Re: I have a trouble with The RDF Model

At 02:15 PM 11/26/00 -0600, pat hayes wrote:
>I have a slightly more basic trouble with the "RDF Model". I really cannot 
>understand what it is supposed to be a description OF.  Are these 
>'triples' to be considered syntax or interpretation? Since RDF has an 
>XML-ish syntax which is quite different (it involves many angle brackets 
>and quotation marks, for example), the 'triples' are apparently not the 
>syntax. So I presume that they are intended to be part of the 
>interpretation of the syntax, ie the semantics of RDF is defined in terms 
>of abstract entities called 'triples'. But if that is so, then Stefan's 
>reply to Seth, above, doesn't make sense, since obviously semantic 
>interpretations aren't the kind of thing that can be located on websites, 
>or which have 'sources' in this sense, or which are assigned truthvalues; 
>and Stefan seems to refer to the model theory *of* the triples, rather 
>than to the triples as constituting the model theory. So I am left 
>completely confused about the meaning of RDF, as indeed I have been ever 
>since first meeting it. I have been assuming in the DAML discussions that 
>it is basically simply a syntactic specification (possibly the ugliest 
>ever devised by any human being, but let that pass) without any actual 
>semantics. However, some people seem to think that it has a semantics. Can 
>anyone point me to a specification of a model theory for RDF? (Just to 
>save time, there isn't one in: 
> )

[and also, in an other message]

>Talking of what 'belongs to' something is just muddying water which is 
>already so murky as to be hard to see through. Would it be possible for 
>you, or someone connected with RDF, to give a precise specification of 
>what exactly *is* the syntax of RDF? Until someone does, none of this 
>discussion is really worth having, since it is too imprecise to make any 
>rational sense.

I have come to think that sometimes "one man's semantics is another's 
syntax".  In the world of syntax we have symbols and construction 
rules.  In the world we live in there are the "real" objects with which we 
interact.  I think there are in-between layers that try to build constructs 
that are somehow "closer" to the "real" world than the elements they're 
built from.

I think this means that, in your terms, the RDF model (triples, etc.) is 
just another syntax.

But, at another level, they may be closer to modelling the "real world" 
than the character-based syntax of raw XML.


Graham Klyne                       Content Technologies Ltd.
Strategic Research              <>

Received on Wednesday, 29 November 2000 16:07:47 UTC