Re: The king of france is ...

On Apr 18, 7:07 am, "Jesse F. Hughes" <je...@xxxxxxxxxxxxx> wrote:
holden_o...@xxxxxxxx writes:
In general (x)(Kx -> Wx) is not valid.
But, ~ExKx -> (x)(Kx -> Wx), is valid for any K and any W.

Yes, ~ExKx -> (x)(Kx -> Wx) is a tautology.

In the particular case in this thread:

~ExKx & (~ExKx -> (x)(Kx -> Wx)) -> (x)(Kx -> Wx).
And, both premisses are true, therefore (1) (x)(Kx -> Wx) follow
logically by Modus Ponens.

Yes, given ~ExKx, it follows that (x)(Kx -> Wx).  Surely, I never
suggested otherwise.

From the start, my only comment was that you misused the term
"tautology", not that the general thrust of your argument was
mistaken.

It is clear to me that tautology does indeed apply to monadic
predicate logic expressions.

Why do you think otherwise?


--
Jesse F. Hughes

Mama:           "We'll stop [eating] when your stomach says 'stop'."
Quincy (Age 4): "Oh, come on.  They don't talk."

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