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RE: Working without being ambushed by Ambiguity

From: Larry Masinter <masinter@adobe.com>
Date: Wed, 30 Jan 2013 08:01:07 -0800
To: Graham Klyne <GK@ninebynine.org>
CC: Pat Hayes <phayes@ihmc.us>, Tim Berners-Lee <timbl@w3.org>, David Booth <david@dbooth.org>, "www-archive@w3.org" <www-archive@w3.org>
Message-ID: <C68CB012D9182D408CED7B884F441D4D1E401FD19F@nambxv01a.corp.adobe.com>
> For me, there are several intertwined issues here, in no particular order:
> - context
> - ambiguity
> - vagueness
> - sound inference
> - modalities (? - I mean conflicting or differing interpretations in a common
> discourse)
> 
> What we *have* in the present model theoretic approach is sound inference.
> In particular, with RDF, the idea that the RDF merge of two (or more) graphs is
> true under exactly the interpretations that make the original graphs true.  I
> think this is a key necessity (but not sufficiency) for combining and remixing
> data on the web through automated processing, and of itself represents an
> important step forwards from what we had before.  I'm reluctant to let that go.

I think you can only keep "sound inference" after you've done some kind of
Trust transformation, where the semantics of responses to requests are
Initially posited to not be available for combining and remixing before they
have been explicitly accepted as trustworthy.    

I see no point in distinguishing between ambiguous assertions and untrustworthy
ones, and I like having a model where trusting is an explicit part of the interface.


> Along with this, I think vagueness is somewhat covered by a Quine-like appeal
> to consideration of statements that people broadly accept as true, if one doesn't
> get too hung up on exactly *what* is denoted by individual terms, just
> accepting that they have denotations that satisfy certain properties.
> 
> I think that ambiguity of the kind that permits Herbrand style models is
> something that we should just ignore - it seems to me that trying to exclude
> this kind of ambiguity in the formal structures leads to the kind of tar-pit
> we've been wading in.
> 
> I *think*, BICBW, the last two points somewhat reflect what Tim was trying to
> say in his original "without being ambushed by Ambiguity" - so to that extent
> we
> may agree.
> 
> But what we don't have is a satisfactory, easy to follow story that covers
> context and modality (if "modality" is the right word to use here).  Which would
> (should) extend to topics like "slander".
> 
> Here, I fear we're being let down by the RDF working group.  They have agreed
> a structure, RDF Datasets, that is capable of encoding such ideas, but seem
> unable to come to a consensus on how to provide semantic underpinning for using this
> structure.  IMO, *any* semantic underpinning would be better than none -
> without it, we're back in the mess we had figuring reification last time round.  (What I
> was hoping for is *not* a definitive "this is what datasets mean", but a
> framework within which one could construct semantics for datasets without
> fear that the ground would later shift.)  There have been several proposals, and at
> least two that I'm aware of in the life of the current RDF group - including
> Pat's RDF as context logic - any (or most) of which could serve.
> 
> (Personally, I liked the proposal that was made, and apparently rejected, a
> month or so ago
> (http://www.w3.org/2011/rdf-wg/wiki/TF-Graphs/Minimal-dataset-
> semantics).  I
> have the impression, maybe wrong, that Pat's context logic approach was a bit
> more constrained, but still flexible enough to support a useful range of
> modalities.)
> 
> Given this much, we would have some basis for actually talking about (or
> representing) some of the tricky issues that are so hard to discuss in the
> current "one interpretation to rule them all" view of RDF (and URIs).  We could
> propose structures that capture belief, provenance (which I come to see can
> itself be highly contextual), disagreement, debate, conditionality, and so much
> more.  Maybe then we also have a framework for encoding the theory of
> speech
> acts, etc?
> 
> If we have a way to represent and talk about contextualization, then I think the
> whole issue of a URI having different interpretations in different contexts (or
> applications) is something we can accommodate.  That is, it allows us to set out
> without a presumption of global meaning, yet still exploit the commonalities
> we can observe.   Within RDF as we currently have it, we're forced to go "out of
> band", and that makes it hard to really understand each other's difficulties.
> 
> ...
> 
> As for "attrition", I don't think we're dealing with a belligerent enemy here.
> 
> But I do feel like I'm on the rough edge of the grindstone here.  For the most
> part, I can ignore this stuff in my daily work with RDF:  99% of the time it
> seems it just doesn't matter.  But I fear if we don't build on sound foundations
> then sooner or later things will start to crumble.  I care if that's the case,
> but a lot less than I care about a lot of other things, so my forays into this
> arena will be of limited energy.  Maybe that's for the best.
> 
> #g

The problem with "for the most part, for 99% of the time, I can ignore
trust" is that you don't know which 1% of cases you can't. And if you
can't distinguish in advance between situations where you can trust
the results and situations when you can, then you basically have to 
distrust everything. 
Received on Wednesday, 30 January 2013 16:01:52 GMT

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