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Re: Why do we name nodes and not edges?

From: Aidan Hogan <aidan.hogan@deri.org>
Date: Wed, 25 Jul 2012 17:01:21 +0100
Message-ID: <50101851.5060302@deri.org>
To: semantic-web@w3.org
Steve,

Sorry, I think I probably misinterpreted your mail. When you used:

http://example.com/edge/123456

I guess you meant it to be an "instantiation" of:

http://example.com/edge


I missed this first time round.

Apologies,
Aidan

On 25/07/2012 16:47, Aidan Hogan wrote:
> Steve,
>
> If I understand Melvin's point, in RDF, edge:123456 is the URI of a
> property used to label the edge, not the edge itself.
>
> Analogously, you don't identify a class-instance by it's class URI.
>
> An edge is between two things. It might be directed and it might be
> labelled. In RDF it's both.
>
> Hence, the edge would encapsulate the full triple, including source
> (subject) and target (object) nodes, as well as the label (predicate).
>
> Cheers,
> Aidan
>
> On 25/07/2012 16:18, Steve Harris wrote:
>> Nothing stops you from giving edges a unique URI, infact I think I've
>> worked on systems that did that.
>>
>> e.g.
>>
>> <foo> <http://example.com/edge/123456> 1 .
>> <http://example.com/edge/123456> a rdf:Property .
>> ...
>>
>> - Steve
>>
>> On 2012-07-25, at 16:07, Melvin Carvalho wrote:
>>
>>> Sorry if this topic has been covered before, but I have a question
>>> based on the axioms of the web, in particular:
>>>
>>> *Axiom 0a: Universality 2    Any resource of significance should be
>>> given a URI.
>>> *
>>> In this case we consider the web to be a directed graph (of nodes and
>>> edges), where a *node* corresponds to a *resource* but edge does not.
>>>
>>> We are encouraged to make nodes universal by giving them a URI.
>>>
>>> Why dont edges get the same treatment, ie encouragment to give it a
>>> (universal) name.  Is it even practical?
>>>
>>> I know there's such thing as reification but that seems to be
>>> unpopular (maybe before my time).
>>>
>>> I'm just curious as to whether this seems asymmetrical, that nodes are
>>> seemigly treated in one way, and edges in another?
>>
>> --
>> Steve Harris, CTO
>> Garlik, a part of Experian
>> +44 7854 417 874 http://www.garlik.com/
>> Registered in England and Wales 653331 VAT # 887 1335 93
>> Registered office: Landmark House, Experian Way, Nottingham, Notts,
>> NG80 1ZZ
>>
>
>
Received on Wednesday, 25 July 2012 16:02:12 UTC

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