The quality of your mental models
Why does the quality of your mental models matter? Because good mental models are distinguished from bad by their ability to predict the future. And whether you’re making investments, building a car, ruling a country, curing cancer, or marketing shampoo, how you think the world works guides your actions. If your mental models predict the wrong thing, you are far less likely to achieve your goals. So test them against the real world and refine them with gusto.