How To Use Mental Models Successfully

Mental models are frameworks for understanding the world. They help us solve problems and make decisions. By simplifying complex realities, mental models guide our concentration on key variables and their interactions, away from useless distractions. Examples include the 80/20 rule, opportunity cost, diminishing returns, the Semmelweis effect, and the curse of knowledge. Systematically using mental models empowers us to approach problems with clarity and avoid common biases, improving decision-making and problem-solving across disciplines.

To use mental models effectively, you need to diversify your toolkit by learning models from different fields. Physics, sociology, mathematics, economics, systems theory, and quantum theory, to name a few. For instance, the compounding effect from finance explains how small, consistent investments result in exponential growth. Whilst feedback loops from systems-thinking show how actions serve to reinforce or dampen outcomes. Combining these cross-disciplinary concepts helps us see connections and second-order consequences: small, consistent investments work like a positive feedback loop toward eventual financial freedom. Thus step one is, “What models might I apply here?”

Practice deliberate application. Once you have identified which model fits the situation, grab a tool from your shed and boost your cognition. For instance, try second-order thinking to evaluate unintended consequences from lowering your prices as a company. It might boost sales and revenues for you initially, but over time, erode brand value. Accordingly, apply inversion to see challenges backward. Instead of trying to succeed, try to fail. “What would guarantee failure?” and “What would I do if my goal was to fail?” Work backwards from there, identifying risks to avoid and weak points to address.

Shake up a cocktail. Mental models are most powerful when combined. A textbook case is using the map-territory relationship and Bayesian thinking in tandem when making decisions. The former reminds you that the map is only a depiction of the territory, not reality itself, and the latter forces you to update your beliefs based on the new evidence. Thus you stay informed. Sound decisions ensue. If you’re investing, you could pair opportunity cost—what else you could be doing with your time, effort, and money—and loss aversion—whether you are overvaluing losses in lieu of seeing gains. Layering models gives you a multidimensional view.

Rely on data and feedback. Regularly test your models against reality—the map-territory relationship in vivo—to refine their accuracy. For example, when using the 80/20 rule to prioritize your goals, tasks, and projects, track whether the top 20 percent genuinely delivers the expected impact. Over time, backing yourself with results improves your ability to select and adapt models to context. Not every nail needs a hammer. Be aware. Recognize when models break down. They are, after all, simplifications, and not absolute truths. Being open ensures your thinking is flexible and adaptive, enhancing your decision-making and problem-solving ability. What’s not to love?