Shortening the loop between encountering disconfirming evidence and actually updating. Not “being open-minded” as a disposition — the specific reflex of treating the flinch of being wrong as a signal to lean in, rather than a threat to manage.

Here’s why it beats everything else on compounding grounds. Almost every other cognitive upgrade — first-principles thinking, better mental models, probabilistic reasoning — improves the base of the exponential: how good a given thought is. Update speed improves the exponent: how many revision cycles you complete per year. Two people with identical raw intelligence diverge wildly over decades if one revises a wrong belief in a week and the other defends it for five years. Errors compound exactly like returns do. A wrong premise about your career, your market, your relationships doesn’t sit still — it silently distorts every decision built on top of it, and the interest accrues against you.

The mechanism that blocks fast updating is almost never logic, it’s identity. The moment a belief becomes part of who you are — “I’m a designer who thinks X,” “I’m the kind of person who Y” — disconfirming evidence stops being information and becomes an attack, and your brain deploys its full intelligence toward defense instead of revision. Smart people are worse at this, not better, because they’re better lawyers for their existing positions. So the trainable sub-skill is keeping your identity as small as possible: hold beliefs the way you hold positions in a portfolio, not the way you hold your name.

The trigger to train is physical. There’s a distinct sensation when reality contradicts your model — a half-second of confusion or irritation before the rationalization machinery kicks in. Most people paper over it instantly. The entire practice is catching that flinch and treating it as the single most valuable moment of your day, because it’s the only moment you’re in direct contact with the edge of your map. Everything after the flinch is either updating or cope.