A panel on whether or not ontology is needed to achieve a collective vision for the semantic web was held on Tuesday at the International Semantic Web Conference (ISWC 2009) near Washington, DC. For most of the panelists the question was rhetorical. But there were a few interesting points made, including that machine learning of ontology is one extreme of a spectrum that extends to human authoring of ontology (however authoritative or coordinated). Nobody on the panel or in the audience felt that the extreme of human authored ontology was viable for the long-term vision of a comprehensively semantic and intelligent web. It was clear that the panelists believed that machine learning of ontology will substantially enrich and automate ontology construction, although the timeframe was not discussed. Nonetheless, the subjective opinion that substantial ontology will be acquired automatically within the next decade or so was clear. There was much discussion about the knowledge being in the data and so on. The discussion had a bit of the statistics versus logic debate to it. Generally, the attitude was “get over it” and even Pat Hayes, who gave a well-received talk on Blogic and whom one would expect to take the strict logic side of the argument, pointed out seminal work on combining machine learning and logic in natural language understanding of text.
David Karger of MIT’s AI lab challenged the panel from the audience by asserting that the data people posted on the web is much more important than any ontology that might define what that data means. This set off a bit of a firestorm. There was consensus that data itself is critically important, if not central. For the most part, panelists were aghast at the notion that spreadsheets of data would be useless to computers unless the meaning of its headings, for example, were related to concepts defined by reference to ontology those computers understood.
With respectful deference, the panel and audience yielded. Sir Tim Berners-Lee took the floor. Continue reading “Sir Tim Berners-Lee on Ontology”