re:SUO: RE: First piece of 4D ontology
### Ian, Matthew,
### am traveling in US so replies may be a bit slower. I had also noticed the relationship between in Matthew's axioms #3 and #4 but in fact, why does the comment of #3 talk about classes while the code is expressed using collection? Is that accidental or intentional. Similarly, is "member of" the same as "is a"?
### BTW these 4 axioms don't tell me a whole lot... not to mention the serious agreement one needs about the "exists" predicate and the implicit membership/is_a semantics. I wonder how to use them. Is there more to come?
--Robert Meersman
>
>Matthew,
>
> Please see my comments below.
>
>-Ian
>
>> -----Original Message-----
>> From: West, Matthew MR SSI-GREA-UK
>> [mailto:Matthew.R.West@is.shell.com]
>> Sent: Thursday, March 08, 2001 1:22 AM
>> To: Standard-Upper-Ontology (E-mail)
>> Subject: First piece of 4D ontology
>>
>>
>> Dear Colleagues,
>>
>> Please find below a first piece of a 4D ontology.
>>
>> I'd like to thank Pat Hayes for reviewing some early drafts.
>>
>> Comment text is of two types:
>> 1. Translations into English of the KIF below. I assume that
>> eventually automatic translation from KIF into e.g. ACE
>> will be possible for human interaction.
>> 2. Structuring information, e.g. Subject Area, Theory, Statement No.
>> These are things that I think we need to support engineering
>> an ontology (vs. saying what we mean) which I hope will be
>> supported by KIF before long.
>>
>> Comments are welcomed.
>>
>> ; Subject Area: Thing
>> ;
>> ; theory: individual and collection
>> ; uses:
>> ;
>> ; #1:
>> ;
>> ; For all X, X is a thing.
>> ;
>> ; i.e. that which everything is a member of.
>> ;
>> ; Note 1: In First Order Logic there is no need to make any
>> declaration,
>> ; (forall ?x ...) is sufficient.
>> ; Note 2: This means that all collections will be a subclass of thing.
>
>This axiom also appears in the merged ontology. There it has the following
>form: (forall (?X) (instance-of ?X Entity))
>
>> ;
>> ; #2:
>> ;
>> ; for all X, if there exists a Y and Y is a member of X, then X is a
>> ; member of collection.
>> ;
>> ; i.e. any thing that has a member is a collection.
>> ;
>> (forall ?x
>> (=> (exists ?y
>> (?x ?y)
>> )
>> (collection ?x)
>> )
>> )
>> ; Note: This (?x ?y) is not valid SUO-KIF today, but I understand it
>> ; will be in the near future.
>
>You could express (?x ?y) as (instance-of ?y ?x), which is syntactically
>well-formed SUO-KIF. However, it is also not a first-order sentence.
>
>I'm wondering what you mean by "collection" in your axiom. I thought we
>were using this term to denote things like wolf packs, football teams, etc.,
>which are set-like, in that they have members, but, unlike sets, they have a
>spatio-temporal location. However, if this is what you mean, then you
>exclude sets and classes, which have members but are not collections in the
>sense just explained.
>
>> ;
>> ; #3:
>> ;
>> ; For all X, X is an individual, or X is a class.
>> ;
>> ; i.e. everything is either an individual or a class
>> ;
>> (forall ?x
>> (or (individual ?x)
>> (collection ?x)
>> )
>> )
>
>Note that axiom #3 is redundant, since it is logically entailed by axiom #4.
>
>> ;
>> ; #4:
>> ;
>> ; For all X, if X is a member of collection then X is not a
>> ; member of individual and vice versa.
>> ;
>> ; i.e. any thing that is not a collection is an individual, and
>> ; vice-versa.
>> ;
>> (forall ?x
>> (<=> (collection ?x)
>> (not (individual ?x))
>> )
>> )
>
>My earlier comment about "collection" applies here as well, since this axiom
>appears to rule out sets and classes.
>
>> ;
>> ; end theory
>> ;
>> ; end subject area
>>
>> Regards
>> Matthew
>> ============================================================
>> Matthew West
>> Operations & Asset Management - Shell Services International
>> Shell Visiting Professor, The Keyworth Institute
>>
>> H3229, Shell Centre, London, SE1 7NA, UK.
>> Tel: +44 207 934 4490 Fax: 7929 Mobile: +44 7796 336538
>>
>> http://www.shellservices.com/
>> http://www.keyworth.leeds.ac.uk/
>> http://www.matthew-west.org.uk/
>> ============================================================
>>
>
>