> On 8 Jul 2019, at 12:42, Philip Thrift <cloudver...@gmail.com> wrote: > > > > On Monday, July 8, 2019 at 4:58:32 AM UTC-5, Bruno Marchal wrote: > >> On 6 Jul 2019, at 13:32, Philip Thrift <cloud...@gmail.com <javascript:>> >> wrote: >> >> >> >> On Saturday, July 6, 2019 at 1:42:20 AM UTC-5, Bruno Marchal wrote: >> >>> On 6 Jul 2019, at 05:57, Philip Thrift <cloud...@gmail.com <>> wrote: >> >> >> Whatever logic it is, its semantics (of a theory in that logic) is the >> elephant in the room. >> >> - https://en.wikipedia.org/wiki/Semantics_of_logic >> <https://en.wikipedia.org/wiki/Semantics_of_logic> >> - https://en.wikipedia.org/wiki/Model_theory >> <https://en.wikipedia.org/wiki/Model_theory> >> e.g. Whereas universal algebra provides the semantics for a signature, logic >> provides the syntax. >> - https://plato.stanford.edu/entries/model-theory/ >> <https://plato.stanford.edu/entries/model-theory/> >> >> Semantics is the wild, wild west of logic. > > > You might try to make a point, perhaps. Semantic is obviously very important. > > Logic can be divided in three chapters: > > - theory of theories and proofs (cf Gödel) > > - semantics (Model theory) (cf Lowenheim, Skolem and Tarski, Mostowski, …) > > - the relation between, theories and models, that is the study of (all) > theories and all their semantics, usually through completeness and > incompleteness theorems. > > Semantic is the heart of “modern logic”. I do avoid using it here to much, > because it is quickly rather technical. I hope people have some idea that the > structure (N, 0, +, *) (which is the set N with the usual standard > interpretation of + and *) is a model of both RA and PA. I might say a bit > more in the glossary I am preparing. All “rich” theories have infinitely many > non isomorphic models, and by incompleteness no theories at all can study its > own semantics, but some theories can still say a lot about it, like its own > incompleteness. > > Bruno > > > > Semantics is real thing, so to speak, to me. > > There are two types of semantics: > > Fictional - regarding all the mathematical structures of standard model > theory you refer to above (Hartry Field)
The non standard model would be less fictional? The word “fiction” can be misleading. I prefer to use “immaterial”, or “spiritual”, or “mental”, perhaps. > Material - things/entities in the material world Those are important, but if we assume mechanism, I don’t think we can assume matter, but we can explain its appearances from the machine’s consciousness theory (theology) and test it empirically. Up to now, the evidences favours mechanism. > > > Semantics and substrates are connected, it not identical. That's my blog. I can’t really make sense of this. > > Also > > There is in my opinion no important theoretical difference between natural > languages and the artificial languages of logicians. (Richard Montague) For a monist, the difference between natural and artificial is artificial, and indeed natural for those entities which develop a big ego and feel different. Of course there is a difference between the formal languages and the “natural” languages, and Richard Montague attempt to develop a sort of polymodal rich lambda calculus for the treatment of natural language is very interesting. So I appreciate your opinion that there is no fundamental difference between those type of languages. When I was younger I have made a universal programming language (ANIMA° which was also a subset of natural language (English). You could ask the computer things like, “could you please find a file with some document on number in my computer, and if not, on the net?”. But it was very slow, and people prefer shortcuts … Bruno > > @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 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/4c4884c5-a658-4112-9602-dc8decf3f5aa%40googlegroups.com > > <https://groups.google.com/d/msgid/everything-list/4c4884c5-a658-4112-9602-dc8decf3f5aa%40googlegroups.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/A32397A8-28FC-48C9-9275-E452AEDEC370%40ulb.ac.be.
