Abstract: The Identity Crisis, the argument about what exactly a "resource" is and what can a URI actually identify, nearly de-railed early Semantic Web efforts. Should a URI for a web-page about the Eiffel Tower be the same as a URI for the Eiffel Tower itself? We will trace two distinct positions, the first being the logicist position of Hayes, which in the tradition of Russell and Tarski holds that the semantics of the Semantic Web are entirely (un)constrained by the formal semantics, and the direct reference position of Berners-Lee, which in the tradition of Kripke and Putnam, holds that a URI unambiguously identifies one thing. We present a formal ontology in OWL-DL for modelling these issues. With the resolution of this problem by the W3C, the Linked Data initiative took off, but now the Semantic Web has a new problem: too many URIs for what appear to be the same thing! We present an analysis of this problem by running a corpus of queries from a major search engine against the Linked Data Web, and present a simple solution in the tradition of late Wittgenstein for enabling convergence on the social meaning of a URI.
Harry Halpin is a Ph.D. student in the School of Informatics at the University of Edinburgh, whose advisor are Henry S. Thompson, a member of the W3C Technical Architecture Group (TAG), and the philosopher Andy Clark. He is a member of the W3C Semantic Web Co-ordination Group and former Chair of the W3C GRDDL Working Group.