One of the deepest insights from rigorous first principles thinking is that the world undergoes structural changes that render historical patterns unreliable. As the economist Woody Brock puts it: "History rhymes, but it does not repeat itself."

When the underlying structure of a system changes, extrapolating from the past becomes dangerous. The assumptions that held true before may no longer apply. This is why first principles thinking is so valuable: it allows you to reason from fundamental truths rather than historical patterns.

In this topic, you will learn to identify structural changes, distinguish them from cyclical fluctuations, and adjust your thinking when the rules of the game have changed.