Mental Models & Tools
A reference collection of thinking tools used to improve judgement
Orientation
Mental models are simplified representations of how the world works.
They help reduce complexity, reveal trade-offs, and clarify consequences that are not immediately visible. No single model is sufficient. Judgement improves through the use of multiple models, applied deliberately and over time.
How are they used
Mental models are not instructions or advice.
They are used to:
frame situations
test assumptions
compare alternatives
anticipate second-order effects
They are most effective when revisited and combined.
Categories
Maxims & Rules of Thumb
Concise principles and reminders used to guide decisions and behaviour.
Heuristics, Biases & Fallacies
Common cognitive shortcuts and systematic errors that distort judgement.
Mental Models in General Decision Making
Foundational models used to reason about choice, trade-offs, and consequence.
Mental Models in Mathematics & Science
Models explaining systems, probability, feedback, and natural constraints.
Mental Models in Engineering & Design
Models focused on reliability, structure, failure, and optimisation.
Mental Models in Finance & Business
Models addressing incentives, capital allocation, competition, and growth.
Mental Models in Metacognitive Strategies
Tools for observing, regulating, and improving one’s own thinking.
Mental Models in Learning & Memory Aids
Techniques for acquiring, retaining, and recalling information effectively.
Over time, a small number of well-understood models shape most good decisions.
Depth matters more than volume.