Subject: Re: [lojban] "knowledge as to who saw who" readings

From: And Rosta <[email-masked]>
Date: Wed, 10 Oct 2001 18:19:17 +0100

Is there some way we can characterize this middle ground, narrower than extensional, broader than intensional, so that we can all get a sense of what it is and how to recognize it? 

As I see it, we need to be able to express -- through different constructions -- both a narrowish intensional reading and a broadish extensional reading, which seems to me (on the basis of superficial thought) to be handlableby truth-conditions.

I take your point about your version of Set-of-Answers, but it doesn't seem
to help us in the more general problem of reporting the beliefs of others.
The problem is: how do I describe John's belief when I know its truthconditions but not its particular propositional and intensional form?

--And.

>>> <[email-masked]> 10/10/01 05:19pm >>>
In a message dated 10/9/2001 9:07:53 AM Central Daylight Time, 
[email-masked] writes:

> I continue to feel much disquiet about these issues. I think we have to be
> able to describe the beliefs of others in terms of truth-conditional 
> equivalence,
> so that "J believes that not either p or q" is equivalent to "J believes 
> that
> not p and not q", for instance. Without this ability, many claims we would
> want to make about what others believe would be stronger than we would
> want, and also subject to other problems that we would often want to
> avoid (notably, what counts as sufficient fidelity, when a bridi represents 
> a 
> belief?). We need both intensional and extensional descriptions of beliefs.
> 

Actually, we need something different from either, narrower that extensional, 
broader than intensional. Extensional lets in everything that happens to be 
coextensive with what you want on this world, including all the things wanted 
but also an indeterminate amount of junk -- even vyapti lets in all the stuff 
that happens to fit the same s-t coordinates, so allows in a lot of 
irrelevant microscopic and atomic stuff. Intensions on the other hand deal 
with only definitional equivalence,as it were, not the incidentals of this 
life that might be allowed to count in some cases of knowing, say.  
(Incidentally, the "not either p or q" - "both not p and not q" passes the 
intensional test as well as the extensional.).

One of the initial advantages of set-of-answers theory (my version, I think 
not xorxes' completely) is that it provides for this middle ground in the 
notion of an answer to the question. This advantage dims somewhat if you 
then try to unpack that notion in rigorous categories, for it is inherently 
pragmatic and Gricean, depending upon the background knowledge of all 
involved, the presuppositions of the speaker and probably the listener (to a 
lesser extent), and some operational notion of epistemic imperatives as 
appled to the particular case (is this where knowing a=b and Fa means you 
ought to know Fb?). Still, it does meet the purpose and some unpacking can 
be done in aprticular cases at elast. So, that is some progress from the dead 
ends of pure extension and pure intension, which are doomed to empirical 
failure.