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The thread of paradoxes

  1. Jun 22, 2009 #1
    I thought it might be fun to have a thread to make your head explode!! By means of posting some of your favorite mind-bending paradoxes.

    I just heard a new one (for me) today that I thought was pretty good, thought I'd share!

    What if Pinocchio said "My nose will grow"?
  2. jcsd
  3. Jun 22, 2009 #2
    Suppose you have a ship in which one part fails each week. You replace the old broken part with a new part, scrapping the old part in some junk yard. Over the course of a few years, you have scrapped every original piece of the ship for new parts because all the old pieces of the ship broke. Is this the same ship? Here's the kicker: if we take all the original pieces and put them back together (suppose we repair them or whatever to make the parts work again) to make the same 'old' ship, is this the same ship? Does this mean we have two of the same ship?
  4. Jun 22, 2009 #3
    well, Pinocchio also said that he always lies...

    that's how we had a few extra air planes in the air force.
    Last edited: Jun 22, 2009
  5. Jun 22, 2009 #4
    The adult male barber who shaves all men who do not shave themselves, and no one else. Can he shave himself?

    If there is an exception to every rule, then every rule must have at least one exception, the exception to this one being that it has no exception.

    Is the word "heterological", meaning "not applicable to itself," a heterological word?

    A law student agrees to pay his teacher after winning his first case. The teacher then sues the student (who has not yet won a case) for payment.

    If truth does not exist, the statement "truth does not exist" is a truth, thereby proving itself incorrect.
  6. Jun 22, 2009 #5
    True, but that in itself is a lie, so his nose would just grow
  7. Jun 22, 2009 #6
    There was only one catch and that was Catch-22, which specified that a concern for one's safety in the face of dangers that were real and immediate was the process of a rational mind. Orr was crazy and could be grounded. All he had to do was ask; and as soon as he did, he would no longer be crazy and would have to fly more missions. Orr would be crazy to fly more missions and sane if he didn't, but if he was sane he had to fly them. If he flew them he was crazy and didn't have to; but if he didn't want to he was sane and had to. Yossarian was moved very deeply by the absolute simplicity of this clause of Catch-22 and let out a respectful whistle.
    "That's some catch, that Catch-22," Yossarian observed.
    "It's the best there is," Doc Daneeka agreed.
  8. Jun 22, 2009 #7
    A dog once told me that dogs can't talk.
  9. Jun 22, 2009 #8

    Ivan Seeking

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    Why do we drive on a parkway and park on a driveway?

    Why do we call the year having an extra day a "leap year"? Where is the leap?

    Hot-water heaters

    Why is there no mouse-flavored cat food? Why don't we find catfood made from mouse?

    Why is there cat food made from vegetables?
  10. Jun 22, 2009 #9
    Hahahahaahahaha... I've never thought about that before, but I have to admit, I literally laughed out loud when I read that one
  11. Jun 24, 2009 #10

    Ivan Seeking

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  12. Jun 24, 2009 #11


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    Why do two planes have a near-miss rather than a near-hit?
  13. Jun 24, 2009 #12


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    Why is 'abbreviation' such a long word?

    (Of course, these aren't paradoxes.)
  14. Jun 24, 2009 #13


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    And why is Dyslexia so hard to spell
  15. Jun 24, 2009 #14
    If you don't know how to spell a word, how can you look it up?
  16. Jun 24, 2009 #15
    Paradoxes are just roundabout ways of saying "X is not X"
  17. Jun 24, 2009 #16
    What is a synonym for thesaurus?
  18. Jun 24, 2009 #17
    More importantly, if you don't know how to spell a word, how would you know that you've found it after looking it up? :bugeye:
  19. Jun 24, 2009 #18
    That's why dictionaries give definitions. Also, you must have a rough idea how to spell a word so you simply look in the general area (for example if you can't spell aerodynamic, you would look for things like airo and if it isnt there you move onto aero.) and find the one you want (check it against the definition). Obviously, a few exceptions are things like xylophone, where, if you can't spell it you really are s******.

    Then again, these days simply misspell it in google and it will give you the correct spelling. "Did you mean..."
  20. Jun 24, 2009 #19
    If we want to check if human logic is right, we have to use... human logic.
  21. Jun 24, 2009 #20

    Chi Meson

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    And shouldn't there be a shorter word for 'monosyllabic'?

    Return to the OP...

    What is the set of all things that don't belong to a set?
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