W3C home > Mailing lists > Public > public-prov-wg@w3.org > September 2011

RE: Is _this_ what is meant by "Entity"?

From: Myers, Jim <MYERSJ4@rpi.edu>
Date: Sat, 3 Sep 2011 15:57:37 +0000
To: Simon Miles <simon.miles@kcl.ac.uk>, Provenance Working Group WG <public-prov-wg@w3.org>
Message-ID: <3131E7DF4CD2D94287870F5A931EFC23017C58@EX14MB2.win.rpi.edu>
 - I'm see no difference between what you and Graham expressed, but I
guess you want to ensure he didn't mean:
  a. "e0 is a file THAT HAPPENS AT THE MOMENT TO be at file system
location is /shared/crime.txt and which have been created by Alice"
  b. "e0 is COMPLETELY DEFINED BY BEING (not just a perspective on) a
file at /shared/crime.txt created by Alice"

--- ~Yes. Thinking of e0 as the file with some annotations on it doesn't seem deep enough to me - e0 is what a file would be in a theory where file objects can't move. Because e0 defines its behavior relative to certain processes of interest, it is different than a thing for which behavior hasn't been specified- it has a time/process dimension that a thing doesn't necessarily have (some things - like a resource identified by a persistent/cool URL already embed some notion of time and allowed processes (and they are entities/it is valid to assert that they are entities)- which is where some of the confusion between entity and thing might arise.) (Conversely, some entities - me defined to be the set of atoms in my body - have a rather strange evolution (I spread out over the planet over time...) and while I think I could define a web resource to represent that theory of me, I doubt one would ever find such a thing in the wild...)

 - Your example of overwriting a file in a single location nicely
illustrates nuances of the entity definition, and I guess we need
something of this sort in the primer. Though we might have to explain
things simply but not completely correctly before getting to accurate
but challenging :-)

 - I find your definition of entity more opaque than the current one
(sorry). What is an "asserted interpretation"?

--- Ah well... Somehow I'm trying to get the sense in my comment above - entity forces you to define a theory for how a thing behaves relative to processes of interest. You have to nail down how your notion of identity for whatever you're talking about is affected by relevant processes (When I talk about files, I consider two files to be different if their content is different, therefore content is a fixed attribute in my theory of the world and I can unabigously tell you about a given files provenance in terms of any editing processes that created it).

That may not help either...

Received on Saturday, 3 September 2011 15:58:17 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 13:06:41 GMT