Re: An argument against modus ponens

On Sep 4, 5:14 pm, John Jones <jonescard...@xxxxxxx> wrote:
You accept, do you not, that the function "if.." (and/or the function
"then..") immediately (if you like) launches us into a context where "if
P" yields P as true or not true.

No, dumbass. NObody accepts that.
You are stressing 1 half of a duality. I was stressing the other
half.
But we don't have to fight about it; the fact that it REALLY IS a
duality means that
BOTH ways are equivalent. You, unfortunately, probably do not even
know what
the duality is BETWEEN, so I will tell you.

The duality is between declarative (mine) and procedural (yours).
My version ignores time; everything is static all at one time, and for
all time.
Your version HAS time; in your version, If P then Q means P comes
FIRST and Q
(maybe) comes SECOND. It WORKS both/either way, but they are NOT
the SAME
way.

I said that "nobody accepts" your way, but I also said that both ways,
including yours,
work. The reconciliation of that apparent contradiction is that you
are NOT fluent
in YOUR OWN way. IF you were, you would've known to say that, on
your side of
the fence,
"if.." (and/or the function
"then..") immediately (if you like) launches us into a context where "if
P" yields P as true

is ALL that is happening. THE WHOLE purpose of "if/then" is to
EXCLUDE that
half of the models where P is false. Those are explicitly being
RULED OUT by
"if P". The whole purpose of saying "If P" is to launch us into a
subsequent context
where P is GUARANTEED to be true and where, therefore, its falsity
will entail any and every most ridiculous absurdity.



And, as it happens, if P is true, then Q follows.
But my point is that whether Q follows or not, or even whether "then"
always follows "if", or is a necessary adjunct to the grammar of "if",
an "if .." proposal sets up a context of truth and falsehood.

NO, DUMBASS. RATHER, the context of truth and falsehood
SETS UP THE POSSIBLITY OF "if/then", AND of 15 OTHER binary boolean
functions. It is MEANINGLESS to say "if" until AFTER you have
PREsupposed
a boolean context.


Which is sort of what you yourself meant, actually, but you are so bad
at this that you don't even understand which way causal arrows go.
.

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