Language, Proof & Logic 9.17 (9) Exercise












1












$begingroup$


The exercise 9.17 of Language, Proof and Logic course goes like this:




Start a new sentence file, and enter translations of the following sentences. This time each translation will contain exactly one $forall$ and no $exists$.





  1. All dodecahedra are not small [Note: Most people find this sentence ambiguous. Can you find both readings? One starts with $forall$, the other with $neg$. Use the former, the one that means all the dodecahedra are either medium and large.]




I have passed the assignment successfully and my translation was:
$$
forall x (Dodec(x) rightarrow neg Small(x))
$$



My question is what is the other ambiguous interpretation for that English language sentence that authors hint on (the one that starts from $neg$).










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  • 2




    $begingroup$
    The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
    $endgroup$
    – Hagen von Eitzen
    Oct 26 '18 at 11:12










  • $begingroup$
    @HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
    $endgroup$
    – Andrey Surovtsev
    Oct 27 '18 at 7:30


















1












$begingroup$


The exercise 9.17 of Language, Proof and Logic course goes like this:




Start a new sentence file, and enter translations of the following sentences. This time each translation will contain exactly one $forall$ and no $exists$.





  1. All dodecahedra are not small [Note: Most people find this sentence ambiguous. Can you find both readings? One starts with $forall$, the other with $neg$. Use the former, the one that means all the dodecahedra are either medium and large.]




I have passed the assignment successfully and my translation was:
$$
forall x (Dodec(x) rightarrow neg Small(x))
$$



My question is what is the other ambiguous interpretation for that English language sentence that authors hint on (the one that starts from $neg$).










share|cite|improve this question









$endgroup$








  • 2




    $begingroup$
    The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
    $endgroup$
    – Hagen von Eitzen
    Oct 26 '18 at 11:12










  • $begingroup$
    @HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
    $endgroup$
    – Andrey Surovtsev
    Oct 27 '18 at 7:30
















1












1








1





$begingroup$


The exercise 9.17 of Language, Proof and Logic course goes like this:




Start a new sentence file, and enter translations of the following sentences. This time each translation will contain exactly one $forall$ and no $exists$.





  1. All dodecahedra are not small [Note: Most people find this sentence ambiguous. Can you find both readings? One starts with $forall$, the other with $neg$. Use the former, the one that means all the dodecahedra are either medium and large.]




I have passed the assignment successfully and my translation was:
$$
forall x (Dodec(x) rightarrow neg Small(x))
$$



My question is what is the other ambiguous interpretation for that English language sentence that authors hint on (the one that starts from $neg$).










share|cite|improve this question









$endgroup$




The exercise 9.17 of Language, Proof and Logic course goes like this:




Start a new sentence file, and enter translations of the following sentences. This time each translation will contain exactly one $forall$ and no $exists$.





  1. All dodecahedra are not small [Note: Most people find this sentence ambiguous. Can you find both readings? One starts with $forall$, the other with $neg$. Use the former, the one that means all the dodecahedra are either medium and large.]




I have passed the assignment successfully and my translation was:
$$
forall x (Dodec(x) rightarrow neg Small(x))
$$



My question is what is the other ambiguous interpretation for that English language sentence that authors hint on (the one that starts from $neg$).







first-order-logic






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asked Oct 26 '18 at 11:09









Andrey SurovtsevAndrey Surovtsev

835




835








  • 2




    $begingroup$
    The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
    $endgroup$
    – Hagen von Eitzen
    Oct 26 '18 at 11:12










  • $begingroup$
    @HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
    $endgroup$
    – Andrey Surovtsev
    Oct 27 '18 at 7:30
















  • 2




    $begingroup$
    The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
    $endgroup$
    – Hagen von Eitzen
    Oct 26 '18 at 11:12










  • $begingroup$
    @HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
    $endgroup$
    – Andrey Surovtsev
    Oct 27 '18 at 7:30










2




2




$begingroup$
The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
$endgroup$
– Hagen von Eitzen
Oct 26 '18 at 11:12




$begingroup$
The other interpretation is what would be more properly formulated as "Not all dodecahedra are small", I suppose. Personally, I would never interprete the given sentence this way.
$endgroup$
– Hagen von Eitzen
Oct 26 '18 at 11:12












$begingroup$
@HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
$endgroup$
– Andrey Surovtsev
Oct 27 '18 at 7:30






$begingroup$
@HagenvonEitzen Thanks, it seems likely to be what they intended! Neither would I though! The statement of yours seems to be very fitting, but when I compare it with the original English sentence (even knowing the answer, presumably), seeing one as an interpretation of another still feels counterintuitive.
$endgroup$
– Andrey Surovtsev
Oct 27 '18 at 7:30












1 Answer
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There is a well-known saying "All that glitters is not gold"



The literal translation of this would be:



$$forall x(Glitters(x) rightarrow neg Gold(x))$$



but it is clear that what this saying really means is:



$$neg forall x(Glitters(x) rightarrow Gold(x))$$



Maybe that's the 'ambiguity' they are referring to? Though I must say, I think the only reasonable interpretation of "All dodecahedra are not small" is what you have, and "All that glitters is not gold" is just a very poor way of saying "Not all that glitters is gold"






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    $begingroup$

    There is a well-known saying "All that glitters is not gold"



    The literal translation of this would be:



    $$forall x(Glitters(x) rightarrow neg Gold(x))$$



    but it is clear that what this saying really means is:



    $$neg forall x(Glitters(x) rightarrow Gold(x))$$



    Maybe that's the 'ambiguity' they are referring to? Though I must say, I think the only reasonable interpretation of "All dodecahedra are not small" is what you have, and "All that glitters is not gold" is just a very poor way of saying "Not all that glitters is gold"






    share|cite|improve this answer









    $endgroup$


















      0












      $begingroup$

      There is a well-known saying "All that glitters is not gold"



      The literal translation of this would be:



      $$forall x(Glitters(x) rightarrow neg Gold(x))$$



      but it is clear that what this saying really means is:



      $$neg forall x(Glitters(x) rightarrow Gold(x))$$



      Maybe that's the 'ambiguity' they are referring to? Though I must say, I think the only reasonable interpretation of "All dodecahedra are not small" is what you have, and "All that glitters is not gold" is just a very poor way of saying "Not all that glitters is gold"






      share|cite|improve this answer









      $endgroup$
















        0












        0








        0





        $begingroup$

        There is a well-known saying "All that glitters is not gold"



        The literal translation of this would be:



        $$forall x(Glitters(x) rightarrow neg Gold(x))$$



        but it is clear that what this saying really means is:



        $$neg forall x(Glitters(x) rightarrow Gold(x))$$



        Maybe that's the 'ambiguity' they are referring to? Though I must say, I think the only reasonable interpretation of "All dodecahedra are not small" is what you have, and "All that glitters is not gold" is just a very poor way of saying "Not all that glitters is gold"






        share|cite|improve this answer









        $endgroup$



        There is a well-known saying "All that glitters is not gold"



        The literal translation of this would be:



        $$forall x(Glitters(x) rightarrow neg Gold(x))$$



        but it is clear that what this saying really means is:



        $$neg forall x(Glitters(x) rightarrow Gold(x))$$



        Maybe that's the 'ambiguity' they are referring to? Though I must say, I think the only reasonable interpretation of "All dodecahedra are not small" is what you have, and "All that glitters is not gold" is just a very poor way of saying "Not all that glitters is gold"







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Dec 23 '18 at 15:46









        Bram28Bram28

        61.9k44793




        61.9k44793






























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