[topicmapmail] multiple Source Locators

[Murray Altheim]

Kal Ahmed wrote:
> On Wed, 2004-09-01 at 10:14, Jan Algermissen wrote:
> 
>>Kal Ahmed wrote:
>>
>>>On Wed, 2004-09-01 at 07:36, Lars Marius Garshol wrote:
>>
>>>>You can do this, but you can also use URIs the way we use subject
>>>>identifiers. RDF doesn't define what the semantics of the reference
>>>>are.
>>>
>>>Right, so you do it by using them in a context defined by a predicate.
>>
>>Not to start an argument here, but the above is actually wrong. By
>>design, the semantics of a URI reference are always the same. You cannot
>>use a URI in a different contexts to refer to different things. Not
>>if you intend to be 'on the Web'.
>
> Context is everything - you are talking about one context, your "on the
> web" context. I am talking about a different context. I am saying that I
> can introduce semantics that define a different context. Both views are
> correct, but are not necessarily interoperable. 

Kal,

Unless I've misinterpreted the various RFCs incorrectly, or perhaps
one of the various W3C documents that relate to this subject (more
likely), the URI *itself* is context-free. You can, like any word
or phrase, utter it within a context. But the actual definition of
what a URI means is not altered by context. As you say, people can
introduce contexts to alter the semantics, but that doesn't alter
the semantics of the URI itself. The semantics are bound to the
context, not the URI.

If that makes any sense.

Murray

......................................................................
Murray Altheim                    http://kmi.open.ac.uk/people/murray/
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK               .

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