How Logical Are You? (Psychology of Reasoning)

How Logical Are You? (Psychology of Reasoning)

So just how logical are you? This 4-card selection task developed by Peter Wason in 1963 will help you find out! All you need to do is assess which of the 4 cards must be turned over in order to determine whether the rule has been followed.

Music: “Brittle Rille” by Kevin MacLeod (
Music licensed under Creative Commons (

Sunrise footage by Beachfront B-Roll (

(Image credits coming soon)


March 6, 2015 / 43 Comments / by / in
  • If 2 is not a plausible answer then 7 is not one either since the rule cannot be flipped and it not logical to be able to prove the opposite. Also, their was no statement or rule that will allow it to be proven either. Therefore the conclusion is incorrect.

  • the wording of the question makes perfect sense. obviously, it's worded this way since it's a trick question and IT'S SUPPOSED TO CONFUSE/TRICK YOU. don't blame the question for your stupidity.

  • Did anyone else say K/7 ??

  • But you can't change the side of a card when you flip it over

  • Charlie Brown's other teacher

  • I see the same problem with this as I did with Pinker's demonstration.

    You MUST flip all the cards.

    If the rule is interpreted as "a card with a vowel must have an even number on the other side" then we must flip them all besides the K to see if the rule holds true. Furthermore, we must flip them all to validate the fist rule, which is that every card has a letter on one side and a number on the other.

    If the rule is interpreted as "if a card has a vowel, then it has an even number on the other side" then we need only flip the card with the vowel. Still we must flip them all to validate the first rule.

    This is alsol a critical step in discerning what rule might actually govern the symbols on the cards should one or both of the rules happen to be invalid.

    Basically, always flip them all and never take shortcuts because that would be stupid.

  • Actually it's very easy, I'd say even by nature that humans without training will conduct !A->!B out of A->B. It's common in the real world like summer is hot ->winter is not hot(cold). So, getting the answer wrong is not shameful, but we do need education.

  • I don't think that logic, on its own, could deduce the conclusion from that premise, but I think logic certainly can augment informal reasoning and intuition.

    The claim 'if there is a vowel on one side of the card then there is an even number on the other side of the card', for instance, you could negate and immediately decompose it, if you know the rules, as to see more clearly what needs to be true for it to be false.

    1. if x then y
    2. Not the case that if x then y
    3. x and not y

    'There is a vowel on one side of the card and there is not an even number on the other side'.

    Then, through a bit of intuition, you know that something is not even if and only if it is odd. So it may be easier to substitute 'not even' for 'odd' and say 'there is a vowel on one side of the card and there is an odd number on the other side'. I personally find talking in positive claims easier.

    Since that is only way that this can possibly be false, you could then think about each card, or some may realise that the truth of the conjunction solely depends on both conjucts being vowels or odd numbers, so you could then just choose any odd number and any vowel. Those are what you need. If you had hundreds of cards, you could easily just pick all of the odds and vowels in a flash.

  • first of all, cards has only A as a vowel.

  • Let me explain the rule of why 2 does not apply to be turned over… All MUSLIMS ARE NOT TERRORISTS, ALL TERRORISTS ARE MUSLIM.

    Plz solve

  • Can't understand the speakers accent, speak English dude

  • So really it's a test to see if people read the whole problem and is more of a word riddle

  • I got it right but personally it wasn't really hard just think about it for a minute or so and its easy enough

  • the accent annoyed the hack out of me …… i really want to keep watching the video but i couldn't…… =(

  • From reading the comments, I'd say some people need to brush up on their reading comprehension. The instructions are fine.

  • "This test features cards with letters on one side and numbers on the other side. [you] are then presented with four cards and a rule. If a card has a vowel on one side, it must have an even number on the other side. and the task is this: Which card(s) must be turned over to determine whether or not the rule has been followed."

    Now, please explain to me how that is confusing, and how it could possibly have been clearer. I mean, only 4% of people get it right, so is it really so strange that the average YouTube viewer would fail? Just because you failed, doesn't mean you're stupid, you're just part of the 96%.

  • Who else said K and 2

  • I got it right!!

  • He didn't calculate human emotions and its influence on "taking a test". Also, Western established rules of logic is different from other established cultures of logic.

  • As a point of interest, thirty years of research in cognitive psychology has demonstrated that participants typically perform poorly on abstract versions of the Wason selection task, whereas they perform well on deontic versions of the task. This finding is quite robust.

  • They pointed out that If the Card has a Vowel then the back must be an even number and Just because it is an Even number doesn't necessarily mean that the back is a Vowel. Because there must be a different unstated rule applied to the Even number. I get their point with the odd number which is 7. but what if there is also an unstated rule with the number 7 like the Even number 2.

  • GG

    Sufficient vs necessary problem. Ya'll fellow LSAT takers know wtf I'm talking about.

  • I didn't get the instruction, i thought you had to put one card over the other

  • This was really fascinating, I got the first question wrong saying A and 2 but as soon as I saw the beer water 25 16 version I instantly got it

  • Nice bit at the end about just because we can't be absolutely certain about something doesn't mean that it should be open for debate. Just because I can't prove that every single tiger has stripes doesn't mean that tigers don't have stripes, it's up to the other person to prove that they don't. Likewise it's up to people to prove that dinosaurs, evolution and climate change aren't real, which they can't

  • What the fuck is even happening

  • I still don't get it

  • illogical

  • what a horrible ear wrenching accent!

  • If turning over the 2 is irrelevant then shouldn't the 7 be irrelevant as well? Since we are not allowed to assume that the rule works both ways that should also discredit the reasoning behind turning over the 7. If the 7 had a vowel that still technically doesn't disprove the rule.

  • Symbolic logic!

  • "The key to this task is
    that you need to understand
    that you must try to falsify the rule
    not to confirm it".
    I failed because I tried to confirm the rule as most people does.

  • isn't the backgroundsound from kerbal space program?^^

  • Get a better mic or something. The audio quality is so low.

  • Get a better mic or something. The audio quality is so low.

  • If a card has a vowel of the side facing up, it must have an even number on the side facing down.

  • completely irrelevant to the video… but does anyone know where his accent is from?

  • It does not state the rule is one way. If I say, if a coin is heads up then the tails is down, then you can state if a tails is up it can also be tails down because it states direction as a variable. The question in this video doesn't even though the images of the cards could suggest this, it's not stated. Either the creator of video is representing this wrong or the original creator of the test is not actually logical but thinks he is so assumes his test is also.

  • You lost me at 1:19 I'm heading back to watch Rick and Morty. Peace Bitchess!

  • m

    Fuck, I got the question right and feel like dick after seeing all the people frustrated in the comments. Don't hate me, alright guys? I didn't ask to be a 4% freak (T_T)

  • I'm in the 4 proc 😀 wonder how many people were in the poles

  • I got it right! Must have been the Kerbal jazz.

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