Logic test answer






Card A: if it has an even number on the other side, the theory is wrong

Card 6: if it has a vowel on the other side, the theory is wrong.


Not needed:

Card B: Consonants could have odd or even numbers without affecting the theory.

Card 7: Odd numbers could have vowels or consonants without affecting the theory.


When I first came across this test in the 1970s, about 10% of graduates got it right. I would guess that people tend to look for proof that a theory is right, but not for evidence that it is wrong.