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 2:01 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.