Re: An argument against modus ponens

On Sep 10, 2:40 pm, John Jones <jonescard...@xxxxxxx> wrote:
Objects don't have properties of truth and falsehood.

They do IN LOGIC, DUMBASS.
The whole enterprise IS ABOUT truth and falsehood.
Of course, in first-order logic, we do generally distinguish between
"first-class" objects AND SENTENCES, and it is the latter that
must have truth or falsehood, while the former usually don't.
But in the extended sense in which YOU are using "object"
(you are calling P an object, whereas people WITH a brain would
call P a proposition -- that' s *why* "P" is chosen as a name for it),
propositions and/or boolean variables MUST have truth-values.

.

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