A SMALL LIBRARY FOR LARGE IDEAS

Know the numbers.
Keep the model.

Compact, information-dense field notes on how the world works, with the back-of-the-envelope numbers worth remembering.

Choose a rabbit hole

4 EXPLANATIONS

Explore reserves, production, refining, trade, consumption, energy mixes, and the strange journey inside one barrel.

SPY made 10.9% a year from 2006–2025. A taxed day trader needed about 15.8% gross to finish with the same money. Here is why.

Countries read like earnings reports, then the AI build-out: who lends the money, where it goes, and what it takes to pay back.

Winning players play about 23 of every 100 hands. See all 169 starting hands, the odds of common draws, and what each bet size asks of a caller.