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Re: TECH: nec (Was: QUERY: quantifier scope & cumk

Iain answers john and me:

> "nibli" is closer to the sentence operator Nec, which
> in Quine takes a quoted sentence, than to the standard modal operator nec.

Don't you both mean {sarcu}?

No I don't think so.  'sarcu' is about contingent necessity,
nibli about logical necessity. I'm not sure that either is
completely appropriate (each has another argument) but
I am sure that we are talking about logical rather than
contingent necessity.

nibli nib     ni'i necessitate                               x1 logically necess
action/event/state x2 under rules/logic system x3

sarcu         sa'u necessary                                 x1 is necessary/req
 uired for continuing state/process
x2 under conditions x3; (cf. nitcu)

I'm not familiar with the particular system(s) you're referring to,
and I may be misunderstanding what you're saying, but surely it *is*
possible to reason about the argument of nec - you just have to be
careful to apply the appropriate rules.

Of course it is.  But the rules are not just a couple of extra
rules of inference. Look what's going on in John's example:

>         nec 5 < 9
>         9 = the number of planets
>         nec 5 < the number of planets

It's substitution of equal terms that has broken down - as far as
I can remember you have to go into intensions and extensions to
fix this. (Your example works because 'nec' makes the intension
a constant function).