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Which came first, the ##\exists## or the ##\forall##?

  1. Jul 27, 2013 #1
    I've always imagined that some mathematician or logician was looking for a cool way to write these quantifiers, and one of the following scenarios happened:

    1.)

    "Hey, I know, for "For All," I'll just take the letter "A" and flip it vertically, giving me this lovely ##\forall##. Then I'll just do the same thing with the letter "E" for "There Exists."

    But wait, the letter "E" is vertically symmetric, it'll look the same!" *flips it horizontally instead.


    2.)

    "Hey, I know, for "There Exists," I'll just take the letter "E" and flip it horizontally, giving me this lovely ##\exists##. Then I'll just do the same thing with the letter "A" for "For All."

    But wait, the letter "A" is horizontally symmetric, it'll look the same!" *flips it vertically instead.



    So the question is, what came first, the ##\forall## or the ##\exists##?
     
  2. jcsd
  3. Jul 27, 2013 #2

    micromass

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    From wiki:

    http://en.wikipedia.org/wiki/Quantification
     
  4. Jul 27, 2013 #3
    Another mystery dispelled by wikipedia.
     
  5. Jul 27, 2013 #4

    AlephZero

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    True but probably irrelevant. Both symbols are rotated through 180 degrees.

    Before computer typesetting, using metal type "upside down" was an easy way to get new symbols.
     
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