Then why bother with a machine/program? You have simply gone to the trouble of creating a data-base - in theory because there are significant problems im creating one for real. — tim wood
Assuming then it returns true for all true strings and false for all false ones, right?My True(L,x) predicate is defined to return true or false for every
finite string x on the basis of the existence of a sequence of truth
preserving operations that derive x from — PL Olcott
So with this assumption you think you can state that the Church-Turing thesis has no truth-bearing?Finite string expressions that are not truth-bearers are rejected
as a type mismatch error for every formal system of bivalent logic.
Truthbearer(English, "This sentence is not true") is false.
Truthbearer(English, "This sentence is true") is false.
Truthbearer(English, "a fish") is false.
Truthbearer(English, "some fish are alive") is true. — PL Olcott
Assuming then it returns true for all true strings and false for all false ones, right? — ssu
So are you going here for the solution for the Entscheidungsproblem? Seems something like that. — ssu
So with this assumption you think you can state that the Church-Turing thesis has no truth-bearing? — ssu
The only issue that I am correcting is the notion of decidability.
— PL Olcott
A great thing! But tell, how have you corrected it? — tim wood
↪PL Olcott And this is just no correction at all. Near as i can tell from both reading your posts and your listed citations, all you have done is invoke an idea of a list of propositions that you have decreed "true facts." And there being no undecidable propositions among them - being excluded by you - you declare undecidability corrected. Unless you can mix in some sense, this stands both as nonsense and nonsensical — tim wood
Then what did Godel do and how did he do it? Or rather, inasmuch as he rigorously derives his undecidable proposition, on what basis do you claim it impossible? And now I insist on your using English unless you are using symbols to prove/demonstrate a point.then it is easy to see that epistemological antinomies and their negation cannot be derived from these true facts. — PL Olcott
Then what did Godel do and how did he do it? Or rather, inasmuch as he rigorously derives his undecidable proposition, on what basis do you claim it impossible? And now I insist on your using English unless you are using symbols to prove/demonstrate a point. — tim wood
Does it escape your notice that the theory, to be efficacious in the desired manner, has been enriched and has to be enriched? Or that the enriched thing - or any enriched thing - is not the same as the thing not enriched? — tim wood
Even if I'm just an amateur on these issues, I think here's a mistake.It is much simpler to see what Tarski did, Gödel hid the missing inference steps
behind Gödel numbers and diagonalization.
This is Tarski's formalized Liar Paradox
x ∉ True if and only if p
where the symbol 'p' represents the whole sentence x
https://liarparadox.org/Tarski_275_276.pdf
This is stated more simply as LP := ~True(L ,LP)
Tarski found out that ~True(L, LP) is true (in his meta theory) and
True(L,LP) is not provable in his theory and this got him confused.
This sentence is not true: "This sentence is not true" is true because
"This sentence is not true" is not true. — PL Olcott
Gödel isn't just coming up with the Liar paradox and "hiding" the missing inference steps behind Gödel numbers and diagonalization. Many people do think that Gödel has fallen into the trap of self reference and is talking about basically the paradox, but he isn't. — ssu
Let's stipulate that your "verbal model..," which is practically impossible and I suspect theoretically impossible, exists. I assume you mean that finite stings will be input, and that in every case the output will be, correctly, a T or an F. How will it work? — tim wood
Finite string expressions that are not truth-bearers are rejected
as a type mismatch error for every formal system of bivalent logic. — PL Olcott
what Gödel shows is that there's a true, but unprovable sentences. — ssu
Yet Milne has the gist of this: the problem here is that there indeed are true, but unprovable truths. — ssu
He doesn't actually show that and if he didn't hide his work we could see that he doesn't really show that. He doesn't even claim that, yet what he does claim is a little incoherent. G is true in PA yet not provable in PA. The way that we know G is true is that G is provable in meta-math. — PL Olcott
We can see that when we formalize the Liar Paradox correctly
LP := ~True(L, LP)
and not the clumsy way that Tarski formalized it :
x ∉ True if and only if p
where the symbol 'p' represents the whole sentence x — PL Olcott
:brow:He doesn't actually show that and if he didn't hide his work we could see that he doesn't really show that. He doesn't even claim that, yet what he does claim is a little incoherent. — PL Olcott
Interesting to talk about the same issue in two threads at the same time, but anyway...Milne is actually saying that there are some expressions that we know are true yet have no way what-so-ever to know that they are true. If an expression utterly lacks any criterion measure showing that it is true then it remains untrue. — PL Olcott
From your Stanford reference we have, "Let φ be the sentence, "φ is not true." That is, we have φ, simple enough and we need nothing else.
-------------
Now, in plain English, using φ, describe how your "system" works.
What you claim is that it knows what is true and what is not. I'm very skeptical, because of many arguments against this, and also not least because you have been singularly non-responsive through at least two threads and many posts. — tim wood
Ok, let's think about some of these expressions. And no, I haven't seen the actual Milne's paper, so I cannot say more when I have just the one link. (Is it free and obtainable by the net?) — ssu
The above shows just what the problem is when you "Cantor's diagonalization" or basically negative self reference.
So what your problem in using diagonalization? — ssu
From your Stanford reference we have, "Let φ be the sentence, "φ is not true." That is, we have φ, simple enough and we need nothing else.
-------------
Now, in plain English, using φ, describe how your "system" works. — tim wood
-----------------------In plain English:
"φ is not true."
What is φ not true about?
φ is not true about being not true.
What is φ not true about being not true about?
φ is not true about being not true about being not true...
Ok so φ NEVER gets to the actual point. — PL Olcott
Now, your predicate, lets call it P. is defined to return T or F for every string input. And that, apparently, based on finding a truth-maker of some kind for the particular string. But this either constitutes a definition of truth, or is purely an arbitrary distinction made by your program, in which case the P could stand for Procrustean predicate. Or in short, your T and F are exactly not T and F, but some approximation of them.My True(L,x) predicate is defined to return true or false for every
finite string x on the basis of the existence of a sequence of truth preserving operations that derive x from — PL Olcott
From reading your citation, it appears you're looking for a truth-maker for φ and not finding one. And from the reading, it is not clear that it needs one; i.e., φ is a truth-bearer. The problem, of course, is that if φ is true, then it is not true, and if it is not true, then it is true. — tim wood
It makes it undecidable - it appears you do not know what the words you use mean - and certainly not "inherently incorrect."That does not make True(L, φ) inconsistent. When True(L, φ) is false and True(L, ~φ) is false then φ is rejected are inherently incorrect. No sense moving beyond this point until after you totally get it. — PL Olcott
As described here, this is just a sorting program for testing inputs against a data base and dividing them into those that "agree" and those that don't, which you then call true and false. Which, as you present it and have answered questions about it, has zero interest or substance and too much nonsense.My True(L,x) predicate is defined to return true or false for every finite string x on the basis of the existence of a sequence of truth preserving operations that derive x from a set of finite string semantic meanings that form an accurate verbal model of the general knowledge of the actual world that form a finite set of finite strings that are stipulated to have the semantic value of Boolean true. — PL Olcott
It makes it undecidable - it appears you do not know what the words you use mean - and certainly not "inherently incorrect." — tim wood
For example, let your database, described above, be represented by, "The cat sleeps on the couch." You now test "finite" strings against your database, and those that pass are "true," those that don't, "false." And you can do that. But what has that to do with true and false, or knowledge of any kind, or anything undecidable? How does that show that Godel was mistaken or incoherent? Or that Tarski was confused? — tim wood
And any time you want to prove me wrong your keyboard is within easy reach. — tim wood
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