On Sun, 23 Apr 2017 at 5:58 am, John Clark <[email protected]> wrote:
> 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. > But if the statue were conscious and it's consciousness not dependent on interaction with the outside world, it would still be conscious inside the marble block. Any physical object could be viewed as implementing a computation as anything could be mapped onto of a Turing machine, but the "work" of the computation would then be not in the physical object but in the mapping, a Platonic object. The problem with this is that such an implementation cannot interact with its environment, so you cannot, as you say to Bruno, use it to make money hiring out your Platonic computer. But what if we consider conscious computation that does not interact with the environment of its implementation? Like the statue in the block of marble, it would still be conscious even if no-one outside could appreciate it or make money out of it. The idea that computationalism implies that consciousness would occur independently of physical activity has been used as an argument against computationalism, on the grounds that it is self-evidently absurd. Hilary Putnam, originator of functionalism (of which computationalism is a subset), later realised this implication and changed his mind. John Searle and Tim Maudlin came to a similar conclusion. But an alternative is, as Bruno suggests, to keep computationalism and accept that the apparent physical world is secondary, not primary. The physical computers sold by Dell or IBM, along with everything else, are made in a virtual reality running on a Platonic computer. While this may at first glance seem absurd, there is no reason I can think of why it cannot be true. And it has advantages in addition to preserving computationalism, such as eliminating the need to explain why there should be a physical universe at all. 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. > -- Stathis Papaioannou -- 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.
