Re: JSON-LD Telecon Minutes for 2011-07-04

On 7/5/11 7:09 AM, Manu Sporny wrote:
> Topic: Formal Definition of Linked Data
First assertion about Linked Data reads:
Linked Data is used to represent a directed graph .

Sorry, but that's back to front, at best.

A directed graph used to represent (describe) an object can be 
constructed in such a way that subject name, subject attributes, and 
subject attribute values take the form of de-referencable URIs.

In the case of Linked Data, specifically, a URI de-references to a 
representation of its Referent. It does this because an Object has 
Identity distinct from its Representation. Thus, an Object has a Name 
that's distinct from the EAV/SPO graph pictorial that delivers its 
description (representation). Naturually, on the Web (as is the case 
with a computer's local OS), said representation exists as the content 
of a Resource at a location (Address).

Of course, you don't have to accept my definition of Linked Data. But 
note this, bar different turn of phrase, I've just outlined the very 
essence of TimBL's original Linked Data meme prior to the regressive 
tweak that added "(RDF* and SPARQL)" to its later revision. The day 
"(RDF* and SPARQL)" are dropped from the meme or described as 
implementation details is the day that meme returns to its GOLDEN status 
IMO.

At this juncture, the JSON-LD definition of Linked Data is inaccurate.

You can make graphs that aren't Linked Data purveyors. Thus, don't 
conflate graphs and linked data, let alone application of the linked 
data concept to a global data space such as the WWW. The specific use of 
URIs as part of graph construction is integral to what linked data is 
about.

 From RDF to JSON-LD conflation remains a problem. Conflation ultimately 
breeds confusion.

The pieces of the puzzle:

1. Graphs -- an effective data structure fine grained data representation
2. de-referencable URIs -- critical data structure tapestry (remember a 
URI isn't implicitly de-referencable, the URL subClassOf URI is)
3. Resources -- data (collections of eav/spo triples) containers 
accessible from addresses.

Current list of conflation examples:

1. Resources -- everything is a resource meme is inaccurate since it 
dangerous ignores perception media (WWW and Real World are related but 
distinct media)
2. Graphs -- RDF is the only mechanism for graph representation or that 
graph means RDF rather than RDF being an option for graph based data 
representation
3. Linked Data -- to the RDFer Linked Data and RDF are one and the same
4. JSON-LD -- Linked Data is either a subset of RDF or its used to 
represent directed graphs.

Sincerely hoping these comments are digested. I have but a single goal: 
kill off conflation so we can make progress re. InterWeb scale Linked 
Data without forcing syntax or data serialization formats on anyone. 
Openness isn't as easy as folks assume. To be truly open you have to 
invest heavily in the significant costs associated with choice.


-- 

Regards,

Kingsley Idehen 
President&  CEO
OpenLink Software
Web: http://www.openlinksw.com
Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca: kidehen

Received on Tuesday, 5 July 2011 08:45:53 UTC