the building blocks of making

better decisions


Mental models are a way of explaining how things work. Throughout our lives, we build up a personal collection of mental models to understand the world around us.

Mental models aren't perfect but developing a rich toolbox of them can be useful in navigating the complexities of life. Learning to intuitively apply the right models in the right situations is something we develop with practice.

This website is a curated collection of models with broad applicability in everyday life. There’s a focus on brief descriptions and simple, real life examples of the models in use.

Weekly Mental Model

Goodhart's Law

When a measure becomes a target, it ceases to be a good measure.


Goodhart's Law highlights the issue with focusing solely on the value of a measure as an indication of success or progress. Often, observers will artificially change their behavior to reach a target without caring about the reason for the measure. In other words, they'll try to game the system. The law was originally stated as: "Any observed statistical regularity will tend to collapse once pressure is placed upon it for control purposes."


  • Google's PageRank algorithm would rank websites based on the number of incoming links from other websites. This led to webmasters gaming the system by artificially increasing the number of links to their website.

  • A company requiring writers to write a specific number of words a day will probably produce low quality, filler content as writers try to meet their quota.