random

Lulu of the Lotus-Eaters mertz at gnosis.cx
Sun Jun 3 16:54:03 CEST 2001


"Alex Martelli" <aleaxit at yahoo.com> wrote:
|"Even given (a powerful army) I could not (defeat Napoleon)".
|Do you read this as "having a powerful army IMPLIES I
|cannot defeat Napoleon"?  This doesn't sound right to me.
|Surely it's "NOT (having a powerful army IMPLIES I can
|defeat Napoleon)"?

Perhaps I should give up, since there me little progress to be made.
But conditionals just seems too interesting and subtle to leave to the
Boolean logicians.

Let's leave all the quanta and Laplacian fantasies aside, and just look
at defeating Napolean.

    (1) Even given (a powerful army) I could not (defeat Napoleon)

The very first thing I would claim about this conditional is that there
is an important implicature to be noted:

    (2) Someone claims that (given a powerful army...)

The statement only makes sense given the background claim.  Really, what
(1) says is not firstly -anything- about the comparative truth values of
its antecedent and consequent; rather (1) disputes the imagined
interlocutor of (2).

The next thing I would claim about (1) is that, conversationally, it
must be taken as true, or at least -arguably- true.  Moreover, the
sentence contains a clear negative epistemic attitude towards its
antecedent.  Among other things, (1) asserts:

    (3) I do not have a powerful army

It provides no new information--and indeed wholly misses the structure
of the statement--to launch into an investigation or dispute about
whether the speaker of (1) has a powerful army.  A stipulation is not
a bare fact.

The final note I would make is that (1) specifically authorizes
consideration of statements with a common consequent with (1).  While
not affirmatively asserting any such statement is true, it strongly
suggests that not every such statement is false.  So for example:

    (4) But given (time to wait out his death) I could (defeat Napolean)

should be given consideration as plausible, according to the urging of
(1).

Needless to say, the material conditional captures little of this... not
matter where you want to put the NOT in the affair.

Yours, Lulu...




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