|
|
Rupert wrote:
Aatu Koskensilta wrote:
Tbe first incompleteness theorem is usually expressed something like the
following
For any extension T of Robinson arithmetic we can effectively find a
sentence G_T, s.t. G_T is true and undecidable in T iff T is
(1-)consistent.
"If" surely, not "iff"?
To make it "iff", the condition would have to be that T does not prove
its own inconsistency, which is weaker than 1-consistency.
You're right, of course.
--
Aatu Koskensilta (aatu.koskensilta@xxxxxxxxx)
"Wovon man nicht sprechen kann, daruber muss man schweigen"
- Ludwig Wittgenstein, Tractatus Logico-Philosophicus
|
|