"We don't know that the earth is round"
and
"We believe that the earth is flat" [...]
The differences are so easy to point out that I don't see the sense in asking about it. — TonesInDeepFreeze
Why is
q -> Kq
being stated?
— TonesInDeepFreeze
Because p -> Kp was stated. — InPitzotl
No one believes that as a generalization for all q.
— TonesInDeepFreeze
Apparently some people do. It's an antirealist position; the p doesn't exist until it's proposed, and it isn't true until you say it is, or some such thing. — InPitzotl
The topic is about propositions, but more formally about sentences. — TonesInDeepFreeze
the intended interpretation of the 'K' operator is that of knowing the existence of a propostion or sentence, but rather it is that the proposition or sentence is known to be true. Ignoring that point leads to incoherence. — TonesInDeepFreeze
Probably none; this was stated by TMF, and the view appears to be held by Olivier5 (haven't caught up here; you've likely already met).What specific quotation or reference is given by anyone (other than a flagrantly errant poster) that p -> Kp? — TonesInDeepFreeze
this was stated by TMF — InPitzotl
One my choose to hold that a proposition does not exist until it is has been expressed. But even if we restrict to the set of propositions that have been expressed, we have not vitiated Fitch's argument.
It is not the case that for all propositions p that have been expressed we have p -> Kp. Therefore, as Fitch shows in the proof, it is not the case that for all propositions p that have been expressed we have p -> LKp. — TonesInDeepFreeze
Fitch's paradox is about true propositions.
— TheMadFool
I know. I'm extending it to false propositions as well. Sue me. — Olivier5
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