- From: Garret Wilson <garret@globalmentor.com>
- Date: Fri, 27 Jul 2007 08:50:34 -0700
- To: Henry Story <Henry.Story@Sun.COM>
- CC: Semantic Web <semantic-web@w3.org>
Henry Story wrote: > > _:123 xsd:integer "123" . > > Which is to say that there is a thing, which has relation xsd:integer > to the string "123". > my guess is that the relation xsd:integer, is inverse functional and > functional. But I disagree with this. Does this thing also have a relation xsd:integer to the string "one hundred and twenty three"? The string "123" is an identifier---no more no less. The *only* relationship the string "123" has to _:123 is eg:oneOutOfTheManyWaysHumansRepresentThisValueUsingUnicodeCharacters. > > Now I am not sure if in this case the blank node refers to itself. I > suppose some (Bertrand Russle for example) would say it refers to the > set of sets of size 123, just as 2 refers to the set of pairs, and 3 > refers to the set of triples. But I am not sure how one should think > of it in rdf. Funny---30 minutes ago having breakfast I was thinking of exactly the same point, because it illustrates again how RDF uses literals for various unrelated cases. Integers are completely different things than URIs, somewhat different than dates, and parallel to base 64 binary. RDF literals would also be appropriate for Java enum types, such as MyColor.RED or PowerSetting.FULL. In short, literals are used in RDF for everything we can think of that can easily be represented by a string. The string is simply an identifier. It refers to the resource, and that's the only relationship it has to the resource. So I would rewrite your example: _:123 rdf:type xsd:integer . > > > _:123 morse:intcode "_...." . I'm find fine with that (assuming that _:123 revers to the value 8 ;) ). We could also have: _:123 rdf:canonicalIntegerLexicalForm "123" . (Exaggerating the name for emphasis) But the point is that "123" is not the resource. It's just one representation of it. > > > [] morse:intcode "_...." ; > xsd:integer "123" . I think you mean the same thing that I say above, but it's confusing, because in XML Schema xsd:integer is a type. If you mean rdf:canonicalIntegerLexicalForm or something, then fine. I want to reserve xsd:integer to be the object of the rdf:type predicate. Garret
Received on Friday, 27 July 2007 15:50:47 UTC