On Thursday, June 20, 2019 at 5:10:56 AM UTC-5, Bruno Marchal wrote: > > > On 19 Jun 2019, at 12:42, Philip Thrift <[email protected] <javascript:>> > wrote: > > > > On Wednesday, June 19, 2019 at 5:04:26 AM UTC-5, Bruno Marchal wrote: >> >> >> On 18 Jun 2019, at 15:16, Philip Thrift <[email protected]> wrote: >> >> In >> >> *Embodied and disembodied computing at the Turing Centenary:* >> *Turing’s Titanic Machine?* >> by S. Barry Cooper >> >> http://www1.maths.leeds.ac.uk/pure/logic/computability/BarryTalks/titanic_CACM.pdf >> >> >> *As Samson Abramsky puts it (private communication communication, 2011):* >> *“Turing took traditional mathematical objects, real numbers, functions, >> etc. as the things to be computed. In subsequent work in computer science, >> the view of computation has broadened enormously. In the work on concurrent >> processes, the behavior is the object of interest. There is indeed a lack >> of a clear-cut Church-Turing thesis in this wider sphere of >> computation—computation as interaction."* >> >> Add "(embodied) experience" to "interaction". >> >> So there is a *beyond-CT* suggested in all of this. >> >> >> >> With all my respect to Barry Cooper and Samson Abramski, what they show >> is that there are other interesting notions, beyond computation. >> >> The provability notion is typically “beyond CT”, or beyond computation, >> but they are Turing emulable, like all interaction-like notion of >> computation are Turing emulable. >> >> And, yes, they are right, those notions does not admit a Church-Thesis. >> It is just simpler to not call them computation. Those other notions does >> not violate CT, and are often based on CT, more or less explicitly. >> >> Bruno >> >> >> >> >> > Just as G.Strawson says "matter is a mystery”, > > > That is a good insight. I did not wait Mechanism to be suspicious that the > notion of matter is nonsensical. > > > > > computation (what is it?) is a mystery, > > > > I don’t see why. On the contrary, it explains the explainable! > > > > > except in the certitude of the *received doctrine* of Church-Turing > Thesis. > > > On the contrary. Everyone agreed on all example of intuitively computable > functions, and it admits an intuitively simple and informal definition: a > function is computable if we can explain, with a finite list of words, how > to compute it on any input, in a finite time. > It just happens that we cannot defined “finite”, and then there has been > the discovery of the universal machine, and the empirical discovery that > all attempts to define formally the computable functions has always led to > the same class of functions. > Some people,like me (and Gödel) took many years to accept the high > plausibility of CT. > > Of course, also, there is no certainty here. There is no certainty in any > science. And CT is not a doctrine, it is a theory, unrefuted until now. > > Now, many confuse the notion of computation with some of its intensional > variants, to claim that CT is refuted or unwarranted, but that is just > ignorance. > > > > > > But "there are other interesting notions, beyond computation" just leads > to mysticism it seems, since *what are these "other interesting notions"?* > What's an example of one these? > > > Truth, provability, knowledge, observable, relativize computations, etc. > > > > > I know that neither you nor Cosmin will accept there is such a thing as > *experience > processing *(with entities - *experiences/qualia irreducible to > information/numbers* - because it is *unconventional computing*, > something it seems you don't think exists (even though there is an annual > conference of it). > > > Yes, and I have been invited to submit a paper, which I did. I have no > problem with this. Unconventional computing does not contradict CT, no more > than quantum computing. But they address problems which are not under the > topic of CT, and emphasise special aspect of some type of computation, but > all machines does that with the different modes of self-reference. Keep in > mind that the machine’s phenomenologies, can be proved to be NON > computable. Of course this used CT. In fact the whole interest of CT is > that it permits to define and study the non computable. Without CT, no > mathematician would say that the 10th problem of Hilbert has been solved > (negatively). (The problem of finding a method to solve Diophantine > equation). > > Almost all attribute of “codes” are provably non computable. > > Bruno > > > > many confuse the notion of computation with some of its intensional variants, to claim that CT is refuted or unwarranted, but that is just ignorance
Intensional semantics lies at the heart of (unconventional computing). While extrinsic semantics -------------- - *Denotational semantics <https://en.wikipedia.org/wiki/Denotational_semantics>*, whereby each phrase in the language is interpreted as a *denotation <https://en.wikipedia.org/wiki/Denotation_(semiotics)>*, i.e. a conceptual meaning that can be thought of abstractly. Such denotations are often mathematical objects inhabiting a mathematical space, but it is not a requirement that they should be so. As a practical necessity, denotations are described using some form of mathematical notation, which can in turn be formalized as a denotational metalanguage. For example, denotational semantics of functional languages <https://en.wikipedia.org/wiki/Functional_programming_language> often translate the language into domain theory <https://en.wikipedia.org/wiki/Domain_theory>. Denotational semantic descriptions can also serve as compositional translations from a programming language into the denotational metalanguage and used as a basis for designing compilers <https://en.wikipedia.org/wiki/Compiler>. - - *Operational semantics <https://en.wikipedia.org/wiki/Operational_semantics>*, whereby the execution of the language is described directly (rather than by translation). Operational semantics loosely corresponds to interpretation <https://en.wikipedia.org/wiki/Interpreter_(computing)>, although again the "implementation language" of the interpreter is generally a mathematical formalism. Operational semantics may define an abstract machine <https://en.wikipedia.org/wiki/Abstract_machine> (such as the SECD machine <https://en.wikipedia.org/wiki/SECD_machine>), and give meaning to phrases by describing the transitions they induce on states of the machine. Alternatively, as with the pure lambda calculus <https://en.wikipedia.org/wiki/Lambda_calculus>, operational semantics can be defined via syntactic transformations on phrases of the language itself; - - *Axiomatic semantics <https://en.wikipedia.org/wiki/Axiomatic_semantics>*, whereby one gives meaning to phrases by describing the *axioms <https://en.wikipedia.org/wiki/Axiom>* that apply to them. Axiomatic semantics makes no distinction between a phrase's meaning and the logical formulas that describe it; its meaning *is* exactly what can be proven about it in some logic. The canonical example of axiomatic semantics is Hoare logic <https://en.wikipedia.org/wiki/Hoare_logic>. ---------- may well be well-developed, both physical and experiential semantics of new kinds of programs - e.g. produced by synbio - that actually go out and live in the real world are not yet. But to call the UC researchers "ignorant" is just name-calling. @philipthrift -- 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/d7e6ea6b-ced6-4089-94ef-2cc8370f478e%40googlegroups.com.
