# Useful Ideas
Mental models worth internalising. Sources include books, articles, and other writing.
| Idea | What it does |
| -------------------------------------- | ----------------------------------------------------------------------------------------------- |
| [[Activity-Level Analysis]] | Profitability belongs to activities, not industries |
| [[Base Rates]] | Start with how often things happen in general |
| [[Bayesian Probability]] | Update beliefs proportionally to evidence strength |
| [[Black Box Thinking]] | Treat failure as data; build systems that capture learning |
| [[Blake-Mouton Grid]] | Concern for people vs concern for results |
| [[Calibrated Questions]] | "How" and "What" questions that guide without commanding |
| [[Chesterton's Fence]] | Understand why something exists before removing it |
| [[Complex Adaptive Systems]] | Systems where agents adapt to each other—unpredictable but patterned |
| [[Complements]] | Products that make yours more valuable |
| [[Counter-Positioning]] | New model incumbents can't copy without damaging themselves |
| [[Crystals of Imagination]] | Products embody knowledge; the economy amplifies access to others' knowhow |
| [[Cynefin]] | Different domains need different approaches |
| [[Dancing with Systems]] | Work with system dynamics, not against them; respond rather than control |
| [[Deming's 14 Points]] | Quality comes from improving the system, not exhorting the workers |
| [[Earned Secrets]] | Proprietary understanding from deep operational experience; combine with enduring advantage |
| [[Effectuation]] | Start with means, let goals emerge; control the future rather than predict it |
| [[End-to-End Process]] | Own the whole process, not fragments; eliminate handoffs |
| [[Ergodic Hypothesis]] | Time average ≠ ensemble average; what matters is your path |
| [[Explore vs Exploit]] | Balance trying new things against using what works |
| [[Goodhart's Law]] | When a measure becomes a target, it ceases to be a good measure |
| [[Growth Mindset]] | Abilities develop through effort; failure is feedback |
| [[Hanlon's Razor]] | Never attribute to malice what's explained by incompetence |
| [[Herzberg's Two-Factor Theory]] | Hygiene factors prevent dissatisfaction; motivators create engagement |
| [[Inversion]] | Solve backward: avoid stupidity rather than seeking brilliance |
| [[Kantor's Four Player Model]] | Four communication stances teams need: Mover, Follower, Opposer, Bystander |
| [[Kelly Criterion]] | Size bets proportionally to edge; never bet everything |
| [[Law of Requisite Variety]] | Only variety can absorb variety—match complexity to environment |
| [[Little's Law]] | Cycle time = work in progress / throughput |
| [[Lognormal Distribution]] | Mean > median; estimates underpredict because tails are long |
| [[Loss Aversion]] | Losses hurt ~2x more than equivalent gains feel good |
| [[Marginal Gains]] | Break problems into parts; improve each by small amounts |
| [[Maslach's Six Factors]] | Burnout comes from chronic stress across workload, values, reward, control, fairness, community |
| [[McNamara Fallacy]] | Decisions based solely on numbers ignore what can't be measured—then assume it doesn't exist |
| [[Mimetic Desire]] | We want what others want; desire is imitative, not autonomous |
| [[Mintzberg's Managerial Roles]] | What managers actually do: 10 roles across interpersonal, informational, and decisional |
| [[Multi-Armed Bandit Problem]] | Balance exploration and exploitation dynamically |
| [[Network Effects]] | Value increases as more people use it—winner-take-most dynamics |
| [[OODA Loop]] | Observe → Orient → Decide → Act; speed of iteration wins |
| [[Optimal Stopping]] | When to stop searching and commit (37% rule) |
| [[Optionality]] | Prefer choices that keep options open; asymmetric upside |
| [[POSIWID]] | The purpose of a system is what it does, not what it claims |
| [[Process Power]] | Operational excellence that takes years to replicate |
| [[Process vs Outcome]] | Judge decisions by quality of thinking, not results |
| [[Recognition Primed Decision Making]] | Experts pattern-match, then mentally simulate |
| [[Ringelmann Effect]] | Individual effort decreases as group size increases |
| [[Scale Economies]] | Unit costs decline as volume increases |
| [[Scale Economies Shared]] | Pass scale savings to customers; create compounding loyalty flywheel |
| [[Schopenhauer's 38 Stratagems]] | Rhetorical tricks for winning arguments regardless of truth—a guide for defence |
| [[Second-Level Thinking]] | Ask "and then what?"—first-level thinking is consensus |
| [[Secretary Problem]] | Explore first 37%, then pick first option better than all explored |
| [[Self-Image]] | Performance equals self-image; change identity to change results |
| [[Skin in the Game]] | Only trust those who bear consequences of their advice |
| [[Switching Costs]] | Friction that keeps customers from leaving |
| [[Systems Thinking]] | See interconnections, feedback loops, and delays—not just events |
| [[Tacit Knowledge]] | Knowledge you can only get from doing, not reading |
| [[Tactical Empathy]] | Understand their world to influence their decisions |
| [[The Barbell Strategy]] | Combine extreme safety with small high-risk bets; avoid the middle |
| [[The Five Focusing Steps]] | Identify constraint → exploit → subordinate → elevate → repeat |
| [[The Value Stick]] | Strategy = raise WTP or lower WTS; capture the spread |
| [[Theory of Constraints]] | System output is limited by one bottleneck; fix that first |
| [[Via Negativa]] | Improve by removing, not adding; less is often more |
| [[Viable System Model]] | Five functions every organisation needs to survive |