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On Mon, 22 Jul 2024 20:17:15 -0400, in articleI am establishing a new meaning for
<3fb77583036a3c8b0db4b77610fb4bf4214c9c23@i2pn2.org>, Richard Damon wrote:>[...]
On 7/22/24 8:11 PM, olcott wrote:
I think a better example might be Goodstein's theorem [1].*No stupid I have never been saying anything like that* If g and>
~g is not provable in PA then g is not a truth-bearer in PA.
What makes it different fron Goldbach's conjecture?
* It is expressible in the same language as PA.
* It is neither provable, nor disprovable, in PA.
* We know that it is true in the standard model of arithmetic.
* We know that it is false in some (necessarily non-standard) models
of arithmetic.
* It was discovered and proved long before it was shown to be
undecidable in PA.
The only drawback is that the theorem is somewhat more complicated
than Goldbach's conjecture -- not a lot, but a bit.
[1] <https://en.wikipedia.org/wiki/Goodstein%27s_theorem>
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