I have exactly the same concern with the proposed schema.org Identifier as with the bibframe Identifier. 

If <http://bowker.com/identifiers/isbn/9780553479430> is an identifier for a resource X,
and <http://www.worldcat.org/oclc/38264520> is also an identifier the same resource X,
and <http://bowker.com/identifiers/isbn/9780553479430> is a schema:Identifier, 
and <http://www.worldcat.org/oclc/38264520> is a schema:Book,
then resource X is both a schema:Book and a schema:Identifier at the same time.

Which is clearly nonsense.

Basically ... don't do that. Please. 

Rob



On Fri, Jul 11, 2014 at 11:16 AM, Mark K. Ehlert <[log in to unmask]> wrote:
Young,Jeff (OR) <[log in to unmask]> wrote:

UmljaGFyZCB3cm90ZSB1cCB0aGUgaHR0cHM6Ly93d3cudzMub3JnL2NvbW11bml0eS9zY2hlbWFi
aWJleC93aWtpL0lkZW50aWZpZXIsIGJ1dCBJIGRvbid0IHJlbWVtYmVyIG11Y2ggZGlzY3Vzc2lv...


For those who can't read Jeff's response, here it is:

Richard wrote up the https://www.w3.org/community/schemabibex/wiki/Identifier, but I don't remember much discussion of it.

The abandoned "info" URI effort leaves me skeptical that non-HTTP URIs can be systematically described in general. I'm also skeptical that individual identifiers of any kind need to be described inline with instance data.

http://info-uri.info/

Jeff


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Rob Sanderson
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