Re: The need for RDF in Linked Data

Plus, if you don't have RDF strictly within the definition of Linked Data,
what else do you have? Just any generic data that is linked? Isn't that the
Web (not Linked Data)?


On Mon, Jun 17, 2013 at 7:35 AM, David Booth <david@dbooth.org> wrote:

> [Followup to semantic-web@w3.org please]
>
> -------- Original Message --------
> Subject: The need for RDF in Linked Data
> Date: Mon, 17 Jun 2013 01:26:35 -0400
> From: David Booth <david@dbooth.org>
> CC: semantic-web <semantic-web@w3.org>
>
> There seems to be some persistent misunderstanding about the
> role of RDF in Linked Data, as evidenced by comments like
> the following:
>
>   "RDF is just one implementation of Linked Data"
>
> If Linked Data is intended to support the goal of the Semantic
> Web, then unless the Semantic Web is re-architected with a new
> foundation, RDF is *essential* to Linked Data -- not optional,
> and not merely one potential choice among many.  the reason is
> that the Semantic Web critically relies on the use of *both*
> a standard universal identification convention (URIs) for its
> vocabulary, *and* a standard universal information model (RDF)
> for making statements.
>
> To understand why a standard universal information model
> is important, one must think back to the central goal
> of the Semantic Web.  the goal is to enable computers
> to do more useful things for us: to enable them to
> find, share, combine and make meaningful use of web data.
> http://www.scientificamerican.**com/article.cfm?id=the-**semantic-web<http://www.scientificamerican.com/article.cfm?id=the-semantic-web>
> This means that a client application processing some web data
> should be able to follow links in that data to find more data
> that it can *also* meaningfully use.  the only way that can be
> achieved is by using a standard universal information model.
> otherwise the client application will have no reliable way to
> properly interpret that new data.
>
> For example, suppose the client application dereferences
> a URI and obtains a comma-separated-values (CSV) document.
> unless the client application knew how to interpret that file,
> it would not be able to make meaningful use of that data.
> it would be stuck at a dead end.  but if the document were
> expressed in a standard universal information model, then
> the client application would at least be able to understand
> what statements the document was making.  and if the client
> application did not already understand the vocabulary --
> i.e. the meanings of the URIs -- then it could recursively,
> using Linked Data techniques, dereference the URIs to discover
> their meanings.
>
> Why does RDF need to be the standard universal information
> model?  not because it is perfect, but because *some* standard
> universal information model is needed, and that is the one
> that was chosen, just as URIs were chosen to be the standard
> universal identification convention.  furthermore, because RDF
> is syntax independent, a document does not have to *look* like
> RDF in order to be interpreted as RDF. for example, GRDDL allows
> arbitrary XML to be interpreted as RDF.  The enormous value
> of JSON-LD is that it provides a more web-developer-friendly
> syntax than ever before for a universal information model.
>
> why couldn't other sufficiently powerful information models
> achieve the same Semantic Web goal just as well, and be used
> in addition to RDF?  Because that would fragment the web.
> instead of one web we would have many webs, each one its own
> walled garden, and that is not be Semantic Web goal.  without a
> shared information model, client applications would not be
> able to meaningfully combine the data from those walled gardens.
>
> I do not expect anyone to take my word for this. All I ask is
> that you think about it.  Because if you do, the conclusion
> is unavoidable: if Linked Data is going to support the goal
> of the Semantic Web (without re-architecting it), then Linked
> Data MUST be based on RDF.
>
> this obviously begs the question: *should* Linked Data support
> the goal of the Semantic Web?  that certainly was TimBL's
> intent when he coined the term and wrote his article about
> it: http://www.w3.org/**DesignIssues/LinkedData.html<http://www.w3.org/DesignIssues/LinkedData.html>(but I
> continue to be amazed at how differently different people seem
> to understand that article, so I imagine there would still be
> some who would disagree even with *that* point.)
>
> *I* certainly think that Linked Data should support the goal
> of the Semantic Web.  and I think that JSON-LD -- *because*
> it will be such a web-developer-friendly RDF syntax (assuming
> a few small issues are resolved, so that it really *is* an
> RDF syntax) -- will be a big step forward.
>
> If the term Linked Data is "hijacked" by a broader population
> to mean *any* sort of data that is linked -- not necessarily
> RDF -- then this will be a major loss to the Semantic Web
> community, because it is very hard to come up with simple ways
> to communicate the essence of the Semantic Web.  The Linked
> Data meme has been extremely helpful.  If the RDF component
> is lost, we will have lost the best meme we have ever had for
> explaining the Semantic Web.`
>
> David
>
> [Followup to semantic-web@w3.org please]
>
>
>
>
>