- From: Sandro Hawke <sandro@w3.org>
- Date: Sun, 20 May 2001 08:25:09 -0400
- To: pat hayes <phayes@ai.uwf.edu>
- cc: www-rdf-logic@w3.org
pat: > sandro: > >What possible advantage does "urn:elvis" (or any other URI-like thing) > >have over "elvis" as a logic symbol? > > > >1. We can prevent unintentional re-use. This is like > > com.sun.SomeJavaClass or w3c_some_C_library_function. Doing this > > allows us to skip a symbol translation stage in reasoning about > > two different expressions. > > Several problems with this include the fact that often, with names, > one NEEDS to have 're-use' in order to refer to something. That is > largely what names are for in social use of language, if you think > about it. But I have argued this to death in earlier threads. Er yes -- that's why I said "prevent UNINTENTIONAL re-use." In logic terms, I believe this feature lets you make skolum functions/constants. > > I think there are cases, with agents communicating in a multi-path > > network, where the translation problem becomes impossible to solve > > without at least a mechanism for generating unique agent (or > > document) identifiers. And if you need that generation mechanism > > for agents, you might as well make it available for all objects. > > Not all names are identifiers! Most objects do not have identifiers > in this sense. > A name-clash of identifiers is a computational error. Re-use of names is not. Ah, sorry -- I remember you arguing about the distinction between names and identifiers earlier, but I have neither understood nor started using it. When I'm writing primarily to you, I try to use the term "symbol." > >2. There are some social mechanisms in place to designate who has > > authority to define the denotation of the symbol. The clearest is > > probably urn:oid, which involves a whole mechanism in > > international law deligating denotational authority. (I don't > > know how well it works, but I've heard it tries.) > > Denotational authority? Wow. You and I definitely live in different > universes. There are no laws about denotational authority. The only > person who has "denotational authority" (impossible to type this > without smiling) over the words I use is me. I'm not saying denotational authorities work well, just that some people try to create them. Certainly bodies of law do define certain terms. In Massachusetts, I beleive I can be thrown in jail for calling myself a "doctor" or "lawyer" (in certain situations), but I'm certainly free to call myself a "shmoctor" or "arguer". > > I have no idea how this actually helps, beyond the functionality > > in point #1. Who cares if symbols starting urn:oid:1.2.840.113556 > > may only legally be "defined" by Microsoft? How do we use that > > fact? > > > >3. Some URIs can point humans and/or machines to some definitional > > text, possibly even some permanent definitional text. But is > > there an advantage to > > "elvis according to the formal definition at http://example.com/elvi > s" > > (aka "http://example.com/elvis#elvis") > > over > > "elvis234234" [elvis with some uniqueness mechanism] > > with the nearby assertion > > ("elvis234234", formal_definition_website, "http://example.com/elvis > ") > > > > The later form gives us much more flexibilty to explore approaches > > to "definition", whatever that means. > > The denotation of my name is me, not a definitional text. Of course. But some people think the symbol one uses in public for a thing should be text which includes instructions for finding out more about the thing. Is that useful? -- sandro
Received on Sunday, 20 May 2001 08:25:13 UTC