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Re: RDF and the Test of Independent Invention

From: Melvin Carvalho <melvincarvalho@gmail.com>
Date: Fri, 29 Apr 2016 17:16:00 +0200
Message-ID: <CAKaEYhKgjWhKA=xcj14pWpFXM7LAUePJoGcvg4iYb3=Gk4jKQg@mail.gmail.com>
To: Pat Hayes <phayes@ihmc.us>
Cc: Semantic Web <semantic-web@w3.org>
On 28 April 2016 at 03:13, Pat Hayes <phayes@ihmc.us> wrote:

> On Apr 27, 2016, at 3:49 PM, Melvin Carvalho <melvincarvalho@gmail.com>
> wrote:
> The test of independent invention [1] asks "If someone else had already
> invented your system, would theirs work with yours?"
> Now imagine if someone had invented RDF (lets call it RDF-L) but with one
> slight difference.  You are allowed to have literals in the predicate
> position.
> FWIW, the RDF semantics can handle this without significant change.

Ah ha, thanks!

Well, I suppose that answers the question.  RDF "v.next" passes the TOII
(at least this one).

> Is there a way that RDF could be made to work with RDF-L.
> Define "work with". RDF is valid RDF-L, and the RDF semantics generalizes
> to RDF-L without significant change, so the only hard problem is going to
> be getting RDF-L syntax through an RDF parser. That would require some
> rewriting of code, to be sure, or inventing a convention (and persuading
> everyone to adopt it) which disguises predicate-position literals as IRIs.
> The only really hard part of this is getting everyone to agree on such a
> convention.

OK, so perhaps in future, this problem will be solved, if people move to
accepting predicates as literals.  But maybe that wont happen too.  I am
unsure here.

> This is more than a theoretical question, it has practical implications.
> The "triple" model which ties key value pairs to a subject, could be
> thought of as a type of Entity Attribute Value (EAV) [2] model.  There are
> many examples of EAV models that allow literals in the "second" position.
> JSON springs to mind.
> Does RDF pass the TOII?  If not, can we work out a way to make it do so.
> After some thought my current favourite idea is to make the following two
> equivalent:
>     "predicate" <--> urn:literal:predicate
> Not sure I like the *equivalence* as it seems to require all existing RDF
> to be rewritten using URNs, which I would ask God to forbid except it isn't
> going to happen so there is no need for prayer. But perhaps you don't mean
> this.

Yes, well equivalence may be the wrong term here.  What I would be thinking
about is some kind of stop gap to use in the short to medium term.

One thing occurred to me.  Perhaps urn:string is more appropriate than

As you say inventing a convention would help with interoperability.  So is
this mailing list a good place to start?

If urn:string isnt the optimal name, what else could we use?  A new URI
called string:

Or simply just make http URIs for each use case and have the free for all
that we have today?

> Pat
> Thoughts?
> [1] https://www.w3.org/DesignIssues/Principles.html
> [2]
> https://en.wikipedia.org/wiki/Entity%E2%80%93attribute%E2%80%93value_model
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Received on Friday, 29 April 2016 15:16:29 UTC

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