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The science behind it

The cards that could prove you wrong

Given a rule to check, most brains reach for the card that AGREES with it. The card that could break it sits ignored.

A rule says: if this, then that. Four cards each hide half their story.

Only two cards could ever prove the rule broken, and one of them never feels relevant.

Dress the same rule as a story about people, and suddenly almost everyone solves it.

Then and now

Half a century of card tasks converged on one lesson: human logic runs on content, and the same structure lands differently in symbols and in stories.

Wason, P. C. (1968)

Where it began

Reasoning about a rule

Quarterly Journal of Experimental Psychology, 20, 273-281

The founding demonstration: asked which cards test a rule, most people pick the confirming card and skip the one that could falsify it.

Ragni, M., Kola, I. and Johnson-Laird, P. N. (2018)

State of the art

On selecting evidence to test hypotheses: A theory of selection tasks

Psychological Bulletin, 144, 779-796

The modern synthesis of hundreds of selection-task studies: the pattern is robust, and content that connects to real obligations transforms performance on identical logic.

What we do and do not claim

Turning the wrong card here says nothing about intelligence. The task is famous precisely because almost everyone does.