Subject: Re: [lojban] A or B, depending on C, and related issues

From: [email-masked]
Date: Fri, 10 Aug 2001 11:20:39 EDT

In a message dated 8/9/2001 9:19:07 PM Central Daylight Time, 
[email-masked] writes:

> >The best simplification I could find in a dash was ~(Q&R) &(P => QvR) ,
> >which, while shorter, is markedly less informative when talking about
> >depndencies.
> 
> Actually, that reduction fails when P, Q, and R are false.
> (It gives true, should give false.)
> 
Yup! One problem with working at a dash when you have lousy handwriting 
(never mind P anQ, it's T and F that are the problems).

<The actual reduction, funnily enough, turns out to be (Q xor R),
independent of P!

What's more, this other one:

[(P iff Q) and (not P iff R)] xor [(not P iff Q) and (P iff R)]

also reduces to the same thing: (Q xor R).

This makes sense, because the truth value of "Q or R depending on P"
cannot depend on the truth value of P, since we are not specifying
what the dependency is. This fits in very nicely with the Pkau
interpretation, which might be:

   Pkau => (Q xor R)>

I would have taken the reduction as evidence that this was a totally 
inappropriate rendition of "Q or R depending on P" since it says that Q or R 
regardless of P (or anything else). But then, I don't understand what all of 
this has to do with indirect questions exactly -- or with whatever keeps 
being called indirect questions while being neither (unless "indirect" means 
"vague").  

I suppose "{xn} depends on {ym}" means something like "there is a set of true 
conditionals (not necessarily truth-functional, if that bothers people) whose 
antecedents are each a member of {ym} and whose consequents are members of 
{xn}" and then some details about completeness and exclusiveness -- which 
might vary from case to case, as might the details of how the conditionals 
run. The vaguer terms ("what's for dinner," "what's in the icebox," "what 
the weather is") just cover these lack of details, while guaranteeing the 
gneral (though possibly vacuous) claim.
The only connection I can see between all this and questions is the 
possibility that 
expressions like "what's in the icebox" stands for a set of answers (claims 
in this case, not propositions).