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How'd he know there was sh.it on his head?

  1. Aug 25, 2005 #1
    there are 3 men. they can see each other but not themselves.
    there is a piece of birdsh.it on each of their heads. they start laughing at each other.

    the wisest out of the 3 guys stops laughing, he stopped laughing because he figured he had sh.it on his head.

    how'd he figure it out?
  2. jcsd
  3. Aug 25, 2005 #2
    Answer in white If the wise one did not have ****, then the other two guys would see that and they would realize that the other non-wise guy would have nothing to laugh at unless he had **** on his own head. Then he would stop laughing. Since they didn't stop laughing, the wise one realized why.
  4. Aug 26, 2005 #3
    how long'd it take for you to do that problem?
  5. Aug 26, 2005 #4
    Less than 17 minutes.
  6. Aug 28, 2005 #5
    I think this one is similar with the 3 scientist birthday party, (each of them asked to wear a hat, either red or blue...someone else from the party asked them to raise a hand if they saw at least one blue hat.......all of them raised their hand.......and they have to figure out what is the color of their own hat..............only one can figured it........)
  7. Aug 29, 2005 #6
    My answer:
    He is bald.
  8. Aug 29, 2005 #7
    Great thought, edgardo.......you're must be a real genius.......
    Or, i think he can knew it 'coz it stinks.....? (never have seen sh*t from birds actually, anyone knows......?)
  9. Aug 30, 2005 #8
    he stinks something on his ****, but he is not sure whether it is **** or what , so he will bang his head on the other person's head, so he can see the mark on his shirt,body what ever.
  10. Aug 30, 2005 #9
    Lol, that's really hilarious.
  11. Sep 3, 2005 #10
    He can't figure it out.

    Here are all the possibilities:

    0 guys/w sh.t. Nobody laughs.
    1 guy/w sh.t. The other two laugh.
    2 guys/w sh.t They all laugh.
    3 guys/w sh.t They all laugh.

    There's no way to infer that you also have sh.t
    just because all three of you are laughing. You
    may or may not have it.
  12. Sep 3, 2005 #11
    I think all three guys have definitely sh.it on their heads, but the question is how one of the guys notices that he has sh.it on his own head.
    I haven't looked at jimmysniders answer yet, but he obviously has the correct answer?
    Bah, this is mind boggling....

    My 2nd try here (ok, I give several answers :D):
    Maybe he notices that whenever the two men look at him, they start laughing? Or he somehow manages that only 1 man can have a look at him and this man still laughs? His wife comes by and starts laughing about him? Flies start landing on his head? The man has read too many "induction proofs" in mathematics?
    Last edited: Sep 3, 2005
  13. Sep 3, 2005 #12
    Thoughts in bird poop white,

    It's a two step process, not only are the other dim guys laughing, but they're also not stopping right away.


    1 with 2 without - two laugh, one doesn't. Obvious all around.
    2 with, 1 without - all three laugh at first. then, one of the ones with realize that since he's looking at one with and one without, the one with shouldn't be laughing and stops.
    3 with - all three laugh. after a while, the bright one realizes that if this were the 2w1wo case (with him obviously being the wo, he knows the other two), then the one or both of the other two should, despite their relative dimness, have cracked this by now and stopped laughing. Knowing that the other two, while able to figure out the simpler case, wouldn't be able to see through this more complex case, he stops.

    The trick here is that the question is written in such a way that it's easy to see "laughing/not laughing" vs "clean/dirty" as the only parameter. In fact there are two more, the "keep laughing after a while/stopping" and a scale of the resoning capacity of the participants. The second is vital here, if these were totally random people there might be a posibillity that neither of them crack even the first part, hence laughing at each other indefinitly blissfully ignorant of their own situation or even that one or both of them don't see the humor in the first place. It's assumed that all involved have a degree of knowledge about how the others will and won't act. The solution is based on comparing how long it would these two take to grasp the 2w2wo situation to how long they are actually taking to do it. If they seem to take a long time or even not at all even though they ought, it may be resonable to assume this is actually the 3w scenario and you ought to quit laughing.
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