7. Your Brain Is Not Built for Probability
Kahneman and Tversky presented this classic scenario:
Linda is a 31-year-old woman who is deeply concerned with social justice. Which is more probable?
(A) Linda is a bank teller.
(B) Linda is a feminist bank teller?
Most people instinctively choose B — even though it’s logically impossible (B is a subset of A).
This isn’t about stupidity. It reveals how our brains are wired: System 1 (fast, intuitive thinking) dominates daily life. It’s quick, automatic, and loves shortcuts. System 2 (slow, logical thinking) is more accurate but lazy and energy-consuming. We rely on System 1 far more than we realize, which is why we constantly fall for probability traps.
What fascinates me lately is how AI LLMs like Grok and Claude can help fill some of these holes. The human brain acts fast and intuitively — that’s where most of our mistakes come from. But tools like AI can act as a kind of external System 2: slower, more deliberate, better at catching logical inconsistencies and base-rate neglect that our intuition misses.
I’m not saying AI replaces good thinking, but it can be a powerful aid — a reminder to pause and engage System 2 more often, especially in investing and life decisions where probability matters most.
Recognizing this has made me much more humble about my own judgments. I now try to catch myself and ask: Am I thinking with System 1 again? 🧠