On Sat, Apr 22, 2017 Stathis Papaioannou <[email protected]> wrote:
>> >> Suppose just for >> the sake of argument that non-physical computations did not exist, how >> would our physical world be different? There would be no difference. >> Therefore either >> non-physical computations >> do not exist or they do but are utterly unimportant, rather like the l >> uminiferous aether >> . >> > > > > This is equivalent to supposing that mathematical Platonism is false. > Not exactly. Einstein didn't prove the luminiferous aether didn't exist in the Platonic sense, he just proved it was unimportant. I suppose you could say in the vague way that Greek philosophers love that correct mathematical calculations exist independently of matter, but the trouble is incorrect mathematical calculations exist too, and the only way to differentiate the correct from the incorrect is by using matter that obeys the laws of physics. And separating the stuff we want from the stuff we don't is important, that's why we say Michelangelo's huge statue of David is 500 years old and not far older even though in the platonic sense David was inside a gigantic block of Carrara marble for 100 million years and all Michelangelo did was unpack it, he just removed the parts of the block that weren't David. Bruno likes to talk about Robinson Arithmetic but as far as I can tell even Raphael Robinson never claimed he had proven the existence of non-physical calculations, instead he showed that if you do certain activities in a certain sequence then you can produce correct mathematical calculations without producing any incorrect mathematical calculations. But without matter that obeys the laws of physics you can't "do" anything, that's why a book by itself can't perform a calculation or "do" anything else either, not even a book on Robinson Arithmetic. John K Clark -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
