Then you'd argue incorrectly — TonesInDeepFreeze
It's a valid argument only if you allow that A --> ~A is of the form A-->~B. — Hanover
This is where we disgree. — Hanover
If P is false, then P -> ~P is true. — TonesInDeepFreeze
It's where you disagree with the definition of 'modus ponens'. — TonesInDeepFreeze
If P is false then if P is true then it is true that P is true is a contradiction pretty plain and simple. — Hanover
You're confused. I'm not "equating" A -> ~A to A -> B.
Let P and Q be metavariables over formulas. Then modus ponens is any argument of the form:'
P -> Q
P
therefore Q
Instantiate P to A. Instantiate Q to ~A. There is no restriction against such an instatiation.
So
A -> ~A
A
therefore ~A
is an instance of modus ponens. — TonesInDeepFreeze
We're in disagreement that P--> Q = P --> P. The former is a conditional, the latter a tautology. — Hanover
You cannot substitute P and Q to be — Hanover
maintain logical equivalence — Hanover
A -> ~A = ~A — Hanover
A->~B is not reducible to ~A. — Hanover
A-->~A is not logically equivalent to A --~B. — Hanover
It's like saying A+A = 4 and since it's generic — Hanover
You somehow got in your head a wrong notion. — TonesInDeepFreeze
The absurdity is that you think this a question of logic and not definition. — Hanover
No meaningful logical conclusion can follow from a contradictory conditional that assets the proposition and its negation can occur simultaneously. — Hanover
Modus ponens "is the rule of logic stating that if a conditional statement (“if p then q ”) is accepted, and the antecedent ( p ) holds, then the consequent ( q ) may be inferred." — Hanover
If your conclusion is not true, you can't offer MP as the basis of it being true because it's not. — Hanover
No, it's the DEFINITION of 'modus ponens'. — TonesInDeepFreeze
Modus ponens doesn't require that a conditional is not contradictory, nor that the "major" premise (which must be a conditional) is not contradictory, nor that the "minor" premise (which might or might not itself be a conditional) is not contradictory, nor that the premises together are not contradictory — TonesInDeepFreeze
And it is intellectually shameful... And risible...
Get outta here with that bot garbage! — TonesInDeepFreeze
How pathetic... — TonesInDeepFreeze
Meanwhile, you need to not litter a philosophy forum with confused, misinformational, and malformed bot garbage. — TonesInDeepFreeze
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