Mea inu paradox

Ua ʻike ʻia kēia ʻōlelo ʻo "ka mea inu ʻona": "Aia kekahi i loko o ka pā, no laila inā inu ʻo ia, inu nā mea a pau o ka pā." ʻAʻole ia he mea koʻikoʻi inā hoʻoikaika kēlā kanaka i nā mea ʻē aʻe e inu a i ʻole aia kekahi puka hope, e like me kā mākou e ʻike ai i kahi manawa. He laʻana maikaʻi ia mai ka loiloi predicate makemakika.


Hoʻomaka mākou ma ka ʻōlelo ʻana ʻaʻole inu nā mea a pau i loko o ka hale pāpaʻa a i ʻole hoʻokahi kanaka i loko o ka pā hale inu ʻole. No laila ua kūpono ka hoʻokaʻawale ʻana o kēia hihia:

  1. Inu nā kānaka a pau. A laila inā inu kekahi i loko o ka pā, inu nā mea a pau o ka pā - no ka mea inu nā mea a pau.
  2. ʻAʻole inu kekahi kanaka. No ka mea inu ʻole, he ʻoiaʻiʻo inā inu lākou, inu nā mea a pau o ka hale pāʻani - ʻoiai ʻaʻole inu ke kanaka ( \(A \Rightarrow B\) he ʻoiaʻiʻo mau inā he wahaheʻe \(A\) .

Ma keʻano maʻamau, no kahi predicate kūʻokoʻa \(D\) a me kahi hoʻonohonoho ʻole ʻole \(P\) hiki ke hōʻike ʻia ka ʻōlelo penei:

$$\exists x\in P.\ [D(x) \Rightarrow \forall y\in P.\ D(y)]$$

Hope