Theories of Semantics on theWeb - Social Semantics: The Search for Meaning on the Web - page 83

Chapter 4
Theories of Semantics on the Web

Meaning is what essence becomes when it is divorced from the
object of reference and wedded to the word.
W.V.O. Quine (1951)

4.1 The Identity Crisis

How can agents determine what a URI identifies? To use a word more familiar to
philosophers, how can anyone determine what a URI refers to or means? On the
pre-Semantic Web, a URI trivially identifies the hypertext web-pages that the URI
accesses. On the Semantic Web, a whole new cluster of questions, dubbed the
Identity Crisis , emerges. Can a URI for the Eiffel Tower be used to refer to the
Eiffel Tower in Paris itself? If one just re-uses a URI for a web-page of the Eiffel
Tower, then one risks the URI being ambiguous between the Eiffel Tower itself and
a particular representation of the Eiffel Tower. If one gives the Eiffel Tower qua
Eiffel Tower its own URI, should that URI allow access to any information, such
as a hypertext web-page? In the realm of official Web standards, the jury is still
out. In the specification of RDF, Hayes notes that “exactly what is considered to be
the 'meaning' of an assertion in RDF or RDF(S) in some broad sense may depend
on many factors, including social conventions, comments in natural language” so
unfortunately “much of this meaning will be inaccessible to machine processing”
such that “a full analysis of meaning” is “a large research topic” (Hayes 2004).
The comment in the RDF Semantics specification glosses over a huge argument.
Unsurprisingly, the reason there is no standardized way to determine the meaning
of a URI is because, instead of a single clear answer, there is a conceptual quagmire
dominated by two positions in the development of RDF. The first position, the
direct reference position , is that the meaning of a URI is whatever was intended
by the owner. The owner of the URI should be able to unambiguously declare and
communicate the meaning of any URI, including a Semantic Web URI. In this
position, the referent is generally considered to be some individual unambiguous