> On 5 Aug 2019, at 15:04, John Clark <johnkcl...@gmail.com> wrote: > > On Fri, Aug 2, 2019 at 10:26 AM Bruno Marchal <marc...@ulb.ac.be > <mailto:marc...@ulb.ac.be>> wrote: > > > a physical computation is a computation realised by some physical object, > > but that does not made per se a computation into a physical notion. > > If nobody can find a computation that is not realized by some physical > object, and nobody can,
Everybody can do that, in the samùesense that everybody can find a prime number. A computation can be realised physically, but also arithmetically, as shown in all elementary textbook. Then, I do not assume the existence of the physical object, if only because I want to explain them. > then computation is a physical not a mathematical notion. No, that is insisting on your confusion between computation and physical computations. > Mathematical language can describe a computation Sure. But a computation is not the same as a description of computation, like the fact that 1 + 1 is 2 is different from the sequence of symbols "1 + 1 is 2”. > just as the English language can describe a cat, but the three letter English > word "cat" is not an animal and is not alive. Yes, some language used in mathematics can describe a computation, but that does not make a computation the same as a description of a computation. Computation are both describable in arithmetic, but also realised through the elementary arithmetical truth. You confuse again a model and a theory, semantic and syntax, a mathematical truth and its description. I think that you are stuck into your idea that mathematics is a language. Bruno > > > But using observable as a criterion of “reality” is equivalent with > > assuming Aristotle materialist ontology. > > Aristotle my ass! Emphasizing the importance of observation is equivalent to > emphasizing the importance of induction and of the scientific method and > emphasizing the non-importance of your airy-fairy new age woo woo. > > > I say we have to come back to Plato [...] > > I say the mention of a 2500 year old ignoramus is my cue to skip to the next > paragraph. > > > >> We know for a fact a Turing Machine made of matter > > >Turing machine are not made of matter. > > The type of Turing Machine that can change with time, that is to say the type > that can actually *do* something, the type that is amenable to the scientific > method, MUST be made of matter that obeys the laws of physics. No exceptions. Well, I guess, for a believer. I am not. > > > matter that obeys the laws of physics can emulate a Turing Machine made of > > matter that obeys the laws of physics. And we know for a fact that a Turing > > Machine made of matter that obeys the laws of physics is the only type of > > Turing Machine anybody has ever observed that can actually *do* something. > > > Yes, but matter does not need to be primitive for that. > > Matter may or may not be the ultimate in primitive, but if matter can do even > one thing that numbers can't (and even you admit that pure numbers can't > generate power but matter can) then matter must be more primitive than > numbers. Pure numbers cannot generate primitive energy or primitive matter, …, but who said that such things exist. We can doubt when we understand that pure number relations can generate the illusion of primitive energy, ... > > > > The people in arithmetic get the same experience as us when knocking a > > virtual “arithmetical” table, and argue correctly that they need to build > > physical machine if they want to interact with them, > > Maybe our world and even we ourselves are all a simulation, but if so then > the cosmic virtual reality program MUST be running on a computer made of > matter that obeys the laws of physics because matter has one key attribute > that arithmetic lacks, matter can change but arithmetic can't. And you can't > have computation without change. The change x -> s(x) is quite enough, to explain the psychological illusion of relative change. The change in arithmetic are not physical, making such computation arithmetical, but that explains why physical machine and physical computation seem to appear. If some “matter” plays a role in computation, then lambda calculus cannot be Turing universal, nor Turing machine, which are equivalent with respect to computations and digital processes to lambda calculus. There is just no physical postulate in the theory of computability. Only in the theory of physical computability. > > > >> If a Physical Turing Machine can produce a mind then there is no reason > >> another Physical Turing Machine could not emulate the machine that is > >> producing the mind. > > > But in that case, unless you put some magic in the notion of digital, the > > same emulation in arithmetic will produces the same effects. > > If arithmetic could emulate it then it would produce the same effect, but it > can’t. >From the points of view of the simulated people themselves, it does not make a >change. Or explain how. Buit as I said, it is simple to see that this will never work. If some “real matter” is needed, either it means that something non Turing emulable is needed for the mind, violating computationalism, or it is Turing emulable, and then is already emulated in arithmetic. > If we had some cream then we could have strawberries and cream, if we had > some strawberries. > > >> >> Arithmetical reality wouldn't even exist if matter that obeys the laws of >> >> physics didn't have the ability to make calculations if it's organized in >> >> the general sort of way Turing described. > > > Assuming Aristotle theology[...] > > And that is my cue to skip to the next paragraph because I believe in the > value of inductive reasoning and you have never said anything intelagent > after those three words. > > >>Nobody has found a non physical machine to emulate a physical machine, > >>indeed, we cannot make energy from natural numbers alone > So even you admit that there is at least one thing that physics can do that > pure mathematics can NOT. > > Assuming a [...] > > Assumptions be damned! You're claiming if you make one assumption you can > miraculously power a lightbulb with pure numbers but if you don't make the > assumption the bulb goes dark. That's called magical thinking, prove it works > by making the correct assumptions and start turning on light bulbs > unconnected to the electrical grid. Very easy, relatively to an observer who is also emulated in arithmetic. You come back with the knocking argument, which has been debunked by the Indian and greeks amore than 2000 years ago. That’s why I suggest you reread those old text, because you seem to keep argument debunked already at those time. Bruno > > 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 everything-list+unsubscr...@googlegroups.com > <mailto:everything-list+unsubscr...@googlegroups.com>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/CAJPayv09oLiBPyncjuFErVmdd1BwRtVFt_MF3H%2B2STnsmOfqjA%40mail.gmail.com > > <https://groups.google.com/d/msgid/everything-list/CAJPayv09oLiBPyncjuFErVmdd1BwRtVFt_MF3H%2B2STnsmOfqjA%40mail.gmail.com?utm_medium=email&utm_source=footer>. -- 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 everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/AA255126-D3E1-47AE-9B67-37157F4C5215%40ulb.ac.be.
