Conjunction fallacy

/kənˈdʒʌŋkʃən ˈfæləsi/ noun

Definition

The error of assuming that specific conditions are more probable than general ones when the specific is a subset of the general. People incorrectly judge the probability of two events occurring together as higher than the probability of one of them occurring alone.

Etymology

Identified by Amos Tversky and Daniel Kahneman in the 1980s, the term combines 'conjunction' from Latin conjungere (to join together) with 'fallacy.' Their famous 'Linda the bank teller' experiment demonstrated how representativeness heuristics override basic probability rules.

Kelly Says

Your brain thinks a detailed story is more likely than a simple one, even when logic says otherwise! This is why people bet on specific lottery number sequences or believe elaborate conspiracy theories over simpler explanations.

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