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Re: [lojban] negating connectives



In a message dated 8/12/2001 10:00:34 AM Central Daylight Time,
a.rosta@ntlworld.com writes:


How do we negate a connective so as to mean "this connective yields a
false/wrong truth table, but its truth-reversal does not necessarily yield a
true/correct truth table"?
For example, if I know that p iff q, I would like to be able to somehow say
that I know that it is false/wrong that p and q.


I'm not sure I follow, since the example doesn't seem to be an example of
what I took the general case to be. But to try to deal with the general case
first, I suppose that {na'e} would work {p ina'eje q} (I'm not sure the
grammar works here) "p somehow other than 'and' q"  I'm not at all sure what
this would *mean*; in one sense it does not even seem to require even that
one or the other is in fact false, though another sense does seem to require
at least this.
Now, for the example.  If you know that p iff q and you know that p and q is
false, then presumably what you know is that neither p nor q is true.  But I
suspect that this is not getting to what you want.

<In asking the first question, am I falling victim to the fallacy of
construing connectives as possible-worlds operators, so that the answer
to my question needs to be sought amid the logic of possible-world
operators rather than the logic of connectives?>

Maybe that is the problem.  I would not make much sense of the original
question about totally particularized claims (place, time, world, whatever
fixed) only about relations between fairly general cases, thunder na'e e
lightning, say -- they don't just cooccur, but what the best way to spell out
the range of possibilities is may not be perfectly clear.  So, in that sense
(the sense of a truth table, in effect) this is a possible worlds question,
it presupposes a range of possible situations involving the same components.  
For a single case, there is only one of these possibilities realized and it
can either be spelled out or left as the denial of any incompatible case.