  The psychologists Hugo Mercier and Dan Sperber challenge the assumption that complex knowledge resides in the beliefs of rational individuals (Mercier and Sperber 2017). Countless experiments over several decades have shown us to be on average very bad at reasoning on our own. One well-known case is the Wason selection test taken by thousands of subjects. In one version subjects have in front of them four cards with a number on one side and a letter on the other. They are asked which cards that show E, K, 2, or 7 would they turn over to determine the truth of the following statement: If a vowel is on one side there is an even number on the other. On average only 20% get the right answer. If they reason together in small groups, however, their success rate jumps to 80%. What accounts for this improvement?