On Sat, Mar 13, 2004 at 02:11:48AM -0500, Andrew Archibald wrote:
> On Fri, Mar 12, 2004 at 05:39:32PM -0800, Robin Lee Powell wrote:
[...]
> > [1]: I'm pretty sure xorxes is right on this, but I'm going for what I
> > think you meant.
>
> That is indeed what I meant; I read the CLL and didn't realize this
> was such a subtle issue.
>
> Clearly {noda viska node} is equivalent to
> {noda node zo'u da viska de}.
> But does this translate to
> "There is no X, there is no Y, such that X saw Y"
> or
> "There is no X such that there is no Y such that X saw Y"?
The way to write the former in predicate logic is with only one negation.
~ExEyVxy
So that's how you do it in lojban: {noda de zo'u da viska de}, or
equivalently something like {naku da viska de} or {da na viska de}.
> The first is what I meant; the second is not. The CLL has an exactly
> parallel case:
>
> #3.3) ro da ro de zo'u da prami de
> # For-every X, for-every Y : X loves Y.
> # Everything loves everything.
>
> Of course, {ro} is not {no}; in this example it doesn't matter which
> is chosen. I think, upon more careful reading, that the correct
> interpretation of <quantifier X> <quantifier Y> zo'u <predicate> is
> <quantifier X> such that <quantifier Y> such that <predicate>. Is
> this correct?
Yes. Every quantifier creates a scope which applies to all the
following quantifiers. Quantifier scopes is one of the least
understood portions of the language---people frequently forget that
{lo} creates an implicit scope just like da. Some scope issues are
also unresolved/broken in CLL.
It's a very frequent error among lojbanists (you'll see it on irc
a lot) to confuse quantification if they have a negation. "roda"
is not the same as english "everything"; after naku you probably
want "su'oda", etc.
> Can I say "There is no (X,Y) such that X sees Y"? I can't understand
> what the CLL has to say about "grouping of quantifiers" to tell
> whether this is what they do (although jbofi'e doesn't seem to think
> so).
I think you can use a termset (cf. example 7.5 in chap 16).
{noda ce'e node viska}, or something like that.
But I'd just stick with what I suggested above: {da na viska de}
or {naku da de viska}.
--
Jordan DeLong
fracture@allusion.net
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