The cardinal rule at the first Dublin Core meeting way-back-when was Thou Shalt Not Conflate Syntax and Semantics. A rule honored more in the breech than in observance perhaps, but it emphasizes the importance of separating these two fundamental facets of communicating structured information. We were right about this… almost. The missing part of the picture was a sound underlying data model.
We knew what we were trying to say, we thought we knew how to say it. How hard is it to describe the basic characteristics of a resource, after all? Title of resource is…. Creator of resource is…. We even spoke about the initiative in terms of grammars and evolving pidgin languages (simple, emergent grammars). We hobbled along with only a vague common understanding – a model implicit in the aggregate projects using Dublin Core, propagated through imitation, nowhere formally specified.
It isn't though we didn't try. Early attempts to arrive at a formal data model were fraught
with contention and even acrimony. Difficult
But the chickens come home to roost. The lack of a formal model led to a plethora of non-interoperable systems, crippling one of the foundation principles of the Initiative. It took 10 years for DCMI to finally evolve and adopt a formal model, and one might wonder whether simple exhaustion was a factor in its ultimate acceptance. It will be a long time before this model channels practice sufficiently to bring the many flavors of DC closer to the goal of sharing metadata across systems, let alone across various other metadata frameworks.
The Dublin Core Abstract Model, led by Andy Powell and Pete Johnston, and later attracting the efforts of Mikael Nilsson in the cause of bridging the DCMI framework with that of IEEE LOM, is a hybrid distillation of ideas gleaned from library practice and the Semantic Web’s cornerstone technology, RDF. It reflects insights of emerging Web practice (the use of URI’s as persistent identifiers, for example), and embraces lessons learned from a decade of early metadata adopters.
Yesterday afternoon at DC-2006, Diane Hillmann presented a summary of progress (and… surprise… contention) associated with the RDA effort, what most people understand as the international revision of AACR2. From my own uninformed perspective, it appears that this effort suffers from much the same problem that we have had in the Dublin Core – a data model implicit in years of practice and rule-revision on top of rule-revision, resulting in a focus on the minutia of rules rather than being guided by formal principles of description.
The Web has forced us all out of isolated communities of practice and into the Internet Commons. Certainly the practice and topography of librarianship is changing out from under us. As we struggle under the stress of these changes, it is perhaps predictable that legacy systems such as cataloging practice will change even more slowly. The RDA effort recognizes the importance of updating our profession to fit more comfortably into the Internet Commons. If we are to achieve anything like the interoperability we hope for, we will need common structural models. If the effort devolves to simply unraveling existing rules and rewinding the yarns, we will fall short of the integration we need to support our future. The successes and failures of the DC community in its own modeling struggles can be useful… and reusable. I gather that the Joint Steering Committee has sought consultation with representatives of the IEEE LOM metadata community as well as with DCMI. It would be fitting if the DCMI could return some value to the community that has provided so much of the insight that has motivated its own progress.
Mikael Nilsson’s exhortation is on the mark. Less talk about metadata sets, and more talk about models. It is both difficult and important to get this piece right.
Image: DC-2006 welcome reception