On Tuesday, May 14, 2019 at 7:29:07 PM UTC-5, Brent wrote:
>
>
>
> On 5/14/2019 9:49 AM, Jason Resch wrote:
>
> What is truth? (Pontus Pilate). Arithmetical statements are true if they 
>> are theorems derived from the axioms. 
>>
>
> This is false. In every consistent system of axioms there are statements 
> that are true but cannot be derived from the axioms. 
>
>
> That's not true. There are axiomatic systems that are complete.  
>
> In other words truth =/= proof, truth is always greater that what can be 
> proved.
>
>
> That's because you have recourse to an idea of "true" that is outside of 
> logical inference...such as "empirically true".
>
> Brent
>



An axiom system *A* being complete just means that for every (syntactically 
well-formed) sentence *s* in the language of *A*, either *s* or ~*s* can be 
proved via the rules of deduction of *A*.



BTW, while Church-Turing is not a useful "thesis", Curry-Howard is.

                          proofs = programs

(The informal word "model" does not come up in programming language theory 
- PLT - that I can surmise, except in the context of a "model of 
computation/programming" - lambda calculus, pi calculus, functional, 
process-oriented. Its use in physics is a bit confusing. For example, 
regarding the equation of the Standard Model as written out by mathematical 
physicist Matilde Marcolli:

     
https://www.sciencealert.com/images/Screen_Shot_2016-08-03_at_3.20.12_pm.png

is the equation itself of the Standard Model here a "model", or is the 
interpretation of this equation a "model"?)

@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/e9d026a6-8100-492f-a141-09c6aee4c6f0%40googlegroups.com.

Reply via email to