# The Reasoning Test Psychologists Still Can't Explain

An episode of [The Rest Is Science](https://invisiblenetwork.ai/podcast/1853007888), 20 Apr 2026, 1 h 02 min.

Audio: https://pdst.fm/e/traffic.megaphone.fm/GLT2805053573.mp3?updated=1776704549

Why do almost all of us struggle with a simple reasoning test, yet get it right the moment it’s about a pint in a pub? This week, Professor Hannah Fry and Michael Stevens take on the Wason Selection Task, one of the most intensely studied problems in the history of psychology. They unpack why a rule involving letters and numbers can feel strangely difficult, while the exact same logic becomes immediate and instinctive when it’s about people, rules, and catching someone out. From counterexamples and conditional statements to confirmation bias and the limits of human reasoning, they reveal why we rarely look for what proves us wrong. Along the way, they tackle a bigger question: did reasoning evolve to uncover truth, or simply to help us get along? ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit https://cancerresearchuk.org/restisscience Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by clicking here. ------------------- Video Producer: Adam Thornton + Oli Oakley + Jack Meek Animator: Sam Benson Video & Social: Bex Tyrrell Assistant Producer: Lucy Lipscombe Producer: Simona Rata Senior Producer: Lauren Armstrong-Carter Head Of Digital: Samuel Oakley Exec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

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