I think the right venue for resolving some of the philosophical questions of
identity and URIs belongs in the IJCAI conference workshop and not on the TAG
agenda.
Many TAG and other semantic web discussions about identity and reference ask
questions about equality, identity, counting, and distinguishing "resources",
for example, " Is the resource identified by URI X the same as the resource
identified by URI Y?"
"How many resources does a URI identify?"
My perspective is that these questions are not well formed. Equality and
countability are mathematical operations. The space of "resources" is not a
set, has no well-defined notion of "identity", and there is no way, in general,
of determining "equality".
There is a notion of "inequality" but to the extent you can ask:
"Is the resource identified by URI X the same as the resource identified
by URI Y?"
generally you can determine "No" or "Maybe". In some circumstances, if X is
string-equivalent to Y, the answer might be Yes.
Since you cannot, in general, determine equality of two resources identified by
two different URIs, counting them or arguing "sameness" doesn't work.
