Mental Models

Mental Models articles on When Notes Fly, part of our Concepts coverage. Browse the 4 pieces below — newest first. Start near the top for foundational explainers, or scroll for deeper case studies and applied frameworks.

This section collects When Notes Fly's writing on Mental Models within our broader Concepts coverage. Each piece aims to give you a working understanding you can apply — the core idea, the evidence or examples behind it, and where it fits with related topics — rather than a quick definition you forget. Where a question is genuinely open or the evidence is mixed, the articles say so instead of overstating certainty. Articles link out to related reads across the site, so you can follow a thread from a single explainer into the wider topic.

How to use this page: if you are new to Mental Models, start with the most foundational explainers near the top and read them in order, since later pieces often build on the vocabulary and frameworks the earlier ones set up. If you arrived with a specific question, scan the titles and short summaries below to jump straight to the closest match, then follow its in-article links to go deeper. Each article is written to stand on its own, so you do not have to read the whole section to get value from any one piece. Taken together, the articles here trace how the ideas in Mental Models connect — what the established research agrees on, where practitioners still disagree, and how the concepts show up in everyday work and decisions. We update and expand this section as the topic develops and as new questions come up from readers, so it is worth returning to rather than treating as a fixed list.

See the full Mental Models archive, the site-wide archive, or our RSS feed. How we research and review articles: editorial standards.

Articles in Mental Models

• Ockham's, Hanlon's, and Chesterton's Razors Explained — Expert-written explanation of three classic reasoning heuristics with when to apply each, common misapplications, and decision examples.
• When to Use First Principles vs Systems Thinking — Expert-written comparison of first principles thinking and systems thinking with decision criteria for when each produces better results.
• First Principles Thinking: Elon Musk's Approach Explained — First principles thinking explained from Aristotle to Elon Musk. The five-step method, real examples from SpaceX battery costs to pharmaceutical...
• Cognitive Biases Everyone Falls For — Fifteen cognitive biases that distort reasoning, each paired with a peer-reviewed example and a practical countermeasure you can apply immediately.