they seem to be assuming that they're demonstratively referring to the real object in the external world,
rather than the subjective object of their own perceptions, that other people happen to share to some degree.
( Moon Girl Technologies horrendous beanbag, Tue 16 Jun 2009, 19:54, archived)

Exactly. But why?
I can draw up two situations in which one has demonstrative reference and the other doesn't, but otherwise they are exactly the same. A language which demonstratively refers and one which doesn't are indistinguishable from the point of view of the subject.
( Comma, Tue 16 Jun 2009, 19:57, archived)

Because they want to.
What are the alternatives to demonstrative reference?
( Moon Girl Technologies horrendous beanbag, Tue 16 Jun 2009, 19:59, archived)

The alternative would be either a language which has no meaning, which isn't the case,
or a language in which we don't refer to objects in the external world, but only to our images of them.
( Comma, Tue 16 Jun 2009, 20:04, archived)

I think we form a concept of objects in the external world from our images of them,
and then refer to that, because two people might have completely different views of an object, but they still know what each other are talking about.
( Moon Girl Technologies horrendous beanbag, Tue 16 Jun 2009, 20:07, archived)

This all sounds like you're going to start talking about Magritte.

( Druid, Tue 16 Jun 2009, 20:03, archived)