Wow :)  Thanks for that, Dan!  

On Mon, Jul 26, 2021 at 11:43 AM Dan Brickley <> wrote:

On Mon, 26 Jul 2021 at 11:58, Jan Dittrich <> wrote:
I would be very interested in Wikidatas Relation to Cyc on one hand and the semantic Web on the other.

this isn’t written down in one place well, yet

Here is one strand of history, emphasising from Cyc via Guha’s later work on MCF.

CycL inspired Apple MCF, which got XMLified by Tim Bray when Guha took it Netscape. June ‘97 it was submitted to W3C by Netscape. It combined with requirements from W3C content labeling work (PICS), where there was interest in adding more decentralized expressivity (eg to support Dublin Core and other schemas being combined in one “label”), complex structures and datatyped property values, aka Signed PICS labels and PICS-NG. While PICS and PICS-NG had an s-expression based syntax, RDF (like the 1997 iteration of MCF) went with XML. At the time XML was being invented by stripping SGML down into something that might suit the Web. Microsoft submitted XML-Data to W3C mid 97 too (as well as later a revision, breaking W3C etiquette). XML-Data shared some goals with RDF but not its graph data model. RDF and other usecases led to XML Namespaces being an important thing. As XML popularity grew, RDF was under pressure since it didn’t engage much with the SGML heritage. The RDFS WG launched just after the RDF Model + Syntax spec was announced at Dublin Core’s conference in Finland. This being the “browser wars” era both RDF and RDFS were under huge pressure to be completed quickly. RDFS included a small subset of the schema-defining machinery from MCF. The RDF M+S WG produced an RDF recommendation in Feb 1999 but RDFS was left in limbo, in part because the XML community were wary of being forced to build XML Schema on top of it. Meanwhile from 1998 a small but enthusiastic community started to build around RDF - experimenting with query languages, databases, integration with inference engines, APIs etc., alongside continued support from Netscape who used the technology heavily for everything from RSS feeds, sitemaps, “whats related” annotation services, open data (dmoz) dumps, to their own browser’s internal data source APIs (xul templates, bookmarks, mail, ..). On the standards track, W3C management backed off from RDF work to reflect the concerns of its membership, who tended to much prefer XML. Meanwhile the US military research agency DARPA had been persuaded by an academic turned staffer (Jim Hendler) who had worked on similar early technology (SHOE, PIQ) that they should fund research to standardize a DARPA Agent Markup Language. A DAML / W3C collaboration led to the RDF-oriented W3C team at MIT receiving DARPA funding to continue the work area that had not engaged the XML-centric interest of W3C’s membership (ie Advisory Committee). Alongside this, RDF/S had engaged the interests of European researchers working around logic-based KR languages, eg f-logic, description logics etc., resulting in DAML (US) and OIL (description logic EU research project outcomes) collaborating via adhoc transatlantic committee to produce DAML+OIL, a first draft of a more complicated language that sat on top of RDF. The W3C MIT DARPA funding supported a “Semantic Web Advanced Development” activity that operated in the grey around of W3C’s “non member-funded activity”, and which served in particular to bring DAML+OIL into W3C as new work item. This next phase of RDF work at W3C was broadly in line with the RDF roadmap and expectations from the 1997 Metadata Activity, but rebranded “Semantic Web” to reflect several considerations. Firstly that RDF was clearly more powerful and expressive than a simple metadata format might need. Secondly, by this point RDF was pretty unpopular in several contexts - and seen as draining staff resources and attention from W3C membership priorities (XML, Web Services, etc.). Renaming from RDF allowed a fresh start. Calling it Semantic Web tied into Tim-BL’s interest and writing in the area, had more “visionary” feel, allowing for a message that it was a longer term investigation, therefore not a competitor to XML Schema, SOAP, Xquery and so on. So now we had PICS and MCF having mutated into RDF/S for graph data, and then simultaneously a rebranding of the exercise as Semantic Web, with a big dose of “futuristic” and “researchy”. Conferences and journals and such started to appear, initially with much more focus on the “semantics” part, rather than the “web”. This was the cause for the second great half-hearted renaming, which grew from the growing split between those of us who were in this for web-based data sharing, integration, feeds, sitemaps, rss, foaf etc and so on, and those who were more “semantics first”, with a passion for finding efficient subsets of Description Logic. Around the mid-2000s the earlier experimental RDF query languages solidified into SPARQL, which was broadly in the “data access” side of the community. This is another place that the Cyc and MCF heritage showed up, since most practical RDF systems had a notion of source or context attached at the triple of graph level, corresponding to the notion of “layers” in MCF (and very loosely with cyc contexts). So this kind of takes us to the time when we had rdf/s, owl, skos, sparql … and things like dbpedia and the lod cloud were refining the data-linking “hypertext rdf” work we’d started in the FOAF project, with a TimBL-fueled passion for every entity being given a URI that can serve up RDF when dereferenced. A good amount of public open datasets were published this way, although applications and usage tended to lag. This brings us to the era of rich snippets, Google acquiring Freebase, renaming it Knowledge Graph and then stepping back from the role that Wikidata was more effective at filling…

Ok that was a giant biased brain dump, but i think mostly true, and about 25 years underdocumented history squeezed into a paragraph 



Am Fr., 23. Juli 2021 um 01:57 Uhr schrieb Denny Vrandečić <>:
Hi Thad,

Thanks for asking the questions, and thanks Tobi for the pointers. Man, what a lengthy post it was.

I understand that the post answered most of your questions. I think that it is entirely possible to layer a prototype semantics over Wikidata, just as the DL semantics have been layered over it. I don't remember if such work has been done before.

Regarding ISO 5964, I think I probably have looked through it at some point, but I don't remember it anymore. SKOS has certainly been a stronger influence, and obviously OWL.

I hope that helps with the historical deep dive :) Lydia and I really should write that book!


On Sat, Jul 10, 2021 at 3:00 PM Thad Guidry <> wrote:
Tobi - That blog post 3 is very helpful.  It shows that Denny and I think alike and agree on everything. :-)  His dislike for strong classification.
Which is part of my basis, to allow weak relations much more.  And use them.  But how to allow them, and I think the only way is through properties based on the Data Model currently.
There are many ways, and SKOS is one way to allow expressing weak relations and we already have some good support with existing properties like P4390 mapping relation type and a host of others.

Denny and I also fear the same things, like not having a flexible enough system to describe our complex world that doesn't always fit into strict rules.  Which is kinda why I've always liked
because of it's non-transitivity which allows much flexibility and as he and I would say... avoid "Barbara". :-)
Which is pretty much summarized in

Sorry for all the SKOS links but semantic relations helps to describe human knowledge.  How a system represents or portrays semantic relations is where choices are made or have been made.  And I think the right choices were definitely made.
Overlaying SKOS and the Wikidata properties that sprinkle it into the data model is useful, but I've always been kind of reluctant to do that...probably for the same reasons Denny might give?  Choices between allowing "semantic accuracy" versus "semantic flexibility".  But I think systems like SKOS provide both.  Perhaps it could be argued that OWL provides much less. :-)  Still all KOSs provide great use when they fit well.  How they can fit over Wikidata, as I said, is probably only through properties at this late stage of design and that's fine with me!

Still, my main focus is and always will be trying to add human knowledge about concept relations into Wikidata to help machines, to help us.  (the "edges" that humans quickly can deduce in seconds, but still to this day can sometimes take machines days or weeks to figure out).

My usage and help to Abstract Wikipedia and Wikidata later on will primarily be around the mapping of relations ... where a lot of the possibilities have already been described years and years ago at the very bottom of this long page:
inter-KOS mapping relationships  <-- very last row, 3rd column

Denny -  were you part of or lightly influenced by ISO 5964 through Germany ISO DIN or not .. that also would be good to know.

On Sat, Jul 10, 2021 at 3:17 PM Tobi Gritschacher <> wrote:

It would be nice to have a place to look with a link to a page in the Community portal that says "History of Wikidata's design and early collected meetings, notes, design documents, recordings"

Might not answer your concrete question, but here are some (very) early blog posts by Denny. They are still a nice read. :) 

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