness and without automatic ju
Power of Routine
power of routine is the leverage you get from making repeated behaviours automatic, predictable,
Sleep & Recovery
and recovery are the processes that restore cognitive, emotional, and physical capacity after lo
Algorithms
algorithm is a finite, unambiguous sequence of steps that transforms inputs into outputs. No amb
Anti-patterns
anti-pattern is a recurring solution that looks plausible but backfires: it solves a surface pro
Apophenia
is the tendency to perceive meaningful patterns in random or meaningless data. The brain is a pa
Back-of-envelope Calculation
A back-of-envelope calculation is a quick, approximate computation done with minimal tools — nap
Central Limit Theorem
(CLT) says that the distribution of the sum (or average) of many independent random variables te
Conditional Probability
probability is the probability of an event given that another event has occurred: P(A|B) = P(A a
Confounding Factor
A confounding factor (confounder) is a variable that influences both the supposed cause and the
Gambler's Ruin
ruin is the mathematical certainty that a player with finite capital playing against a house (or
Inflection Point
inflection point is the moment when the rate of change itself changes — the curve stops bending
J-Curve
is the shape of outcomes when things get worse before they get better. Performance drops, then r
Law of Large Numbers
law of large numbers says that as you repeat a random experiment more and more times, the averag
Law of Small Numbers
law of small numbers is a cognitive bias: we treat small samples as if they were large. We see p
Long Tail
long tail is the large number of low-volume items that collectively can match or exceed the sale
Major vs Minor Factors
vs minor factors is the discipline of separating what actually moves the outcome from what doesn
Monte Carlo Fallacy
fallacy — also called the gambler's fallacy — is the belief that past independent outcomes chang
Monte Carlo Simulation
ław Ulam / John von NeumannMonte Carlo simulation estimates outcomes by running many random tria
Multiplying by Zero
a chain of multiplicative factors, one zero makes the product zero. Revenue = traffic × conversi
Order of Magnitude
of magnitude is the size of something expressed as a power of ten. Is it 10, 100, 1,000, or 10,0
Outliers
are observations that lie far from the bulk of the data — the extreme values that don't fit the
Queuing Theory
theory is the study of waiting lines: how jobs, requests, or customers arrive, how they are serv
Randomness
is the absence of a deterministic pattern: outcomes that cannot be predicted with certainty from
Reference Class Forecasting
class forecasting answers a single question: when projects like this one were attempted, what ac
Scale
is the relationship between size and outcome: how do cost, performance, or value change as you m
Scenario Analysis
analysis replaces a single forecast with a small set of distinct futures — typically base, upsid
Scope Neglect
neglect is the failure to adjust judgment or willingness to pay when the scale of the problem ch
Sensitivity Analysis
analysis asks: when we change one input, how much does the output change? It identifies which as
Simpson's Paradox
paradox is the reversal of a trend or comparison when data are aggregated versus when they are s
Standard Deviation & Normal Distribution
deviation measures spread: how far outcomes typically are from the average. If the mean is 100 a
Alliances
are formal or informal coalitions formed when the cost of going alone exceeds the cost of sharin
Appeasement
is the strategy of conceding to an adversary's demands in the hope that satisfaction will reduce
Arms Races
arms race is a competitive spiral in which rivals invest in capability to match or exceed each o
Attrition Warfare
warfare is the strategy of winning by exhausting the enemy's resources — men, materiel, morale,
Beachhead
A beachhead is a small, secured position from which to launch a larger advance. In military use,
Brute Force Solution
A brute force solution is one that achieves the objective by applying overwhelming resources rat
Burn the Boats
retreat so advance is the only option. The image comes from legend: a general lands on hostile s
Carrot & Stick
and punishment shape behaviour. The carrot induces compliance by offering gain; the stick enforc
Choke Point
A choke point is a narrow passage through which flow must go. Control it and you control the flo
Cold War
A cold war is sustained rivalry without full-scale hot war. Two or more powers compete for influ
Containment
is the strategy of limiting a rival’s expansion without seeking total victory. You don’t invade
Counterinsurgency
(COIN) is the fight against an insurgency — a weaker party that refuses conventional battle and
Defense in Depth
in depth is the use of multiple, layered barriers so that a single failure doesn't compromise th
Deterrence Effect
is the use of credible threat to persuade an opponent not to act. You do not have to fight if th
Discipline
is the capacity to act in line with your goals and standards despite temptation, fatigue, or sho
Empty Fort Strategy
fort strategy is appearing strong when you are weak: leaving the gates open, the walls undefende
Exit Strategy
strategy is the plan for how you stop: how you withdraw from a position, a commitment, or a conf
Guerilla Warfare
warfare is the strategy of the weaker side: avoid pitched battle, strike where the strong cannot
Intelligence
is the collection, analysis, and use of information to understand an opponent, environment, or s
Lead Domino
lead domino is the one piece that, when tipped, knocks over the rest. In strategy it is the sing
Potemkin Village
village is a façade: something built or staged to look impressive while hiding the lack of subst
Proxy War
A proxy war is a conflict in which two or more major powers compete through surrogates rather th
Shock & Awe
and awe is the strategy of achieving rapid dominance by overwhelming the opponent with speed, sc
Swarming
is coordinated action by many dispersed units that converge on a target or objective without cen
Turning Movement
A turning movement is an attack that avoids the opponent's strength by going around it — not nec
Two-Front War
A two-front war is fighting two separate opponents or commitments at once — and losing the advan
Win Without Fighting
win without fighting is to achieve your objective by making the opponent concede, withdraw, or a
Winning Hearts & Minds
hearts and minds is the strategy of securing lasting support from a population or group by addre
Activation Energy
do not start the instant ingredients touch. They need a minimum energy input — activation energy
Autocatalysis
an autocatalytic reaction, the product of the reaction speeds up the reaction itself. The output
Bullwhip Effect
changes in demand at the consumer end of a supply chain amplify as they move upstream. Retailers
Butterfly Effect
small change in initial conditions can produce a large change in outcome. The metaphor — a butte
Catalysis
A catalyst speeds a reaction without being consumed. It lowers the activation energy — the barri
Center of Gravity
von ClausewitzIn physics, the center of gravity is the point at which an object's mass can be co
Chain Reaction
A chain reaction is a sequence in which each step triggers the next. One event causes another, w
Chaos Theory
theory studies deterministic systems that are nonetheless unpredictable in practice. The equatio
Competition
is the struggle for limited resources. In ecology, species compete for food, space, and mates; t
Cooperation In biology, symbiosis is th
iosis is the living together of different species in a way that affects one or both. Mutualism i
Dunbar's Number
brains can maintain only so many stable social relationships. Robin Dunbar proposed a ceiling: r
Ecosystems
ecosystem is a set of actors that depend on one another for survival and growth. In nature, spec
Equilibrium
is the state where opposing forces balance and the system has no tendency to change unless distu
Exaptation
is the use of a trait or technology for a function other than the one it evolved or was designed
Filling a Vacuum
abhors a vacuum; so do markets and organisations. Where there is unmet demand, unserved need, or
Frame of Reference
and judgments depend on where you stand. In physics, velocity and position are relative to a fra
Friction & Viscosity
resists motion; viscosity is resistance to flow. In physics, friction opposes relative motion be
Half-life
is the time for half of something to decay or disappear. In physics, it describes radioactive is
Hedonic Treadmill
adapt to their circumstances. A raise or a new car boosts happiness for a while, then baseline r
Heisenberg Uncertainty Principle
cannot know both the position and the momentum of a particle with arbitrary precision. The more
Hierarchical Organisation
systems achieve coordination through layered structure: authority, information, and tasks flow a
Homeostasis
that persist do so by staying within viable bounds. Homeostasis is the set of mechanisms that de
Irreversibility
changes cannot be undone. Irreversibility is the property that certain processes run one way: ti
Niches
A niche is a subset of the environment where specific conditions allow a subset of players to su
Reciprocity For every action there is
there is an equal and opposite reaction. Newton's third law is reciprocity in mechanics: forces
Relativity
and judgments depend on the frame from which they're observed. Relativity in physics — Einstein'
Scale & Limits
that work at one size often break or bend at another. Scale and limits is the principle that sys
Signalling & Countersignalling
is the use of observable actions or traits to convey information that would otherwise be hard to
Tendency to Minimize Energy Output
— physical, biological, and organisational — tend toward states that require less energy to main
Velocity
is rate of change with direction — how fast you're moving and where. In physics it's displacemen
Burden of Proof
must prove what? Burden of proof answers that question. The party making a claim bears the oblig
Cargo Cults
the surface without the substance produces ritual, not results. Cargo cults take their name from
Cave of Plato
we take for reality can be shadows on a wall. In Plato's Republic, prisoners are chained in a ca
Chilling Effect
A chilling effect occurs when the threat of legal action, retaliation, or sanction causes people
Consequentialism
right action is the one that produces the best outcome. Consequentialism judges acts (or rules,
Due Process
a decision is made can matter as much as what is decided. Due process is the requirement that de
Effective Altruism
the most good you can with what you have. Effective altruism (EA) applies evidence and reason to
Ethos Pathos Logos
runs on three rails: who you are, what they feel, and what you can prove. Aristotle distinguishe
Golden Rule
— treat others as you would have them treat you — is a reciprocity norm found across traditions:
Good Faith
honestly; don't exploit the letter while violating the spirit. Good faith is the obligation to a
Historic Recurrence
doesn't repeat, but it rhymes. Historic recurrence is the observation that similar patterns — bo
Importance of Geography
shapes outcome. Geography — location, terrain, climate, resources, neighbours — constrains and e
Inclusive Economic & Political Institutions
institutions spread power and opportunity. They enforce property rights for a broad cross-sectio
Nuclear Option
nuclear option is an action so costly or destructive that it is rarely used — but the threat of
Precedents
A precedent is a past decision or outcome that is used to guide or justify a current one. In law
Regulatory Capture
capture occurs when a regulator comes to serve the interests of the industry it oversees rather
Secrets
secret, in Peter Thiel's formulation, is something important that is true but not widely believe
Ship of Theseus
of Theseus is a thought experiment: if you replace every plank of a ship, one by one, is it stil
Shirky Principle
, named after Clay Shirky: "Institutions will try to preserve the problem to which they are the
The Overton Window
window is the range of ideas that are acceptable to discuss in public at a given time. Named aft
The Trolley Experiment
trolley problem is a thought experiment: a runaway trolley will kill five people unless you pull
Utilitarianism
is the view that the right action is the one that produces the greatest total well-being (utilit
Veil of Ignorance
veil of ignorance is a thought experiment from John Rawls: when designing the rules of society (
Attention Residue
2009, Sophie Leroy at the University of Minnesota published a paper that should have restructure
Availability Cascade
1999, Timur Kuran and Cass Sunstein published a paper that explains half of what goes wrong in p
Backfire Effect
2010, Brendan Nyhan and Jason Reifler published a study that broke a fundamental assumption abou
Big Five Personality Traits
1992, Paul Costa and Robert McCrae published the NEO Personality Inventory — Revised, and person
Bounded Rationality
introduced bounded rationality in 1955 and won the Nobel Prize in Economics for it in 1978. The
Chesterton's Fence
: "Don't ever take a fence down until you know the reason it was put up." Before removing a rule
Classical Conditioning
(1890s): a neutral stimulus paired with an unconditioned stimulus becomes a conditioned stimulus
Commitment & Consistency
principle: people want to be consistent with their past commitments. Foot-in-the-door — a small
Conformity
1951, Solomon Asch put seven people in a room and showed them a line on a card. He then showed t
DISC Model
GeierIn 1928, William Marston published Emotions of Normal People, proposing four behavioural st
Delayed Gratification
1970, Walter Mischel sat four-year-olds down at a table at Stanford's Bing Nursery School and pl
Denial
Kübler-RossIn 1975, a 24-year-old Kodak engineer named Steven Sasson built the first digital cam
Ego Depletion
1998, Roy Baumeister ran an experiment that reshaped how psychologists think about self-control.
Embodied Cognition
and Johnson's framework: thought is shaped by the body. We "grasp" ideas, "warm" to people, give
Essentialism
2014, Greg McKeown published Essentialism: The Disciplined Pursuit of Less — a book whose subtit
Gambler's Fallacy
18, 1913, at the Monte Carlo Casino, the roulette wheel landed on black. Then black again. And a
Golem Effect
1968, Robert Rosenthal and Lenore Jacobson ran an experiment at a San Francisco elementary schoo
Hippo Problem
: the tendency to defer to the most senior person in the room, regardless of data. Avinash Kaush
Hyperbolic Discounting
discount future rewards more than exponential discounting predicts. $100 today vs $110 tomorrow
Illusion of Control
1975, Ellen Langer ran a deceptively simple experiment at Yale. She sold lottery tickets to offi
Illusory Truth Effect
ToppinoIn 1977, Lynn Hasher, David Goldstein, and Thomas Toppino ran an experiment that should h
Intrinsic vs Extrinsic Motivation
and Richard Ryan's Self-Determination Theory identifies three innate psychological needs that dr
Intuition
1 is fast, automatic, pattern-based. It does not deliberate. It recognises. Intuition is compres
Irrational Escalation
cost fallacy in action: doubling down on failing projects to justify past investment. Barry Staw
Learned Helplessness
1967, Martin Seligman and Steven Maier ran an experiment at the University of Pennsylvania that
Maslow's Hierarchy
published "A Theory of Human Motivation" in 1943 and proposed five levels of need: physiological
Mental Accounting
(1985): people treat money differently based on where it came from or what it's for. Lottery win
Motivation
is the force that drives behaviour. Victor Vroom's Expectancy Theory (1964) distils it into thre
Neglect of Probability
don't evaluate risk by computing probabilities. They evaluate risk by imagining outcomes. The mo
Nudging
and Sunstein (2008): small changes in choice architecture that alter behaviour without restricti
Overthinking
Bezos / Reed HastingsAnalysis paralysis is excessive rumination that impairs decision-making. Th
Pattern Matching
are pattern-seeking machines. We see faces in clouds, conspiracies in randomness. The brain comp
Placebo Effect
creates physiological change. Sugar pills reduce pain when patients believe they're medicine — n
Priming
to a stimulus influences response to a subsequent stimulus. Bargh's elderly-walking study (1997)
Reactive Devaluation
(1995): proposals are devalued because of who proposed them. The same deal from an adversary is
Risk Compensation
1975, University of Chicago economist Sam Peltzman published a study that infuriated the safety
Scout Mindset
spent a decade studying why some people update their beliefs when confronted with evidence and o
Selective Perception
perceive what we expect or want to see. The same data supports opposing conclusions. Confirmatio
Sensemaking
: how people make sense of ambiguous situations. Sensemaking is retrospective — we understand wh
Seven Deadly Sins
the GreatPride, greed, wrath, envy, sloth, gluttony, lust — Pope Gregory the Great codified thes
Stereotyping
generalized beliefs about a group to individuals. The brain's compression algorithm — efficient
Suggestibility
tendency to accept and act on suggestions from others. Children are highly suggestible; adults l
Tribalism
favouritism and out-group hostility. We evolved in tribes; us vs them is default. The brain does
Variable Reinforcement
put pigeons in boxes and gave them food pellets for pressing a lever. When the pellet came every
Zeigarnik Effect
1927, Bluma Zeigarnik was sitting in a Viennese café with her doctoral adviser, Kurt Lewin, when
Automation
is the use of technology to perform tasks with minimal human intervention. The goal is to increa
Backup System Model
A backup system is a parallel capability that takes over when the primary fails. The model is si
Breakpoints
A breakpoint is a value or condition at which system behaviour changes discontinuously. Below th
Causal Loops Diagrams
loop diagrams (CLDs) map how variables influence each other over time. Each arrow is a causal li
Churn
is the rate at which customers, users, or subscribers leave. It is the outflow in a stock-and-fl
Counterparty Risk
risk is the risk that the other party to a contract, trade, or dependency will not fulfil their
Fail-safes
A fail-safe is a mechanism that defaults to a safe state when something goes wrong. Failure of a
Friction
is resistance to motion or change. In physics it opposes movement; in systems it opposes flow —
Hysteresis
is when the state of a system depends not only on current conditions but on its history. The pat
Interdependence
means that parts of a system depend on each other. Change in one part affects others; those effe
Irreducibility
means the whole cannot be fully explained or predicted from the parts alone. The system has prop
Le Chatelier's Principle
principle says: when a system at equilibrium is disturbed by a change in condition (temperature,
Normal Accidents
accident theory, from Charles Perrow, says that in systems that are both complex (many parts int
Optimization
is improving a system toward a defined objective — making a chosen variable as good as possible
Paradox of Automation
paradox of automation: the more reliable and capable the automated system, the less practice hum
Quality Control
control is the set of activities that ensure output meets a defined standard — detection, measur
Redundancy
is duplicate capacity or parallel paths so that if one element fails, the system can still funct
Refactoring
is changing the internal structure of a system without changing its external behaviour — improvi
Reflexivity
is the two-way causal link between belief or perception and reality: beliefs change behaviour, b
Slack
is spare capacity — time, resources, or optionality — that is not committed to the current plan.
Standard Operating Procedure
A standard operating procedure (SOP) is a documented, repeatable sequence of steps for a defined
Stress Testing
testing is deliberately subjecting a system to extreme or adverse conditions to see how it behav
The Critical Few
critical few are the small number of factors, people, or actions that drive the majority of outc
The Experimental Mindset
experimental mindset is the habit of treating beliefs as hypotheses and the world as testable. I
10 Ways to Evaluate Market
A structured checklist of ten dimensions to assess whether a market is worth entering or scaling
5 W's and 1HWho, What, When,
, Why, and How: six questions that force a complete brief. Applied to any initiative, product, o
Accumulation
compound when small, repeatable gains stack over time — users, data, reputation, capability. Acc
Alternative Dispute Resolution
(mediation, arbitration, negotiation) resolves conflict outside courts. The idea: faster, cheape
Alternatives
choice is made against alternatives — the other options you could take. Thinking in alternatives
Amplification
is using existing reach or mechanisms to multiply the impact of a message, product, or action. O
Attention
is the scarce resource: people have limited focus and time. Winning it means being relevant, sal
BANTBANT is a sales qualification framework:
, Authority, Need, and Timeline. Before investing in a deal, confirm the prospect has money to s
Baker's Dozen
dozen is the practice of giving 13 when 12 is expected — deliberate overdelivery. In business it
Barriers to Purchase
to purchase are anything that blocks or slows a buyer from completing a transaction: friction (s
Basketball Politics
politics is the dynamic where a few people have the ball (information, decisions, access) and ot
Best Content Involves Red Pill"Best content
involves red pill" means the most effective content often challenges what the audience assumes —
Buffer
A buffer is capacity or time held in reserve so the system can absorb variation without failing.
Call to Action
A call to action (CTA) is the explicit instruction that tells the audience what to do next: sign
Channel Evaluation Framework
A channel evaluation framework is a structured way to assess and compare acquisition channels: w
Channel vs Product-led Growth
growth uses sales, partnerships, or paid acquisition to get the product in front of buyers; prod
Compromise Effect
compromise effect is the tendency to prefer a middle option when choices are ordered by some dim
Confirming Conversations
conversations are exchanges that validate what you already believe or want to hear — "yes, that'
Conjoined Triangles of Success
of Success is a satirical framework from Silicon Valley (HBO): two triangles representing "Failu
Contrast Is Drug
is drug: the human brain is wired to notice and remember difference — before vs after, old vs ne
Controversy
is disagreement or provocation that triggers strong reaction — approval or outrage — and often s
Core Human Drives
human drives are the deep motivations that shape behavior: survival, belonging, status, meaning,
Cost
is what you give up to get something — money, time, attention, optionality. In building and scal
Critical Assumptions
assumptions are the beliefs that must hold for your strategy or bet to work — "customers will pa
Customer Buying Journey
customer buying journey is the path from first awareness to purchase and beyond: awareness → con
Customer Hunting Types
hunting types are the different ways you go to market to acquire customers: outbound (you reach
Customer Personas
personas are archetypal descriptions of who you're selling to — a named, concrete profile (e.g.
Damaging Admission
A damaging admission is when you voluntarily surface a weakness, limitation, or failure that the
Demonstration
is showing the product or outcome in action so the prospect sees the result rather than just hea
Desire
is the want that precedes action — the pull toward an outcome, identity, or experience. In busin
Distribution Channel
A distribution channel is the path through which your product or message reaches the customer —
Double Down on Strengths
down on strengths means investing more in what already works and where you’re already strong, in
Duplication
is scaling by replicating a working unit — the same process, format, or model — in new contexts.
Economic Values
values are the forms of value a business can create and capture — not just product for money, bu
Education-Based Selling
selling is leading with useful information and insight so the prospect learns something before y
End Result
result is the outcome you’re building toward — the customer state, the metric, the moment that d
Exclusivity
is the perception that an offer, access, or identity is limited — by invitation, capacity, quali
Expectation Effect
expectation effect is the tendency for expectations — what we believe will happen — to influence
Force Multiplier
A force multiplier is a factor that amplifies the output of a given input — tools, people, proce
Four Pricing Methods
pricing methods frame how you set price: cost-plus (markup on cost), competitive (match or beat
Get Shit Done
shit done (GSD) is the bias toward execution over planning: ship, learn, and fix rather than per
Go-For-It Window
go-for-it window is the period when conditions align to make a bold move — market, team, capital
Hassle Premium
hassle premium is the extra willingness to pay when you remove friction, complexity, or effort f
Incremental Augmentation
augmentation is improving a product, process, or system in small, additive steps rather than big
Institutional Knowledge
knowledge is the collective know-how that lives in people, practices, and context — how things r
Intermediation & Disintermediation
is the insertion of a middle layer between producer and consumer (e.g. distributor, marketplace,
Levels of Awareness
of awareness describe where the prospect is in relation to their problem and your solution: unaw
Loyalists vs Mercenaries
are people (customers, employees, partners) who stay for mission, relationship, or identity; mer
Major Acquisition Lanes
acquisition lanes are the primary channels or motions that bring customers in — paid, organic, r
Managing to Person
report is different — in skill, motivation, and context. Managing to the person means adjusting
Mercenary Rule
mercenary rule: if you pay people only for output and give them no stake in the outcome, they be
Most Underrated Marketing Channel
most underrated marketing channel is the one your competitors ignore or undervalue — not the fla
Most Value Created After V1The first
version ships the idea; the real value is built in every iteration that follows. V1 proves the c
Multiplication
is creating value that scales with more of the same input — each unit of effort or asset produce
Next Best Alternative
next best alternative is what the other party would do if they didn’t choose you — their best op
Option Fatigue
fatigue is the paralysis that sets in when a customer or decision-maker faces too many choices.
Paradox of Specificity
paradox of specificity: the more narrowly you define who you’re for and what you do, the more st
Permission
is the right to ask for attention, time, or action — granted when you’ve earned trust or deliver
Persuasion Resistance
resistance is the pushback people feel when they sense they’re being sold or manipulated — they
Predictability
is the degree to which outcomes, behaviour, or process can be relied on — same inputs yield same
Preoccupation
is the state of being mentally occupied by something else — so that attention and capacity for t
Price Transition Shock
transition shock is the negative reaction — surprise, resistance, churn — when a customer faces
Pricing Uncertainty Principle
pricing uncertainty principle: you cannot fully know both the true value to the customer and the
Probable Purchaser
A probable purchaser is the person most likely to buy — not everyone who could, but the narrow s
Prototype
A prototype is a rough, early version built to test an idea before committing full resources. It
Psych Framework Customer Buying Journey
maps the customer buying journey through psychological stages — not just funnel steps. At each s
Qualification
is the process of checking whether a prospect has need, authority, budget, and timeline to buy —
Quality
is fitness for purpose taken to its extreme — the standard where every detail serves the user an
Quality Signals
signals are the visible cues that communicate a product or brand's standard before the buyer can
Reactivation
is winning back users or customers who have gone dormant — stopped using, stopped buying, or lap
Receptivity
is how open a person is to your message or offer at a given moment — attention, readiness, and w
Relative Importance Testing
importance testing measures how much each factor (feature, attribute, message) drives choice or
Reputation
is what others believe about you based on past behaviour — a summary of trust built or broken ov
Risk Reversal
reversal is shifting risk from the buyer to the seller — guarantees, free trials, money-back off
Social Status
status is one's relative position in a hierarchy that others care about. People seek to gain or
Sphere of Influence
of influence is the set of people, decisions, and outcomes you can actually affect. It's bounded
Strategic vs Financial Acquisition
buy companies for two broad reasons: strategic (capability, market, synergy) or financial (cash
Surfing
is the metaphor for riding a wave of change — technology, regulation, or demand — rather than fi
Systemization
is turning one-off or ad hoc work into repeatable processes, checklists, and standards so the ou
Technology Adoption Lifecycle
technology adoption lifecycle segments customers by when and why they adopt something new: innov
Three Universal Currencies
money, people and organisations trade in time and attention. Time is finite and irreplaceable; a
Throughput
is the rate at which a system produces its desired output — units shipped, deals closed, feature
Transaction
A transaction is a discrete exchange — something of value moves from one party to another in ret
Triage
is sorting items (tasks, opportunities, customers) by urgency and impact so you allocate limited
Value-Based Selling
selling prices and pitches based on the value the buyer receives, not the cost to deliver. A too
Version Two is Lie"Version Two" is
a lie because it rarely arrives as promised. When teams say "we'll fix it in V2," they're using
Weekly 1-1s
one-on-ones are a cadence: a fixed, recurring slot for each report to talk with their manager. T
Weird > Average
beats bland competence. "Weird" here means recognisably different — a clear point of view, a nar
Zero Tolerance
tolerance means no exceptions for certain behaviours or standards: one violation is one too many
Average Rule
multiple independent estimates or signals bear on the same quantity, combining them (e.g. by ave
Belady's Algorithm
algorithm (MIN or OPT) is the optimal offline page-replacement policy for a cache: evict the pag
Binary Search
search finds a target in a sorted sequence by repeatedly halving the search space: compare to th
Godwin's Law
: "As an online discussion grows longer, the probability of a comparison involving Nazis or Hitl
Interrupt Coalescing
coalescing batches multiple interrupt triggers into a single handling event. Instead of the CPU
Lagrangian Relaxation
relaxation turns a hard constrained problem into a sequence of easier ones: move constraints int
Laplace's Law
rule (or rule of succession) estimates the probability of an event that has occurred k times in
Least Recently Used
(Least Recently Used) is a cache eviction policy: when the cache is full, evict the item that wa
Multiplicative Rule
multiplicative rule says that for independent events, the probability of all occurring is the pr
Optimization Algorithms
algorithms search for the best solution in a space of possibilities: maximise reward or minimise
Packet Switching
switching sends data in small, discrete packets that can be routed independently across a shared
Scheduling & Prioritization
and prioritisation algorithms determine the order in which tasks are processed when resources ar
Sorting Algorithms
puts a sequence in order (e.g. by value or key). Different algorithms trade off time, space, and
Statistical Learning
learning is the framework for learning from data: choose a model class, define loss, and fit by
The Copernican Principle
principle says: don't assume a privileged position. We're not at a special time or place in the
The Gittens Index
index assigns a single number to each arm in a multi-armed bandit problem (with geometric discou
Threshold Rule
A threshold rule is a decision rule that triggers an action when a quantity crosses a level: "if
Upper Confidence Bound
(Upper Confidence Bound) is a simple policy for the multi-armed bandit: for each arm, compute an
Zawinski's Law
law (Jamie Zawinski, Netscape/Mozilla): "Every program attempts to expand until it can read mail
Abdication of Responsibility
of responsibility occurs when a party with decision rights or obligations shifts blame, cost, or
Bribery
is the use of payment or favours to distort a decision in the payer's favour. In economics it ap
Cancer Surgery Formula
cancer surgery formula is a decision heuristic: cut out the bad with clean margins and do not tr
Cap-and-trade Systems
is a market-based policy that sets a total limit (cap) on emissions or use of a resource and iss
Controlling the Center
the center is a strategic idea from chess and game theory: the player who dominates the central
Cooperative/Non-cooperative
game theory, games are cooperative when players can make binding agreements and share payoffs; t
Costs: Sunk/Transaction/Switching/Search
cost types shape decisions and markets. Sunk costs are already spent and irrecoverable — they sh
Factors of Production
requires inputs: in economics these are labour, capital, land, and often entrepreneurship. Labou
GDPGDP is the total value
oduct) is the total value of final goods and services produced in an economy over a period — usu
Game Theory: Combinatorial
game theory studies games with a finite set of positions, perfect information, and no chance — e
Game Theory: Discrete & Continuous
discrete games, players choose from a finite set of actions (e.g. cooperate or defect, enter or
Game Theory: Evolutionary
game theory studies how strategies spread in a population when payoffs determine reproductive or
Game Theory: Infinitely Long
a game is repeated indefinitely (no known last period), the set of equilibria expands. In the on
Game Theory: Mean Field
game theory studies settings with very many players where each player's payoff depends on their
Game Theory: Metagames
A metagame is a game about which game to play — or how to change the rules, the players, or the
Game Theory: Perfect & Imperfect Information
von Neumann / Oskar MorgensternIn perfect-information games, every player knows the full history
Game Theory: Pooling Games
signalling games, different "types" (e.g. high vs low quality) can send the same signal — a pool
Game Theory: Stochastic Outcomes
many games, the link between strategy and outcome is probabilistic: you choose an action, but th
Inflation
is a sustained rise in the general level of prices — the value of money in terms of goods falls.
Iron Law of Civilization
"iron law" (in some formulations) is that civilisation advances when the returns to productive b
NIMBYNIMBY — "Not In My Back
" — is the pattern where people support a policy or project in the abstract but oppose it when i
One Variable"One variable" thinking is the
discipline of changing or analysing one factor at a time while holding others constant — the exp
Product Lifecycle
product lifecycle is the sequence from introduction through growth, maturity, and decline. Deman
Purchasing Power Parity
power parity (PPP) is the idea that, in the long run, exchange rates should move so that a given
Seizing the Middle
the middle means positioning at the centre of a value chain or network so that participants on e
Simultaneous/Sequential
— in markets, negotiations, or competition — are either simultaneous (players act without knowin
Symmetry of Ignorance
symmetry of ignorance holds that in complex or novel problems, no single participant — designer,
TANSTAAFLTANSTAAFL — "There Ain't No Such
A Free Lunch" — is the principle that every benefit has a cost, even when it isn't visible. Some
Tiered Pricing
pricing offers a product or service at multiple price-and-feature levels so that different custo
3-6-3 Rule
3-6-3 Rule is the old banking joke: borrow at 3%, lend at 6%, and be on the golf course by 3pm.
AD-AS Model
(Aggregate Demand–Aggregate Supply) model is the standard macroeconomic framework for understand
Cockroach Theory
cockroach theory holds that when you see one piece of bad news, there are almost certainly more
Double Entry Accounting
entry accounting is the system in which every financial transaction is recorded in at least two
Fisher Effect
states that the nominal interest rate equals the real interest rate plus expected inflation: i =
Luxury Paradox
luxury paradox is that for certain goods, higher prices increase rather than decrease demand — t
Minsky Moment
is the sudden collapse of asset prices after a long period of growth fuelled by increasing specu
Negative Returns
returns describe the zone beyond diminishing returns where additional input actively makes the o
Pari-Mutuel System
a pari-mutuel system, all bets are pooled together and the payout is determined by the share of
Penny Problem Gap
penny problem gap is the disproportionate behavioural cliff between free and any positive price
Phillips Curve
PhelpsThe Phillips Curve describes the observed inverse relationship between unemployment and in
Say's Law
— "supply creates its own demand" — holds that the act of producing goods generates the income n
Agenda-Setting Theory
theory (Maxwell McCombs and Donald Shaw, 1972) holds that media may not tell people what to thin
Backwards Law
"backwards law" (often associated with Alan Watts and popularised in modern writing) is the idea
Bias Against Null Results
against null results is the systematic tendency to undervalue, ignore, or suppress findings that
Brandolini's Law
(the "bullshit asymmetry principle") states that the amount of energy needed to refute nonsense
Chimpanzee Test
is a simplicity heuristic: if you can't explain a concept clearly enough that someone with no do
Controlled Placebo
A controlled placebo is the practice of comparing an intervention against an inert baseline (the
Cunningham's Law
(attributed to Ward Cunningham, inventor of the wiki) states that the best way to get the right
Elon Musk's Law
(informal) is the principle that physics is the law, everything else is a recommendation. If som
Gate's Law
(often attributed to Bill Gates, closely related to Amara's Law) holds that we overestimate what
Hotel Bathroom Principle
is a heuristic: if the visible details are wrong, the hidden ones are likely worse. If a hotel b
Law of Large Numbers
of Truly Large Numbers states that with a large enough sample, any outrageous thing is likely to
Meta-Analysis
is the practice of combining results from multiple independent studies to find stronger, more re
Necessary Repeatability
repeatability is the principle that a result must be reproducible to be trusted. If an experimen
Okrent's Law
(attributed to journalist Daniel Okrent) states that the pursuit of balance can create imbalance
P-hacking
is the practice of manipulating statistical analysis — testing multiple hypotheses, adjusting va
Peer Review
review is the process of subjecting work — research, strategy, product decisions — to scrutiny b
Planck's Principle
principle — often paraphrased as "science advances one funeral at a time" — holds that new ideas
Reproducibility
is the requirement that a result can be independently obtained using the same methods. If you ru
Reverse Engineer
engineering is the practice of taking an existing outcome — a product, a strategy, a competitor'
Ribot's Law
éodule RibotRibot's law (Théodule Ribot, 1881) states that memory loss follows an inverse tempor
Schrodinger's Cat
ödingerSchrödinger's cat is a thought experiment: a cat in a sealed box is simultaneously alive
Skinner's Law
law — derived from B.F. Skinner's work in operant conditioning — holds that behaviour is a funct
Systematic Review
A systematic review is a structured method for synthesising all available evidence on a question
The Gatekeepers
are the individuals, institutions, or systems that control access to a resource, audience, or ma
The Great Temptation
great temptation is the pull toward expansion, diversification, or new opportunities at the expe
Veirordt's Law
von VierordtVeirordt's law (Karl von Vierordt, 1868) describes a systematic error in human time
Weber-Fechner Law
law states that human perception of change is proportional to the relative magnitude of the stim
Worm's Eye View
A worm's eye view is the perspective from the ground — the lowest level of a system, closest to
Accountability Partner
accountability partner is someone who commits to monitoring and reinforcing your follow-through
Batching
groups similar tasks into a single, uninterrupted block rather than scattering them across the d
Breathwork
uses deliberate breathing patterns to regulate the autonomic nervous system, shifting the body b
Chunking
compresses multiple pieces of information into a single cognitive unit, expanding the effective
Cold Exposure
exposure — cold showers, ice baths, cold plunges — triggers a acute stress response that produce
Commitment Devices
A commitment device is a choice you make today that restricts your future options in order to en
Digital Minimalism
minimalism is a philosophy of technology use where you deliberately reduce digital tools to only
Dual N-Back
is a cognitive training task that exercises working memory by requiring you to track two indepen
Elaborative Rehearsal
rehearsal is the process of encoding new information by connecting it to existing knowledge rath
Energy Management
management treats physical and mental energy — not time — as the fundamental resource to optimis
Environment Design
design is the practice of structuring your physical and digital surroundings to make desired beh
Implementation Intentions
intentions are pre-decided if-then plans that specify when, where, and how you will perform a be
Journaling
is the practice of writing regularly to clarify thinking, process emotions, track decisions, and
Keystone Habits
keystone habit is a single behaviour that triggers a cascade of other positive behaviours withou
Memory Palace
A memory palace is a mnemonic technique where you mentally place items you want to remember at s
Method of Loci
method of loci is a spatial mnemonic strategy — dating to ancient Greece — where information is
Note-Taking Systems
A note-taking system is a structured method for capturing, organizing, and retrieving informatio
Pomodoro Technique
structures work into 25-minute focused intervals separated by 5-minute breaks, with a longer bre
Single-Tasking
means doing one thing at a time with full attention. The case for it is neurological: the brain
Speed Reading
reading encompasses techniques designed to increase reading velocity while maintaining comprehen
Temptation Bundling
bundling pairs a behaviour you should do with a behaviour you want to do: only allow yourself th
Time Boxing
boxing allocates a fixed, non-negotiable period to a task and stops when time expires — regardle
Ultradian Rhythms
rhythms are biological cycles of roughly 90–120 minutes that govern periods of high and low cogn
Visualization Visualization — mental rehearsal
rsal of a desired outcome or process — engages many of the same neural pathways as physical perf
Algebra
is the practice of using symbols to represent unknown quantities and relationships, then manipul
Anscombe's Quartet
is a set of four datasets that share nearly identical summary statistics — same mean, variance,
Benford's Law
states that in many naturally occurring datasets, the leading digit is not uniformly distributed
Berkson's Paradox
is a statistical phenomenon where two variables that are unrelated — or even positively correlat
Confidence Intervals
A confidence interval expresses the range within which a true value likely falls, given the unce
Data Dredging
dredging — also called data fishing or data snooping — is the practice of searching through larg
Dimensional Analysis
analysis checks whether an equation or estimate makes sense by verifying that the units on both
Equivalence
is the recognition that two things different in form are identical in function, value, or logica
Error Bars
bars represent the range of uncertainty around a measured value. They show not just the estimate
Frequentist Statistics
statistics defines probability as the long-run frequency of events in repeated experiments. A co
Mean Median Mode
, median, and mode are three ways to summarize the "center" of a dataset — and they tell differe
Moderation
is the principle that the relationship between a variable and its outcome is often non-monotonic
Order of Approximation
of approximation is the practice of solving problems at the right level of precision for the dec
P-values
A p-value is the probability of observing data at least as extreme as the actual result, assumin
Permutations & Combinations
count the number of ways to arrange items when order matters. Combinations count selections when
Regression Analysis
analysis models the relationship between variables — identifying how changes in one or more inpu
Reliability of Case Evidence
of case evidence asks how much weight a single case — one customer story, one founder's success
Sampling
is drawing a subset from a larger population to make inferences about the whole. The power of sa
Statistical Significance
significance is the threshold at which an observed result is deemed unlikely enough under the nu
Stochastic Processes
A stochastic process is a system that evolves over time with inherent randomness — where the nex
Surface Area
area is the total exposed boundary between a system and its environment. In geometry, it determi
Variability
is the degree to which data points in a set differ from each other and from the central value. I
Variance
measures how far a set of outcomes spreads from the average. High variance means results swing w
36 Stratagems The 36 Stratagems are
tratagems are a Chinese collection of military and political tactics compiled from centuries of
Boots on the Ground
on the ground means committing real, physical presence to a situation rather than managing from
Call Your Bluff
a bluff means forcing an opponent to prove a claimed position or follow through on a threat — ex
Confusion
as a strategic tool means deliberately disrupting an opponent's ability to understand the situat
Crippling
means targeting the critical capability that an opponent depends on — not to destroy them outrig
Decapitation
means removing the leadership or decision-making centre of an opponent, collapsing their ability
Demoralization
means breaking an opponent's will to fight rather than their ability to fight. It targets psycho
Distraction
means drawing an opponent's attention and resources toward a secondary objective so the primary
Division
means splitting an opponent's forces, coalition, or resources so they can't concentrate their st
Erosion
is the strategy of gradually wearing down an opponent's resources, position, or resolve through
Fear
as a strategic tool means leveraging an opponent's anticipation of loss, pain, or failure to par
Fighting the Last War
the last war means applying strategies, structures, and assumptions that worked in a previous co
Flypaper Theory
theory holds that it's better to attract and concentrate threats in a single, controlled locatio
Fortification
means building defensive structures that make a position extremely costly to attack. In military
Overwhelm
means concentrating so much force, speed, or complexity on an opponent that their capacity to re
Provocation
means deliberately goading an opponent into an emotional, hasty, or poorly calculated response t
Punching Above Weight
above weight means a smaller force achieving disproportionate impact against a larger, better-re
Rumsfeld's Rule
categorises knowledge into four quadrants: known knowns (things we know we know), known unknowns
Sacrifice
means deliberately giving up something valuable now to gain a larger strategic advantage later.
Seeing the Front
the front means going to where the action is — the actual point of contact with customers, compe
Siege War
warfare means surrounding and isolating an opponent's position, cutting off their supplies, rein
Speed
as a strategic principle means that the rate of decision-making and execution is itself a compet
Stop the Bleeding
the bleeding means immediately stabilising a deteriorating situation before attempting any recov
Terrorism
as a strategic model describes the use of dramatic, high-visibility attacks designed to generate
Trench War
warfare describes a competitive stalemate where both sides are deeply entrenched in their positi
Turtling
means retreating into an extremely defensive posture — prioritising protection and survival over
Winning Battle but Losing War
the battle but losing the war means achieving tactical victories that come at such a high cost —
Zero-tolerance Policy
A zero-tolerance policy means establishing absolute rules with automatic, severe consequences fo
Alloying
is the process of combining two or more elements to create a material with properties superior t
Atomic Theory
complex is built from a finite set of simple, indivisible components. In physics, all matter red
Baton Passing
relay racing, the baton pass is the most critical moment — where speed is gained or lost. The me
Copernican Principle
holds that you are not special — your position, timing, or perspective is not privileged. Just a
Determinism
holds that every event is the inevitable result of prior causes. In physics, given perfect knowl
Electromagnetism
describes how electric and magnetic fields interact — invisible forces that attract, repel, and
Foundational Species
ecology, a foundational species creates and maintains the habitat that allows an entire ecosyste
Herd Immunity
immunity occurs when enough members of a group are protected against a threat that the threat ca
Heredity
is the transmission of traits from one generation to the next. In biology, DNA carries informati
Kinetics
is the study of rates — how fast reactions occur, not just whether they occur. In chemistry, a r
Memetic Theory of Conflict
theory, originated by Rene Girard, proposes that conflict arises not from scarcity or rational d
Memetic Theory of Desire
’s mimetic theory holds that human desire is not autonomous — we don’t want things because of th
Molecular Shape
chemistry, a molecule’s shape determines its function. The same atoms arranged differently produ
Nature vs Nurture
nature vs nurture debate asks whether traits are determined by genetics (nature) or environment
Peak Oil
oil describes the point at which extraction of a finite resource reaches its maximum rate, after
Polarity
describes the existence of two opposing but interdependent forces — positive and negative, attra
Potential
is stored capacity — energy, ability, or opportunity that exists but hasn't yet been converted i
Principle of Minimum Energy
of Minimum Energy states that systems naturally settle into the configuration requiring the leas
Quantum Mechanics
mechanics describes a world where outcomes are fundamentally probabilistic, not deterministic. A
Replication
is the process of copying a successful pattern with high fidelity. In biology, DNA replicates to
Resonant Frequency
system has a natural frequency at which it vibrates most efficiently. Apply energy at that frequ
Reward System
reward system is the brain's built-in mechanism for reinforcing behaviour. Dopamine — the neurot
Self-Preservation
is the fundamental biological drive to maintain one's existence. Every organism — from bacteria
Shannon-Hartley Law
theorem defines the maximum rate at which information can be transmitted over a communication ch
Sustainability
is the capacity of a system to maintain itself over time without depleting the resources it depe
The Chemical Bond
A chemical bond is the force that holds atoms together to form molecules. The bond forms because
The Chemical Reaction
A chemical reaction occurs when substances combine or break apart to form something new. Reactan
Viscosity
is a fluid's resistance to flow. High-viscosity fluids like honey move slowly; low-viscosity flu
Agnosticism
is the intellectual position that some questions cannot be answered with certainty — and that ho
Arrow's Impossibility Theorem
proves that no ranked voting system can perfectly translate individual preferences into a collec
Categorical Imperative
, Kant's foundational ethical principle, states: act only according to rules you could will to b
Common Law
law is a legal system built not from top-down legislation but from the accumulated weight of jud
Condorcet Paradox
de CondorcetThe Condorcet Paradox shows that collective preferences can be irrational even when
Constructivism
holds that knowledge, meaning, and social reality are not discovered but constructed through hum
Decline of Violence
the constant drumbeat of alarming headlines, violence has declined dramatically over centuries a
Distributive vs Procedural Justice
has two faces. Distributive justice asks whether outcomes are fair — did everyone get what they
Duty of Care
of care is the legal and moral obligation to act with reasonable concern for the safety and well
Duverger's Law
states that single-member district, winner-take-all electoral systems tend to produce two-party
Extremely Intense Ideology
intense ideology is the tendency for strongly held belief systems to distort thinking, override
Futarchy
is a proposed governance system where we "vote on values, bet on beliefs." Citizens define the g
Historical Wisdom
wisdom is the practice of using the accumulated lessons of history as a decision-making tool. It
Horseshoe Theory
theory proposes that the political spectrum is not a straight line from left to right but a hors
Law of Non-Contradiction
law of non-contradiction states that a proposition cannot be both true and false at the same tim
Limited Hangout
A limited hangout is a strategic disclosure of partial truth to prevent the full truth from emer
Negligence
is the failure to exercise the level of care that a reasonable person would exercise in the same
Political/Government Failure
or government failure occurs when government intervention in markets or society produces outcome
Presumption of Innocence
presumption of innocence is the principle that any person accused must be considered innocent un
Reasonable Doubt
doubt is the threshold of certainty required before acting on a conclusion — the standard that s
Sayre's Law
states that "in any dispute, the intensity of feeling is inversely proportional to the value of
State Capture
capture is the process by which private interests systematically redirect public institutions to
The Golden Mean
golden mean is Aristotle's principle that virtue lies between two extremes — excess and deficien
The Magic Ratio
HeaphyThe magic ratio — derived from John Gottman's research on marriages and later extended to
The Meaning of Life
meaning of life — as a mental model, not a metaphysical quest — is the recognition that humans p
The Platinum Rule
platinum rule is the upgrade to the golden rule: instead of "treat others as you would want to b
The Reasonable Person
reasonable person is a legal and philosophical standard: an imaginary individual of ordinary pru
Third Rail
A third rail is a topic, policy, or decision so politically dangerous that touching it destroys
Three Buckets of History
three buckets of history framework sorts historical events into three categories: things that ha
Abstract Blindness
blindness is the tendency to overlook or undervalue abstract factors — probabilities, systemic c
Ambiguity Bias
bias is the tendency to prefer options where the probability of a favorable outcome is known ove
Anecdotal Fallacy
anecdotal fallacy is using a personal experience or single example as proof of a general claim —
Appeal to Novelty
to novelty is the assumption that newer is better — that the latest idea, tool, or method is sup
Association Bias
bias is judging something by what it's linked to — people, brands, contexts — rather than by its
Aumann's Agreement Theorem
agreement theorem says that two rational agents who share a common prior and whose posteriors ar
Authority Bias
bias is the tendency to overweight the views or orders of people we see as authorities — titles,
Automation Bias
bias is the tendency to over-trust automated systems — algorithms, dashboards, tools — and to un
Belief Bias
bias is the tendency to judge an argument by whether we agree with the conclusion rather than by
Blind Spot
spot (in psychology) is the failure to see one's own biases and errors while readily seeing them
Blindspot Bias
bias is the belief that we are less biased than other people — that we see the world more object
Bright Spots
spots are the positive outliers — people, teams, or cases that succeed where others fail under s
Bucket Error
A bucket error occurs when you misclassify something by putting it in the wrong mental category
Burnout
is the state of chronic physical and emotional exhaustion caused by prolonged stress without ade
Catharsis
is the release of strong emotions through expression, producing a sense of relief or renewal. Ar
Caveman Syndrome
is the recognition that our brains evolved for a world radically different from the one we now i
Change Bias
is the systematic tendency to either overestimate or underestimate the impact of a change, depen
Cheerleader Effect
is the cognitive bias where individuals appear more attractive, competent, or impressive when pr
Cherry-Picking
is the practice of selecting only the evidence that supports your pre-existing conclusion while
Cognitive Scope Limitation
is the recognition that the human mind has a finite capacity for the range and complexity of pro
Compassion Face
is the phenomenon where people unconsciously mirror empathetic facial expressions and body langu
Conflict
is the inevitable tension that arises when individuals, teams, or organisations have incompatibl
Congruence Bias
is the tendency to test a hypothesis exclusively by searching for evidence that confirms it, rat
Conservatism Bias
is the tendency to insufficiently update beliefs when presented with new evidence. Even when con
Context Effect
is the principle that the environment, setting, and surrounding information fundamentally alter
Continued Influence Effect
describes how information that has been clearly corrected or retracted continues to shape thinki
Courtesy Bias
is the tendency to give opinions that are more socially acceptable or agreeable than one's true
Cryptomnesia
is the phenomenon where a forgotten memory returns without being recognised as such — you experi
Cult Indoctrination
describes the systematic process by which individuals are drawn into extreme group loyalty throu
Declinism
is the belief that society, an institution, or a situation is getting worse — and that the past
Distinction Bias
bias is the tendency to overvalue differences between options when evaluating them side by side,
Duration Neglect
neglect is the psychological finding that people judge an experience primarily by its most inten
Echo Chamber Effect
echo chamber effect is the amplification of beliefs that occurs when people are surrounded only
Effort Justification
justification is the tendency to value outcomes more highly when we've worked hard to achieve th
Egocentric Bias
bias is the tendency to overestimate our own contribution, perspective, or importance relative t
Eloquence
bias is the tendency to judge the quality of an idea by how well it is expressed rather than by
Emotional Contagion
contagion is the automatic, often unconscious transfer of emotions between people. Moods spread
Exaggerated Expectation
expectation is the tendency to expect outcomes — whether positive or negative — to be more extre
Excessive Fairness Bias
fairness bias is the tendency to prioritise equal treatment over optimal outcomes — distributing
Extremeness Aversion
aversion is the tendency to avoid the most extreme option in a set, regardless of its actual mer
False Consensus
consensus is the tendency to overestimate how many other people share our beliefs, values, and b
False Memory
memory is the phenomenon where we recall events that didn't happen or recall real events differe
False Precision
precision is presenting a number or estimate with more specificity than the underlying data supp
First-conclusion Bias
bias is the tendency to accept the first explanation or solution that comes to mind and stop sea
Focalism
— also called the focusing illusion — is the tendency to overweight a single aspect of an event
Forecast Bias
is the systematic tendency for predictions to skew in a consistent direction — typically toward
Gateway Drug Theory
proposes that exposure to a mild experience lowers the threshold for progressively more intense
Group Attribution Error
is the tendency to assume that the characteristics or decisions of a group reflect the preferenc
Humor Effect
is the cognitive phenomenon where humorous information is remembered better than non-humorous in
Hypernovelty
describes the modern condition of being surrounded by an endless stream of new stimuli — news, n
Ideological Bias
is the tendency to interpret information, evaluate evidence, and make decisions through the lens
Illusion of Skill
of Skill is the mistaken belief that consistent patterns in outcomes reflect genuine expertise r
Illusion of Transparency
of Transparency is the belief that your internal states — intentions, emotions, knowledge — are
Illusion of Validity
of Validity is the cognitive bias where high confidence in a judgment persists even when the evi
Impact Bias
is the tendency to overestimate the intensity and duration of emotional reactions to future even
Inattentional Bias
— sometimes called inattentional blindness — is the failure to notice fully visible and relevant
Inconsistency-Avoidance
is the brain's deep resistance to holding or acting on contradictory beliefs, ideas, or behaviou
Information Bias
is the tendency to seek more information even when it will not change the decision. It manifests
Ingroup Bias
is the automatic tendency to favour members of your own group — giving them more trust, more ben
Interpretation & Reinterpretation
describes the mind's constant process of assigning meaning to events — and then revising that me
Jealousy/Envy Tendency
is the deep-seated human impulse to feel pain at the success or advantages of others — particula
Least Effort Principle
states that when faced with multiple paths to a goal, humans (and most organisms) will reliably
Leveling & Sharpening
describes the systematic distortion that occurs when information passes through memory or commun
Liking/Loving Bias
is the tendency to distort your judgement in favour of people, products, or ideas you like or lo
Ludic Fallacy
— from the Latin ludus, meaning game — is the mistake of applying the clean, well-defined rules
Masked Man Fallacy
— also called the intensional fallacy — occurs when someone assumes that because they know somet
Mental Simulation
is the cognitive process of imagining how events will unfold — running scenarios in your mind be
Mere Exposure Effect
is the phenomenon where repeated exposure to a stimulus — a face, a brand, a song, an idea — inc
Momentum Bias
is the tendency to continue a course of action primarily because it's already in motion — not be
Multiple Tendencies
refers to the reality that human behaviour is rarely driven by a single psychological force. At
Negativity Bias
is the tendency for negative experiences, information, and emotions to have a disproportionately
Normalcy Bias
is the tendency to assume that because something has never happened before, it won't happen — or
Omission Bias
is the tendency to judge harmful actions as worse than equally harmful inactions — to feel that
Optimism Bias
is the tendency to overestimate the likelihood of positive outcomes and underestimate the likeli
Optimistic Probability Bias
is the specific tendency to overestimate the probability of favourable events and underestimate
Outcome Bias
is the tendency to judge the quality of a decision based on its outcome rather than the quality
Paradox of Knowledge
of Knowledge is the observation that the more you learn about a subject, the more you realise ho
Paranoia
, in the business context, is a heightened state of vigilance toward threats — real and imagined
Pareidolia
is the tendency to perceive meaningful patterns — particularly faces, shapes, or signals — in ra
Peltzman Effect
, named after economist Sam Peltzman, is the observation that safety measures often fail to redu
Pessimism Bias
is the tendency to overestimate the likelihood and severity of negative outcomes. While optimism
Physical/Psychological Pain Bias
describes the tendency for the anticipation and experience of pain — whether physical or emotion
Placement Bias
is the tendency for the position of information — where it appears in a sequence, on a page, in
Positivity Effect
is the tendency — especially pronounced with age and experience — to attend to, remember, and fa
Precision Bias
is the tendency to treat precise-sounding numbers as more credible and reliable than round ones,
Prejudice
is a pre-formed judgment about a person, group, or situation based on category membership rather
Present Bias
is the tendency to overweight immediate rewards relative to future ones, beyond what rational di
Primacy Effect
is the tendency for the first information received to disproportionately shape opinions, memory,
Pro-innovation Bias
is the tendency to overvalue new innovations, assuming they should be widely adopted while under
Procrastination
is the act of delaying important tasks in favour of less important but more immediately comforta
Projection Bias
is the tendency to assume that others share your current preferences, beliefs, emotions, or ment
Pseudocertainty Effect
occurs when people treat an outcome as certain even though it's merely probable, because the dec
Publication Bias
is the systematic tendency for studies with positive, significant, or novel results to get publi
Rashomon Effect
— named after Akira Kurosawa's film — describes how the same event produces multiple contradicto
Reason-Respecting Tendency
is the human inclination to comply more readily with a request when a reason is provided — even
Recency Illusion
is the belief that something you've only recently noticed must itself be recent. You learn a new
Reciprocation Bias
is the deep-seated compulsion to return favours, gifts, and concessions — even when the original
Reductive Bias
is the tendency to oversimplify complex, multi-causal phenomena by attributing them to a single
Restraint Bias
is the tendency to overestimate your ability to control impulsive behaviour. People who believe
Reward & Punishment
and Punishment is the foundational behavioural principle that organisms repeat behaviours that a
Ringelmann Effect
is the finding that individual effort decreases as group size increases. In a tug-of-war experim
Sapir-Whorf Hypothesis
Sapir-Whorf Hypothesis proposes that the language you use shapes how you think — not just how yo
Scarcity Bias
is the tendency to assign greater value to things that are scarce, limited, or dwindling in avai
Self-Enhancement Bias
is the tendency to perceive yourself as above average on desirable traits — intelligence, skill,
Self-Handicapping
is the strategy of creating obstacles to your own performance so that failure can be attributed
Self-Serving Bias
is the tendency to attribute your successes to internal factors — talent, effort, intelligence —
Self-consistency Bias
is the tendency to perceive your past beliefs, attitudes, and behaviours as more consistent with
Self-relevance Effect
self-relevance effect is the tendency for people to process and remember information more deeply
Semmelweis Reflex
is the automatic tendency to reject new evidence or knowledge because it contradicts established
Serial Recall Effect
serial recall effect describes how the position of information in a sequence determines how well
Simplicity Bias
bias is the tendency to prefer simple explanations and solutions even when the situation is genu
Sleeper Effect
sleeper effect is the phenomenon where a message becomes more persuasive over time as the recipi
Social Comparison Bias
comparison bias is the tendency to favour or disfavour people based on how they compare to us —
Social Desirability Bias
desirability bias is the tendency for people to answer questions and present themselves in ways
Stress-Influence Bias
bias is the tendency for acute stress to distort decision-making — narrowing attention, amplifyi
Subjective Validation
validation is the tendency to perceive a statement or piece of information as true if it holds p
Testing Effect
testing effect is the finding that actively retrieving information from memory strengthens long-
The Onion Brain
is the model that human cognition operates in layers — from fast, instinctive reactions at the c
Threat Lockdown
lockdown is the cognitive state where a perceived threat causes the brain to narrow focus, suppr
Three Men Make A Tiger
A Tiger is the ancient Chinese proverb that illustrates how repetition from multiple sources cre
Time-Saving Bias
bias is the tendency to overestimate the time saved when increasing speed from a slow pace and u
Trait Ascription Bias
ascription bias is the tendency to view oneself as relatively variable in personality and behavi
Turkey Illusion
turkey illusion — derived from Nassim Taleb's parable — describes the danger of inferring safety
Ultimate Attribution Error
ultimate attribution error extends the fundamental attribution error to groups. When members of
Uncertainty Avoidance
avoidance is the degree to which people feel threatened by ambiguous or unknown situations and c
Victim-blaming
is the tendency to attribute fault to the person who suffered harm rather than to the circumstan
Vividness Illusion
vividness illusion is the tendency to give disproportionate weight to vivid, emotionally charged
Zero-sum Heuristic
zero-sum heuristic is the default cognitive shortcut that treats most interactions as zero-sum —
Analytical Honesty
honesty is the discipline of letting data tell you what is true rather than what you want to hea
Bottlenecks A bottleneck is the narrowest
narrowest point in a system — the constraint that limits the throughput of everything downstream
Cessation
is the deliberate act of stopping — ending a process, product, initiative, or habit that no long
Change
is the transition of a system from one state to another. As a mental model, the insight isn't th
Context
is the surrounding information that determines how a signal is interpreted. The same data point,
Deconstruction
is the systematic dismantling of a complex whole into its component parts to understand how it w
Environment
is the set of external conditions that surround and influence a system. As a mental model, it re
Garbage In Garbage Out
in, garbage out (GIGO) states that the quality of a system's output is fundamentally limited by
Humanization
is the practice of reintroducing human perspective into systems that have become abstracted. As
KPIA Key Performance Indicator is a
quantifiable metric chosen to represent the health or progress of a system toward its goals. The
Margin of Error
of error is the range within which the true value of a measurement is likely to fall. Every meas
Measurement
is the act of assigning a number to an attribute of reality. As a mental model, the key insight
Norms
are the unwritten rules that govern behaviour within a system. They are distinct from formal rul
Process Overhead
overhead is the cost — in time, energy, and attention — of maintaining the processes themselves
Progressive Load
load is the principle of introducing complexity, demand, or change to a system gradually rather
Ratio
A ratio expresses the relationship between two quantities, revealing proportionality that absolu
Renormalization Group
renormalization group is a framework for understanding how a system's behaviour changes — or doe
Selection Test
A selection test is any mechanism that filters inputs into a system based on defined criteria. H
Spring-Loading
is the practice of storing energy, resources, or capability in advance so that when an opportuni
Sustainable Growth Cycle
A sustainable growth cycle is a self-reinforcing loop where growth generates the resources neede
The Middle Path
middle path is the principle that optimal system performance often lies between extremes rather
Tolerance
is the acceptable range of deviation a system can absorb before performance degrades or failure
Typicality
is the degree to which an instance represents the central tendency of a category. The more typic
Uncertainty
is the condition of incomplete knowledge about the current state, future outcomes, or causal rel
Hedgehog Concept
framework from Good to Great: find the intersection of what you can be the best in the world at,
Leverage
your output with labor, capital, or products with zero marginal cost.
Pathos
is the appeal to emotion — one of Aristotle's three modes of persuasion alongside ethos (credibi
Porter's Five Forces
competitive forces that determine why some industries are profitable and others are not.
Stockdale Paradox
after Admiral James Stockdale, the highest-ranking U.S. military officer held as a prisoner of w
Thought Experiment
A disciplined imaginative exercise used to explore the consequences of principles, test the limi
War of Attrition
A competitive strategy where victory goes to the side that can endure the longest. The objective