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Re: RDF's challenge

From: Pat Hayes <phayes@ihmc.us>
Date: Tue, 11 Jun 2013 16:59:16 -0500
Cc: public-lod@w3.org
Message-Id: <F5B70923-0B77-4557-BB82-86914501A1B0@ihmc.us>
To: Kingsley Idehen <kidehen@openlinksw.com>

On Jun 11, 2013, at 11:18 AM, Kingsley Idehen wrote:

> On 6/11/13 11:56 AM, David Booth wrote:
>> On 06/11/2013 10:59 AM, Kingsley Idehen wrote:
>>> [ . . . ]  many RDF advocates
>>> want to conflate Linked Data and RDF. This is technically wrong, and
>>> marketing wise -- an utter disaster.
>> I have not heard RDF advocates conflating Linked Data and RDF, but maybe you talk to different RDF advocates than me.
>> AFAICT, the vast majority of RDF advocates know that Linked Data is RDF in which URIs are deferenceable to more RDF, but RDF is not necessarily Linked Data, because RDF itself does not require URIs to be dereferenceable.
>> David
> RDF isn't the defining characteristic when speaking about Linked Data outside the RDF community. It is much more palatable outside of the RDF community to loosely couple Linked Data (the concept) and RDF (a framework) which enables the construction of powerful Linked Data that's endowed with *explicit* human and machine-comprehensible entity relationships semantics.
> Why? Because you don't build friction with folks that are already familiar with similar concepts albeit described using different terminology.
> The key is to build bridges rather than impede their construction by enforcing world views in the most inflexible way.
> If someone indicates to you that the letters R-D-F don't work for them, for whatever reason, what's wrong with triangulation to the same destination when it's the fundamental concept that matters, not the labels that we slap on them at specific times in our innovation continuum?

Because while the labels don't matter, to understand that these are all the same under the hood *does* matter. And if we keep re-branding it to suit some perception of fashion, we will keep reinventing the same wheel (but with a slightly different axle or bearing, so it can't be re-used on the same vehicles.)

Let me put the point differently: if someone rejects a useful tool because its called "RDF" instead of "Foodle", without knowing squat about RDF or how it works, why should we care what that idiot does or doesn't do? There are plenty of more reasonable, intelligent or simply better people out there who don't react to ideas with the intelligence of a frog. Lets try talking to them for a change. 

> RDF and the Entity Relationship model [1] outlined by Peter Chen in his 1976 dissertation are linked, conceptually and technically.

RDF is also linked, in the same way and with about as much justification, to Codd's relational model, Prolog, SQL, virtually any graph-based representational formalism (UML, anyone?), semantic nets, about a dozen AI-KR notations dating from the early 1970s and still further to classical Tarskian relational logic back to the 1940s. But don't stop there. Almost all serious knowledge or data representational formalisms use the foundation model of entities standing in relationships, and data expressing facts about those relationships. There are books tracing the history of this idea back to medieval European scholastics such as Duns Scotus, about a thousand years in Europe, and then via Islamic scholars back another thousand years to Aristotle. 

As for actual historical influence, as opposed to re-inventing the wheel for the ten thousandth time, as far as I know RDF was basically a simplified version of the semantic net idea coming from what is known as logic-based AI/KR work (and OWL has its roots in description logics, pioneered by the KL-ONE project at Bell in the early 1980s), and certainly the RDF sematnics was directly built on classical Tarskian logical ideas (with a slight twist coming from ISO Common Logic). AFAIK, the Chen ER model was not involved in this at all. But as I say, this idea of everything being entities and realtionships has probably been re-invented more times that you or I have drawn breath. None of these ideas are even remotely new. The fact that binary relationships are enough to encode aribtrary relationships (of any arity) has been known since CSPeirce's writings in 1887; I learned that trick as an undergraduate. The ideas of blank nodes, and what we now call graph syntax, also come directly from Peirce. 

> That association is very powerful and extremely useful in situations where your audience suffers from R-D-F reflux.
> RDF is useful, but it (like all innovations) has genealogy. That genealogy is just as important as the innovations it adds to the continuum.

If you are going to do genealogy, do it thoroughly. 


> Links:
> 1. http://bit.ly/YTdz3N -- The Entity-Relationship Model -- Toward a Unified View of Data  (note: page 34) .
> -- 
> Regards,
> Kingsley Idehen	
> Founder & CEO
> OpenLink Software
> Company Web: http://www.openlinksw.com
> Personal Weblog: http://www.openlinksw.com/blog/~kidehen
> Twitter/Identi.ca handle: @kidehen
> Google+ Profile: https://plus.google.com/112399767740508618350/about
> LinkedIn Profile: http://www.linkedin.com/in/kidehen

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Received on Tuesday, 11 June 2013 21:59:44 UTC

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