An illogical logic test

SamSam · Apr 12, 2015

For those who care, here's the answer for the 'correct' set of instructions...

You are shown these four green cards and given the following prompt:

You are told these four cards have a letter on one side and a number on the other. You are given a rule about the four cards: If a card has a vowel on one side, then it has an even number on the other side. You are asked, which card(s) do you need to turn over in order to determine if the rule is true or false?
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This abstract form of the Wason selection task generally yields the following distribution of answers (Wason & Shapiro, 1971):
~ 45% pick the A card and the 4 card
~ 35% pick the A card alone
~ 7% pick the A card, 4 card, and the 7 card
~ 4% pick the A card and the 7 card [correct] ~ 9% pick other combinations of cards
The shocking thing about Wason’s results is that the logically correct (normative) answer is only chosen by about 4% of subjects (Wason & Shapiro, 1971). Although subjects clearly recognize the importance of selecting the A card, it is logical to select the 7 card as well, because in the event that it has a vowel on the other side, the rule would be violated (thus falsified). Conversely, there is no logical reason to select the 4 card because it is not possible for it to falsify the rule––whether there is a vowel or a consonant on the other side is irrelevant as there is no restriction on an even-consonant pair.
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The H card doesn't matter with these (correct) instructions, being a consonant. Using the flawed set of instructions, it may matter as there could be a vowel on the other side of the H, or not, depending on how you personally interpreted the ambiguous instructions.

ImaginaryNumber · Aug 13, 2015

Another fun challenge. The analysis and explanation, which you can read after making your choice, is the most interesting part.

Puzzle: Are You Smarter Than 20,897 Other New York Times Readers? | New York Times

ps
John Nash would be proud of me.

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An illogical logic test

SamSam Senior Member

ImaginaryNumber Imaginary Member

Chinese Logic (govt TV cable problems)