Guides
Long-form essays on learning, money, math, and life. Each one picks a single concept worth knowing well and gives you the mental model, the worked example, and the failure modes that the short version leaves out.
How to actually learn compound interest
Most people memorize the compound interest formula and still can't use it. Here's the mental model that makes it click — and the worked examples that prove it.
A no-bullshit guide to building a habit
Forget 21 days. Forget motivation. Real habit research says the lever is shorter, the timeline is longer, and most advice is backwards. Here's what actually works.
The Feynman technique, applied
Most explanations of the Feynman technique skip the part where you actually use it. This is the operator's manual — with worked examples and the failure modes nobody mentions.
Why most people never learn Bayes' theorem
Bayes' theorem isn't hard math. It's the most evolutionarily-resisted idea in statistics. Here's the model that makes it stick — and the trap your brain falls into every time.
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