- From: Emery, Pat <pemery@grci.com>
- Date: Thu, 12 Apr 2001 21:50:31 -0400
- To: "'www-rdf-logic@w3.org'" <www-rdf-logic@w3.org>
I think we are trying to make the Web work better. The current bread pudding definition of our improvement includes URI's. If I have a sentence that includes in it a URI, you will be hard pressed to tell me the meaning of the sentence without knowing what the URI means. If the sentence is completely constructed of URI's that will make it even harder. If the semantic web is about meaning and the technological solution defining the semantic web includes the use of URI's, we as a community better figure out a way to determine the meaning of a URI given that URI. Pat Emery -----Original Message----- From: Dan Brickley [mailto:danbri@w3.org] Sent: Thursday, April 12, 2001 2:37 PM To: Aaron Swartz Cc: pat hayes; RDF Logic Subject: Re: A plea for peace. was: RE: DAML+OIL (March 2001) released: a correction (long rant; triggered by rather than targetted at Aaron's msg) On Thu, 12 Apr 2001, Aaron Swartz wrote: > pat hayes <phayes@ai.uwf.edu> wrote: > > >>> All objects? There are objects which have no name in any human > >>> language. > >> That doesn't prevent you from giving them one. > > That doesnt prevent it, but there might well be circumstances which > > do prevent you from giving them one. Obviously we can, and often do, > > refer to things that we cannot possibly give a name to (since we > > cannot identify them), eg as when we say that a beach contains > > hundreds of billions of grains of sand, each consisting largely of > > silica. It is (literally) impossible to give a name to every grain. > > Is it really impossible? Hmm, how about we say that I define: > > http://aaronsw.com/games/2001-04-12/sand_n > > where n is the number of the grain of sand on the shore of Lake Michigan, > USA, numbered depth first, from top to bottom and left to write currently > existing at the precise moment in time that I click send on this message. > Now I've given them all names. Sure, it may be extremely, extremely > difficult (I'm not sure that it is actually impossible) to go from one of > these names to the actual grain of sand, but that does not mean that I have > not given them all a name. This is getting far too silly! The problem is that URIs are a social fiction that've worked well enough for people, but when you look closely we don't have a clear model of naming. So it doesn't do any good to proclaim alice-in-wonderlandishly that some URI names some set of real world entities. URIs were a neat hack that made web version 1.0 work extraordinarily well, but sometimes people on www-rdf-interest seem to treat them as magic. They're not, and the asignation of URI names to things is just as philosophically problematic as any other kind (ie. very, when you dig into the detail). The nice thing about URIs is they're easy to parcel out, there's plenty of them, and they help us do joins in databases. But if I say that http://danbri.org/123541 names the 14th thought that Pat Hayes had today, where does that get us. Have I assigned meaning to a URI? What about http://danbri.org/345234234 which I now proclaim as referring to "the number you first thought of". Silly. URIs are a convenient fiction; I don't find much value in debating how many URIs one can assign to grains of sand. The vague notion of "giving a URI" to something isn't something we're going to find easy to formalise. URIs, we say, are a special kind of name, used on the Web. As such they share characteristics with other ways of naming. Philosophers have killed a *lot* of trees chasing this particular holy grail. There are no uncontroversial theories of reference: the connection of names to the world is a deeply social, ill-defined business. Rummage through the Philosophy of Language, or of Science, literature. [quick google search: eg see http://ruccs.rutgers.edu/~joncohen/reference_syllabus.html ] A great many smart people have written a great many books and papers presenting and defending theories of how names and the world are connected. *And we have no way to judge which (if any) of them got it right*. Or whether the notion of a 'correct' theory of reference is a healthy goal in the first place [Stephen Stich has written nicely on this; don't have ref to hand]. All we know is that it is hard. And that meanwhile, the Web still mostly works. I fail to see how abiding by a particular syntax for names (RFC 2396) exempts us from this the complexities that have always surrounded any attempts to reason precisely about naming and reference. It's just plain hard. The more we can persuade people to use URIs in the same way, the better our Web information systems will get. But please let's not over-sell the merits of URIs. All of which is a grumpy way of saying that there is no merit whatsoever in arguing about whether *all* objects are 'in principle' (which principle?) URI nameable, since we have (and I claim will *never* have) a clean account of naming. There are no facts of the matter about how many names an object has, whether those names are URIs or not. But the Web still works... Dan -- mailto:danbri@w3.org (W3C/ILRT) http://www.w3.org/People/DanBri/
Received on Thursday, 12 April 2001 21:50:41 UTC