A mental model is a compressed way of thinking about a category of problems, built from a field outside your own. The more models you carry, the fewer situations feel genuinely unfamiliar.
Inversion
Instead of asking how to succeed, ask what would guarantee failure, then avoid those things. It’s often easier to identify what destroys value than what creates it.
Second-Order Thinking
First-order thinking asks what happens next; second-order thinking asks what happens after that. Many decisions that look good in the short term (like habitually skipping practice for rest) create compounding costs.
Circle of Competence
Knowing the boundary of what you genuinely understand — and treating decisions outside it with far more humility — prevents overconfidence from masquerading as expertise.
Applying Models Without Overusing Them
Mental models are lenses, not laws. The goal isn’t to force every problem through the same framework, but to have several available and to notice which one actually fits the situation in front of you.
