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*To*: <mark>*Subject*: version compare and partial orgls*From*: Eric Dean Tribble <tribble>*Date*: Sat, 2 Sep 89 20:01:52 PDT*Cc*: <us>*In-reply-to*: <MarkS.Miller'smessageofFri>,20 PDT <8909020409.AA12955@xxxxxxxxxx>

I'm going to respond to this stuff piecemeal. There is no *one true identity*. There is the canonical identity, which is a somewhat weaker notion. It provides the same power, however, and correctly maps to the semantics of sharing-inform and the idea of "best knowledge." Quite correct, there is no one true identity. However, as being sharing-informed is a monotonic process, one is getting better and better notions of identity. Therefore it is an interesting (but perhaps confusing) rhetorical device to speak of the true identity as the goal which the successive EAddresses of a DataObject approach but never reach. Alternatively, one can think of the true identity as the last canonical EAddress a given DataObject will ever have (at the end of time or some such). Given this, one can define freezing a DataStamp wrt sharing-inform: It is when you make an irrevocable commitment never to further sharing-inform the DataStamp (to do this, you mush have grabbed it). Once this is done, you know that the current canonical identity is the true identity. Canonical identity is MUCH weaker than true identity: Canonical identity is defined wrt currently & locally available knowledge. True identity is defined wrt knowledge which is omniscient across all time and space. (The kind of knowledge that the basic agent of standard economic theory is assumed to have. Where can we hire one?) I strongly dislike linguistic abstractions that can't be represented or achieved. Especially now that we agree that freezing doesn't affect sharing-informability, the notion of *true* identity is at best distracting. We can't represent it, it adds no useful insights as an analogy, and I think it is sufficiently opposed to what is really possible in a distributed system that it prevents us from considering the issues of DataObject identity correctly in the distributed context. I suppose the case isn't quite as strong as I'm making it, but.... dean

**Follow-Ups**:**version compare and partial orgls***From:*Mark S . Miller

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