Comment on RDF/XHTML

At the WG F2F I expressed the (uninformed) opinion of an outsider
that the RDF/XHTML proposal is likely to open a can of worms --
and was asked to elaborate by email.

The problem I see is *NOT* that RDF/A is going to be seen as an
alternative to RDF/XML. In principle I have no problem with multiple
syntaxes optimized for different purposes. (In Topic Maps we have
two "official" syntaxes, XTM and HyTM, and two widely used unofficial
syntaxes (LTM and AsTMa=). This hasn't been a problem.) A cursory
look at the syntax even suggests that it has numerous "felicities"
compared to RDF/XML, but that is not the issue here.

The problem is that the goal seems to be to make RDF palatable and/or
usable by a "less sophisticated" audience, i.e. HTML users. I don't
believe you can expect less sophisticated users to use the full
power of something sophisticated without requiring them to become
more sophisticated themselves...

To me the most important use case for being able to embed RDF in an
HTML document is to allow authors to annotate *that document*, such
that other applications (based on RDF or Topic Maps) can harvest the
metadata and merge it with other metadata. Examples would be
"last-modified-at" and "author".

To do this, all that is necessary is the ability to insert simple
property-value pairs into the document. It shouldn't even be necessary
to specify the subject, since that is a given (it is the document
itself, or some section of it, depending on where the metadata is
specified).

Allowing users to add *more* than this, to annotate the annotations,
as it were (for example specifying an author's affiliation), is to
invite duplication, redundancy, and inconsistency.

If an author has written two documents, would it be considered good
practice for his/her affiliation to be given in both? One would hope
not, but this is the kind of situation that we invite by offering
the full panoply of RDF expressivity in XHTML.

Unfortunately it seems that the mandate of the TF was to support
something more than simple metadata. In my opinion this was a mistake.


Steve

--
Steve Pepper <pepper@ontopia.net>
Chief Strategy Officer, Ontopia
Convenor, ISO/IEC JTC 1/SC 34/WG 3
Editor, XTM (XML Topic Maps 1.0)

Received on Monday, 1 November 2004 17:14:08 UTC