On Sun, Jul 21, 2019 at 8:46 AM Bruno Marchal <[email protected]> wrote:
> >There is nothing abstract or immaterial about a paper tape and a >> read/write head, but everything is abstract and immaterial about a >> sequence of ASCII characters in Lambda calculus. > > > *> Or about Turing quintuplets.* > Turing quintuplets are abstract and immaterial, a Turing Machine is not. > *> You keep confusing a digital machine, its code, its physical > implementation, …* > You keep confusing stuff that can *do* things from stuff that can not. A sequence of ASCII characters can't *do* anything unless it interacts with a brain made of matter that obeys the laws of physics, and the exact same thing is true of digital machine code. Lambda Calculus and Turing quintuplets can't *do* anything unless they interact with the physical brain of a mathematician, but a Turing Machine needs nothing else that is physical because it is already physical. All by itself a Turing Machine can simulate Turing quintuplets but Turing quintuplets CAN NOT simulate a Turing Machine, therefore a Turing Machine is more profound and fundamental and Turing quintuplets are a superficial way to think about it. 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 view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAJPayv0zuCHZKyY5ouNtrqNZPEmo3N7b5qo9yv2RjoSp%3DcKVLg%40mail.gmail.com.
