My blog entry was mostly about grass roots or informal ontologies, which I think will succeed where the "Semantic Web" will fail, not so much in delivering the goods to its paying benefactors (such as DARPA and other large government and corporate entities), but in actually having any real impact on the Web as used by the Rest of Us.
The Web community has always developed its own technologies, almost in spite of the W3C, and this is only reinforced by the open source movement. There's no particular reason why RSS or Atom or other new Web technologies need to be based in RDF, it's just a convenient (cough) XML graph syntax. GXL or XTM would do just as well, maybe even better. I've long believed people's enthusiasm for RDF is simply a misplaced enthusiasm over graphs. To those long bound to hierarchies and tree structures, graphs seem very cool, like the Che Guevara of mathematical structures. They're more like the way of the world inside and outside our heads. Some people get very passionate about such things. Others like to watch golf on TV, so go figure?
Anyway, apart from my normal ranting I closed with mention of two issues near and dear to my own research: identity and context. I note that univers immedia has a reference to Chris Welty and Nicola Guarino, both of whom have done some excellent work on the former. Patrick Brézillon has for a number of years been leading conferences that focus on the latter, and maintains a web page about his work on context. While much of the Semantic Web stuff I find almost nonsensical in its almost complete absence of issues of epistemology, identity and context, these guys have been doing some very important work for many years. I don't think we could underestimate the important of Brézillon's conferences in pushing the issue of context into the mainstream.
One of the things that I'm pretty convinced of is that everything is contextualized, even identity (I won't quote the first two chapters of the Tao Te Ching). So where in the Topic Maps models we always talked about the notion of some kind of fixed identity point around which we hung Topic characteristics, if that identity is itself fluid (i.e., contextualized by any of a myriad of factors, human and not), it doesn't exactly break the model, but it makes it a lot more complex, perhaps more capable of modeling real life. For those of you who speak XTM natively, we'd just need to add an optional <scope> element to the content model of <subjectIdentity>. But there's probably a way to do this without mucking with the XTM syntax.
I've been digging around in the philosophical/epistemological literature (e.g., , [2/3], [4/5], ), trying to find that Copernicus-in-the-bathtub experience (no, not that one, the other one) on how identity and context mesh. It seems sometimes the more I dig the more complicated the issue becomes, and unfortunately my research domain isn't theoretically in philosophy (at least that's what my advisors keep advising me — they hope I'll actually finish my dissertation one day). The pile of books keeps getting higher.
The Penumbra said to the Umbra, "At one moment you move: at another you are at rest. At one moment you sit down: at another you get up. Why this instability of purpose?"which kinda sums up my own experience lately...
"Perhaps I depend," replied the Umbra, "upon something which causes me to do as I do; and perhaps that something depends in turn upon something else which causes it to do as it does. Or perhaps my dependence is like (the unconscious movements) of a snake's scales or of a cicada's wings. How can I tell why I do one thing, or why I do not do another?" -- Chuang Tse, (trans. Lin Yutang)