A mental model is a pattern in reality that shows up again and again. Once you recognize one, it starts to pop-up everywhere. Understand how it works, and you can recognize something deep about the universe.
Some of my favs on the list, his concise explanations are superb:
- Marginal Benefit matters more than averages.
- Compounding: Rate of growth depends on amount you already have. Applies to effort as well as assets.
- Feedback causing negative or positive loops.
- Nash Equilibria - a revealing human decision-making principle.