Re: The simple essence of Proof Theoretic Semantics
dbush <[email protected]>
| Newsgroups | sci.logic,comp.theory,sci.math,comp.ai.philosophy |
|---|---|
| Organization | A noiseless patient Spider |
| Message-ID | <[email protected]> |
On 7/1/2026 2:21 PM, olcott wrote: > On 7/1/2026 1:15 PM, dbush wrote: >> On 7/1/2026 2:01 PM, olcott wrote: >>> On 7/1/2026 12:33 PM, dbush wrote: >>>> On 7/1/2026 10:40 AM, olcott wrote: >>>>> On 7/1/2026 6:55 AM, dbush wrote: >>>>>> On 7/1/2026 12:20 AM, olcott wrote: >>>>>>> On 6/30/2026 11:01 PM, dbush wrote: >>>>>>>> On 6/30/2026 11:49 PM, olcott wrote: >>>>>>>>> On 6/30/2026 10:17 PM, dbush wrote: >>>>>>>>>> On 6/30/2026 11:10 PM, olcott wrote: >>>>>>>>>>> On 6/30/2026 10:02 PM, dbush wrote: >>>>>>>>>>>> On 6/30/2026 10:57 PM, olcott wrote: >>>>>>>>>>>>> On 6/30/2026 9:34 PM, dbush wrote: >>>>>>>>>>>>>> On 6/30/2026 6:04 PM, olcott wrote: >>>>>>>>>>>>>>> On 6/30/2026 4:56 PM, André G. Isaak wrote: >>>>>>>>>>>>>>>> On 2026-06-30 15:45, olcott wrote: >>>>>>>>>>>>>>>>> On 6/30/2026 4:18 PM, André G. Isaak wrote: >>>>>>>>>>>>>>>>>> On 2026-06-29 21:06, olcott wrote: >>>>>>>>>>>>>>>>>>> On 6/29/2026 9:49 PM, André G. Isaak wrote: >>>>>>>>>>>>>>>>>>>> On 2026-06-29 20:42, olcott wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> Those are specific concrete examples of how >>>>>>>>>>>>>>>>>>>>> Proof Theoretic Semantics rejects expressions >>>>>>>>>>>>>>>>>>>>> as Proof Theoretic Semantically incoherent. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> No, they are not. No author writing in the framework >>>>>>>>>>>>>>>>>>>> of proof- theoretic semantics has ever offered those >>>>>>>>>>>>>>>>>>>> examples or comparable examples or made any claims >>>>>>>>>>>>>>>>>>>> about 'rejecting expressions as proof theoretic >>>>>>>>>>>>>>>>>>>> semantically incoherent'. And there's nothing >>>>>>>>>>>>>>>>>>>> incoherent about the statement 'no number is equal >>>>>>>>>>>>>>>>>>>> to its successor' which is the example under >>>>>>>>>>>>>>>>>>>> discussion. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> André >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> None-the-less what I have said remains completely true. >>>>>>>>>>>>>>>>>>> What I have spent 28 years reverse-engineering from >>>>>>>>>>>>>>>>>>> first >>>>>>>>>>>>>>>>>>> principles is exactly that. That no one applied PTS >>>>>>>>>>>>>>>>>>> exactly that way before does not mean that it is not >>>>>>>>>>>>>>>>>>> exactly correct PTS. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Unfortunately, your say so carries very little weight. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Yes. That is why I need to carefully find the exact >>>>>>>>>>>>>>>>> text that backs me up. Because PTS has their own >>>>>>>>>>>>>>>>> private author by author language it must be a >>>>>>>>>>>>>>>>> work written for a general audience like this work. >>>>>>>>>>>>>>>>> https://plato.stanford.edu/entries/proof-theoretic- >>>>>>>>>>>>>>>>> semantics/ >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Would you agree that there is a difference between a >>>>>>>>>>>>>>>>>> statement being false and a statement being meaningless? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> PTS is the way that meaning actually works. We can make a >>>>>>>>>>>>>>>>> simpler analogy in that English words are meaningless >>>>>>>>>>>>>>>>> until >>>>>>>>>>>>>>>>> they are defined. The PTS connection of an expression in >>>>>>>>>>>>>>>>> Q to its axioms Q is analogous to the connection of an >>>>>>>>>>>>>>>>> English word to its definition. A proof merely looks to >>>>>>>>>>>>>>>>> see if a definition exists and if it does not then the >>>>>>>>>>>>>>>>> English Word / Expression of Q remains meaningless. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> PTS counts a finite sequence of inference steps between >>>>>>>>>>>>>>>>> an expression and a set of axioms as the definition of >>>>>>>>>>>>>>>>> this expression. These are the two papers that establish >>>>>>>>>>>>>>>>> this Definitional View. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> None of the above answers my question: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Would you agree that there is a difference between a >>>>>>>>>>>>>>>> statement being false and a statement being meaningless? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I don't answer dumb questions. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Translation: >>>>>>>>>>>>>> >>>>>>>>>>>>>> "I don't answer questions that can prove me wrong" >>>>>>>>>>>>>> >>>>>>>>>>>>>>> That is why I am not responding to any posts >>>>>>>>>>>>>>> besides yours. dbush has become a troll again. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Reminding people that you admitted that disjunction >>>>>>>>>>>>>> intruduction is truth-preserving by your repeated >>>>>>>>>>>>>> dishonest dodging of how P can be true and P ∨ Q can be >>>>>>>>>>>>>> false is not trolling. >>>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> In Robinson Arithmetic (often denoted as Q), >>>>>>>>>>>>> the statement "no number is equal to its >>>>>>>>>>>>> successor" is not provable. While this statement >>>>>>>>>>>>> is true for the standard natural numbers, Robinson >>>>>>>>>>>>> Arithmetic is too weak to prove it universally >>>>>>>>>>>>> (∀ x, S(x) ≠ x). >>>>>>>>>>>>> >>>>>>>>>>>>> That you brought this up was a brilliant simplification >>>>>>>>>>>>> of the point that I was making proving that you can >>>>>>>>>>>>> understand the key ideas. >>>>>>>>>>>> >>>>>>>>>>>> What is was is a way to show more easily how you're wrong. >>>>>>>>>>>> That you claim that "no number is equal to its successor" is >>>>>>>>>>>> semantically invalid shows everyone that your ideas are >>>>>>>>>>>> worthless. >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> This is more accurate: >>>>>>>>>>> The truth value of (∀ x, S(x) ≠ x) >>>>>>>>>> >>>>>>>>>> So you admit that the above statement which exists in Q must >>>>>>>>>> be either true or false. >>>>>>>>>> >>>>>>>> >>>>>>>> Your lack of reply confirms your above admission. >>>>>>>> >>>>>>> >>>>>>> I make a very specific statement. >>>>>>> You mangle it and ask if I agree. >>>>>> >>>>>> There was no mangling. That is the meaning of the words you used. >>>>>> >>>>>>> >>>>>>> The truth value of (∀ x, S(x) ≠ x) >>>>>> >>>>> >>>>> You already mangled it. >>>>> The truth value of (∀ x, S(x) ≠ x) does not exist in Q. >>>> >>>> In your own words, what does it mean for the truth value of >>>> statement to not exist in a formal system? >>>> >>> >>> The same thing as: "cats are animals" expressed in >>> English has no English meaning in Chinese. >> >> I didn't ask for an example. I asked for a definition of what it mean >> for the truth value of a statement to not exist in a formal system. >> > > Wittgenstein (1937) > 'True in Russell's system' means, as was said: > proved in Russell's system; and 'false in Russell's > system' means: the opposite has been proved > in Russell's system I specifically didn't ask for an external quote, as you have demonstrated on countless occasions that you can't understand what others have written. Tell me, *in your own words*, what you think it means for the truth value of a statement to not exist in a formal system.