Classic Traps

Walk into the classics — intuition, probability, statistics, decision and logic traps — get fooled once, get immune for good.

Unit 1

Intuition Traps

Three grade-school arithmetic questions that fooled half of MIT — meet System 1's blurted answers and System 2's laziness, get fooled first, then learn to hit the slow-thinking switch.

1Intuition Traps: Why the Answer That Pops Up in 3 Seconds Is So Often WrongFrom bat-and-ball to doubling lily pads — three CRT 'grade-school' questions fooled half of MIT; meet System 1's blurting, System 2's laziness, and the cognitive miser, and learn to hit the slow-thinking switch when it counts10 Q

Unit 2

Probability Traps

Switch or stay at Monty Hall's doors, how far to trust a witness, whether red is 'due' — work through the most counterintuitive probability classics yourself and build Bayesian intuition that can actually save you.

1Probability Traps: Switching Wins 2/3, a Positive Test Means ~2%, and the Wheel Owes You NothingThe Monty Hall problem, the taxicab and the doctors' test, Monte Carlo 1913 and the hot-hand saga — answer in your head first, then see the breakdown, and load Bayesian intuition with natural frequencies10 Q

Unit 3

Statistical Traps

From Wald's bullet holes to Berkeley's admission rates: see through survivorship bias, Simpson's paradox, regression to the mean, sample-size neglect, and misleading charts — rule out statistical artifacts before reaching for causal stories.

1Statistical Traps: Should You Armor Where the Bullet Holes Are? — Survivorship Bias, Simpson's Paradox, Regression to the Mean, and Charts That LieWald inferring the downed planes from the ones that returned, Berkeley's admission rates reversing in aggregate, flight instructors' illusion that scolding works — the numbers aren't faked, yet the impression can be entirely fake; rule out statistical artifacts before reaching for causal explanations10 Q

Unit 4

Decision Traps

Anchoring, sunk cost, framing, loss aversion, and the endowment effect — step on the five classic decision traps yourself, armed with the original experiments' numbers.

1Decision Traps: the Rigged Wheel, the Season Tickets You Must 'Get Your Money's Worth' From, and the Mug Nobody Would SellAnchoring, sunk cost, framing, loss aversion, and the endowment effect — irrelevant numbers hijack your bids, money already spent hijacks your choices, and the same numbers reworded flip the majority; get fooled once, get immune — even experts aren't exempt10 Q

Unit 5

Logic Traps

The Linda problem, 2-4-6, the four cards, and the letter K — fall into the classic experimental traps yourself, and see how similarity, positive instances, and ease of recall impersonate probability, evidence, and frequency.

1Four Classic Logic Traps: Linda, 2-4-6, the Four Cards, and the Letter K — Get Fooled Once, Get Immune85% fall for the Linda problem, only 21% crack 2-4-6 on the first try, and the abstract four-card task is solved by fewer than 10% yet 74% in a drinking-age setting — how similarity, positive instances, and ease of recall impersonate probability, evidence, and frequency10 Q