Instruments for better thinking.

Second-Order Thinking: And Then What?

Most people think about what happens next. Second-order thinkers ask what happens after that. It's a simple shift that changes almost every decision.

Inversion: Thinking Backwards to Move Forward

Charlie Munger's favourite mental model. Instead of asking how to succeed, ask how to guarantee failure — then avoid those things.

Fermi Estimation: Getting Comfortable with Approximate Answers

How many piano tuners are in Chicago? The point isn't the answer — it's the method. Fermi estimation is a toolkit for reasoning under uncertainty.