SUO: RE: Lifecycle Integration Schema
Dear Jon,
See comments below.
Matthew West
Principal Consultant
Shell Information Technology International Limited
Shell Centre, London SE1 7NA, United Kingdom
Tel: +44 20 7934 4490 Other Tel: +44 7796 336538
Email: matthew.west@shell.com
Internet: http://www.shell.com
> -----Original Message-----
> From: Jon Awbrey [mailto:jawbrey@att.net]
> Sent: 01 September 2003 18:47
> To: West, Matthew R SITI-ITPSIE; SUO
> Subject: Re: Lifecycle Integration Schema
>
>
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> LIS. Discussion Note 2
>
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> Matthew,
>
> New comments unindented below.
>
> Re: "thing"
>
> http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integrati
> on_schema/lexical/thing.html
>
> LIS: | A <thing> is anything that is or may be thought about
> or perceived,
> | including material and non-material objects, ideas,
> and actions.
>
> JA: A statement that begins "An X is any X that ..." is problematic.
>
> JA: I will pass it by for now, and treat it as a comment that tells me
> something about how you plan to use the word "thing", in
> some actual
> or potential relation to the things that you call
> "perceptions" and
> "thoughts", and applicable inclusively to all of the
> things that you
> call "actions", "ideas", "material objects", and
> "non-material objects".
>
> MW: It is normative text in the standard, but you are right
> not to worry too
> much about it. Thing is nearly equivalent to John Sowa's
> TOP, but within
> a 4D ontology, so a continuant is not an ISO15926 thing,
> since it doesn't
> fall within the paradigm. In a lattice of theories it
> would be the root
> for this 4D ontology, and fall somewhere under John Sowa's TOP.
>
> It's possible we use words like informative and normative differently.
MW: Yes. In ISO standards there are two types of text: Normative and
Informative. The normative text indicates what must be conformed to
by an implementation. The informative text is other material (here
NOTES and EXAMPLES) that provide additional information that may help
understanding, but do not have to be conformed to.
> Let's see if there's some way to cut to the chase and say what we are
> really doing when we spend time talking about words like "thing" and
> "things". The only reason for spending time on these sorts of words
> is that there is this sadder-but-hopefully-wiser history of crashing
> whole systems of thought when people tried to take on too much at
> these initial stages of the game.
>
> I understand you to be saying that you intend to apply the
> word "thing" to
> every object that arises in a particular discussion, and for
> my part I am
> content to work within one context of discussion at a time,
> so let us not
> spend too much time indulging in the speculation that we
> might just have
> some concept of anything whatever, independent of all
> practical contexts
> of discussion. If the instruction manuals for our logical formalisms
> do not come with formalizations of these "needless to say" sorts of
> understandings, then it is likely that we will need to write them,
> if not for our sake, then for the sake of computers yet unborn,
MW: Fine.
>
> Taken in a particular context of interpretation, then,
> there is a universe of discourse X, and there are terms,
> for example, the word "thing", that denote every element
> in X, or, said another way, whose denotation ranges over
> the whole universe of discourse X that is pertinent to
> a particular discussion.
>
> At this point, at least for my part, interest shifts to the
> many different
> universes of discourse that one may consider, the sorts of
> structures that
> they may have and the sorts of relationships that may exist
> among them.
> That is more or less why category theory got invented, to help us keep
> track of the ranges of variable words like "thing", which ranges of
> variation we now call objects in a category.
>
> MW: For the purpose of the SUO we would need to
> reword this definition at some point.
>
> Yes, but ...
>
> I still cannot see it as a definition,
> but it's okay to begin with undefined
> primitives, and statements of their
> relations to other terms, defined
> or otherwise.
MW: Fine. That is part of what needs to be fixed, but I still expect
the result to be a primitive. Most of our entity types probably are.
>
> LIS: | Every <thing> is either
> | a <possible_individual>,
> | or an <abstract_object>.
>
> JA: This is an informative statement.
>
> MW: But normative in standards terms.
>
> By "informative", I just mean that it conveys information.
> That is, the statement expresses a constraint among the
> things to which it and its component terms apply.
MW: OK Culture clash, but I understand you.
>
> JA: It specifies a mutual constraint on the applications of
> the three terms,
> "thing", "abstract_object", and "possible_individual".
> Moreover, it's
> a constraint that can be captured in zeroth order terms
> (boolean algebra,
> monadic predicates, propositional calculus, sentential
> logic, etc,) and
> expressed very succinctly in my favorite language for
> same, so I will
> capture it immediately in the following form:
>
> JA: ( thing ,( abstract_object ),( possible_individual ))
>
> JA: Roughly speaking, taken as an assertion, this says that
> every thing
> is either an abstract_object or a possible_individual,
> but not both.
>
> MW: Correct. If had had gone a couple of lines down
> you would have found the following EXPRESS:
>
> MW: ENTITY thing
> ABSTRACT SUPERTYPE OF (ONEOF(possible_individual,
> abstract_object));
>
> MW: ABSTRACT means it is only instantiated through its subtypes, and
> ONEOF means one or the other but not both. ABSTRACT is indicated
> in the diagram by the (ABS) in the entity type name, and the ONEOF
> is indicated by the "1" by the subtype/supertype tree.
>
> MW: We often did not bother to give these statements informally
> if the information was contained in the formal EXPRESS.
>
> Good, there are many interesting things here,
> that I hope to get back to at another time.
>
> LIS: | NOTE 1. Every <thing> is identifiable within a system.
> | System identifiers created by other systems and received
> | as part of a data exchange may be stored for future reference
> | as an identification, referring to the originating organisation
> | or system.
>
> JA: You are saying that you are really only thinking about things
> that have identifiers in given system, or names in a certain
> context of discussion. This is very significant and needs to
> be elevated to the level of an explicit principle, instead of
> being left implicit in a note that is likely to be neglected,
> in other words, relegated to a hidden axiom or constraint
> whose consequences are not critically reflected on.
>
> MW: Firstly NOTEs and EXAMPLEs are informative in standards terms.
>
> I probably need a definition of what you mean by "informative".
> It sounds like you are saying "not definitive" or "optional".
> The way I see it, if it's not avoidable, it's not optional.
MW: See above.
>
> However we gloss it, I am trying to indicate a potential risk of
> misinterpretation, of being taken to mean something that is very
> different from what one really intends, and there is a potential
> danger of, well, glossing over this point if we don't keep all
> the constraints and intentions in plain view. There is also
> an efficiency loss that comes from trying to do more than
> one really needs.
>
> MW: A data model is to support the holding of data about things.
> Here we are noting that different systems that might wish to
> communicate about some thing may have their own identifier
> for it, and that this is not a problem.
>
> LIS: | NOTE 2. Every example provided for other entity data types
> | declared in this schema is also an example of <thing>.
>
> JA: Okay for now, as long as it's just a comment.
>
> MW: It is, see above.
>
> This is beginning to worry me more.
> We may need a way of formalizing
> how seriously comments need to
> be taken.
MW: There is one. A standard declares whether each clause and annex
is normative or informative. Within normative annexes, informative
material is given in NOTES or EXAMPLES. This material is taken from
a normative clause in the standard.
>
> JA: There are some generic issues already arising here,
> that come up in every discussion of this type, but
> I'll need to think about some new ways to say them.
>
> Jon Awbrey
>
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