Re: SUO: Re: nature of organisation
Pat,
I wanted to express my appreciation for the concrete content you've
provided here especially in your making a detailed proposal with axioms in
section (4). Ian and I have discussed this a bit more and we'll be making
a proposal for how to address these issues shortly that hopefully takes
into account the points you've raised.
Adam
At 04:02 AM 8/25/2001 -0400, Patrick Cassidy wrote:
>Adam --
> Four related points here in response to your note:
> (1) Can an organization have no members?
> (2) CYC #$Group vs. SUMO &%Collection,
> (3) Set vs. Class -- what is a Class?
> (4) Axioms relating to Organization
>
>(1) You believe that an organization cannot exist without members:
> > Another issue which is on my mind because of discussions with Chris
> > Welty is the essential property of an Organization. An Organization is not
> > an Organziation without people but may still be one without anything other
> > than it's members.
> As I understand corporation law, a legal corporation is a Legal
>Person
>that does indeed exist as an entity on its own, related to its members,
>but not depending on them for its existence (I'm not well-versed in
>Law, someone who is should have the definitive opinion -- I
>thought that dissociating the identity of a Corporation from its
>members was one of the points of incorporation, which creates
>a new legal person). The point I made is that the last member
>of a corporation may die or leave, and the Organization as
>a legal Person can still have assets and debts -- it still exists.
>If that happens, a court may appoint an executor to liquidate
>the assets, pay the debts, dissolve the corporation, and figure
>out who gets any leftovers. This is probably a rare condition, but
>it illustrates that Corporations, at least, may exist without members.
>Probably most organizations we deal with do exist only while the
>members exists, but I can think of other scenarios when an
>organization may temporarily have no members.
> Not quite on point, but related, is an incident when one
>church group decided to merge with another, and arranged for
>all it members to resign and then join the other church and
>transfer their remaining property to the other church.
> However, some members decided not to resign, and
>after the majority did, the residuals claimed the assets as
>belonging to them as the remaining members of the
>original corporation -- and the court agreed. The
>mistake was not to transfer the assets *before* resigning.
>One can imagine a similar situation when they *did* all
>resign -- the original corporation would exist without
>any members, and it would be even more of a legal mess.
> Even without the law, it seems reasonable to distinguish
>an Organization as a group of people bound by some set of rules,
> in which case it is *more* than just a group of people. If there
>are no organizational rules (at least tacit or informal) ,
>I think it would then be just a group of
>people and not an Organization.
>
>==========================================
>(2)
> My interpretation of the meaning of the CYC #$Group is
>not based on the name, but on the documentation, to wit:
>--------------
>(from the Public CYC)
>;;; #$Group
>(#$isa #$Group #$ObjectType)
>(#$genls #$Group #$TemporalThing)
>(#$genls #$Group #$Individual)
>(#$genls #$Group #$Situation)
>(#$comment #$Group "A collection of objects. Each element of #$Group is
>a composite object, made up of individual members which may be either
>events or objects. A group is related to its members by the predicate
>#$groupMembers (q.v.). Note that elements of #$Group are NOT
>collections; consider: a group has temporal extent and may have spatial
>extent and location, while a collection is timeless and abstract.
>Nonetheless, it is possible to define a collection parallel to any
>group, so that the #$groupMembers of that group are also instances
>(#$isa's) of the correlated collection; e.g., each toe on my left foot
>is both an element of the collection of my left toes and a member of the
>group of toes on my left foot. But that group (of my left toes) is a
>spatiotemporal thing, while the correlated collection (of my left toes)
>is NOT. Another example: if I consider a certain flock of pigeons as
>having a location, a spatial extent, and a time of existence, then I am
>considering (the pigeon flock) a group and NOT a collection. As a
>default, a group whose #$groupMembers are elements of
>#$SomethingExisting is itself an element of #$SomethingExisting; and a
>group whose #$groupMembers are elements of #$Event is itself an element
>of #$Event. Finally, unlike a collection, a group cannot be empty; a
>group must have some #$groupMembers, or there is no group (at that point
>in time). Examples of #$Group: #$QueensGuard, #$ThreeWiseMen,
>#$SantasReindeer, #$InternationalCommunity.")
>--------------------
>
> Of course, without the axioms and examples of useage we can't
>know for sure the details of what a reasoning process may do
>with such a concept. I presume that the individuals writing that
>documentation and the subsumption of #$Organization under #$Group
>never considered the possibility of an #$Organization
>persisting without members.
> One of the objectives, I would hope, for the
>SUO effort is to look critically at what has been
>done before and try to avoid what appear to be
>mistakes. The CYC usage appears to me to be a mistake,
>and the present SUMO usage looks similar.
>
> In SUMO 1.17, the definition of &%Collection
>appears to have a similar intention to the CYC
>#$Group, though the documentation in SUMO isn't as
>detailed, and the axioms are insufficient to
>make a distinction. A &%Group is a subclass of
>&%Collection, so it should have similar properties.
>
>
>Sumo definitions:
>----------------
>Group:
>(subclass Group Collection)
>(subclass Group Agent)
>(documentation Group "A &%Collection of &%Animals or &%Humans, e.g. a
>flock of sheep, a herd of goats, or the local Boy Scout troop.")
>
>(=>
> (and
> (instance ?GROUP Group)
> (member ?MEMB ?GROUP))
> (instance ?MEMB Animal))
>
>(subclass GroupOfPeople Group)
>(documentation GroupOfPeople "A &%Group consisting exclusively of
>&%Humans.")
>
>(=>
> (and
> (instance ?GROUP GroupOfPeople)
> (member ?MEMB ?GROUP))
> (instance ?MEMB Human))
>
>----------------
>Collection:
>(subclass Collection Object)
>(documentation Collection "Collections have &%members like &%Classes,
>but,
>unlike &%Classes, they have a position in space-time and &%members can
>be
>added and subtracted without thereby changing the identity of the
>&%Collection. Some examples are toolkits, football teams, and flocks
>of sheep.")
>
>(=>
> (instance ?COLL Collection)
> (exists (?OBJ)
> (member ?OBJ ?COLL)))
>
>==================================
>-----------------------------
>(3) Question:
> Set vs. Class
>
> A related question I have asked and do not yet know the answer
>to is why a "Set" in SUMO is a subclass of "Class" when in most
>theories the opposite is true. The definitions below
>say that a Set, "unlike &%Classes generally", does not
>have "an associated condition" (i.e. the standard interpretation
>of Class), but if Classes all had "an associated condition", then
>with the subclass relation in SUMO this would
>appear to violate the principle of inheritance of attributes;
>whereas, if the subclass/set order were reversed, the comment
>would be correct, but then Class would no longer be a
>generalization of Set.
> This would not be a contradiction if in fact Classes
>generally were not *required* to have an associated
>memership condition, but this would then differ from the usual
>interpretation of "Class" as it is used in ontologies
>(e.g. in the Ontolingua Frame Ontology, a Class is a subclass of
>Set; a Class is distinguished from a unary predicate only by
>a second-order predicate.) I can understand why one might
>want to define a "generalization" of Set so that it is
>not extensional, but I could not find defining axioms for
>"Set" or "Class" (except the extensionality axiom for &%Set),
>and from the definitions below I am not sure whether these
>two concepts actually serve their intended pupose.
>
> In the documentation, a distinction is drawn between
>Class and Collection that a collection can change
>members without changing the identity of the collection
>(a typical criterion for *intensional* definiton):
>
>"Collections have &%members like &%Classes, but,
>unlike &%Classes, they have a position in space-time and &%members can
>be
>added and subtracted without thereby changing the identity of the
>&%Collection."
>
> . . . but the documentation for &%Class specifically says that
>Classes are *not* defined extensionally, which is
>also what is implied for &%Collection by the documentation for
>&%Collection. Can you clarify this?
>
> Question: Is it *required* that a Class have an
>assocated membership condition (predicate)? If not, is there
>any concept that serves as an intensionally defined Set,
>like the "Class" of the Ontolingua Frame Ontology?
>If a &%Collection retains its idenity in spite of membership
>changes, does this not mean it is *necessarily* defined
>intensionally (by a defining predicate)?
> I think it's a good idea that the highest levels of the
>ontology should have the clearest and least
>ambiguous definitions.
>
>--------------------
> >From SUMO 1.17
>(subclass Set Class)
>(documentation Set "A &%Class that satisfies extensionality as well as
>other conditions specified by some choice of set theory. Unlike
>&%Classes generally, &%Sets need not have an associated condition that
>determines their membership. Rather, they are thought of metaphorically
>as `built up' from some initial stock of objects by means of certain
>constructive operations (such as the pairing or power set operations).
>Note that extensionality alone is not sufficient for identifying
>&%Classes with &%Sets, since some &%Classes (e.g. &%Entity) cannot be
>assumed to be &%Sets without contradiction.")
>
>
>(subclass Class Abstract)
>(documentation Class "&%Class generalizes that &%Set. &%Classes, like
>&%Sets, are collections of things. Accordingly, the notion of
>membership
>is generalized as well - a member of a &%Class is an &%instance the
>&%Class. &%Classes can differ from &%Sets in two important respects.
>First, &%Classes that are not explicitly identified as &%Sets are not
>assumed
>to be extensional. That is, distinct &%Classes might well have exactly
>the
>same instances. Second, &%Classes typically have an associated
>`condition'
>that determines the instances of the &%Class. So, for example, the
>condition `human' determines the &%Class of &%Humans. Note that some
>&%Classes might satisfy their own condition (e.g., the &%Class of
>&%Abstract
>things is &%Abstract) and hence be instances of themselves.")
>
>========================================
>(4). Axiomatization of Organization:
> (using SUMO terminology:
> This isn't carefully checked -- it may have errors, but this is
>the
> general idea)
>
>Relevant Hierarchy fragment:
>------------------
>Agent
> Organization
>NormativeProposition
> Rule
>Set
> Membership
> RuleSet
> OrganizationRules
>Collection
> OrganizationMembers
>------------------------
>
> ((1)) (subclass Organization Agent)
> ((2)) (subclass Rule NormativeProposition)
> (I can't easily axiomatize this because our discussions of
>Rules and Authorities
> and consequences of infringement never reached a
>conclusion)
> ((3)) "RuleSet is a Class each instance of which is a non-empty Set,
> all of whose elements are Rules"
>
> (subclass RuleSet Set)
> (forall ?RS
> (=>
> (instance ?RS RuleSet)
> (and
> (exists ?y
> (and
> (element ?y ?RS)
> (instance ?y Rule))
> (forall ?z
> (=>
> (element ?z ?RS)
> (instance ?z Rule)))
> )))
>
> ((4)) " Organizational Rules are a RuleSet"
> (subclass OrganizationRules RuleSet)
>
> " OrganizationRules and the Membership are proper parts of an
>organization:"
>
> (subclass Membership Set)
> (properPart OrganizationRules Organization)
> (properPart Membership Organization)
>
> " All elements of Membership are Agents"
> (as does CYC, we leave open the possiblity that a "member" of an
>Organization
> may be another organization (e.g. as with the UN, or a
>Chamber of Commerce))
>
> (forall (?MBSHP)
> (=>
> (instance ?MBSHP Membership)
> (forall ?MEMBR
> (=>
> (element ?MEMBR ?MBSHP)
> (instance ?MEMBR Agent) ))
> ))
>
> To allow empty sets of organization members, it
>is possible to define a set all of whose members (if
>they exist) are also members of an associated
>"OrganizationMembers" (this is one way to allow
>null membership -- another way is to allow a Collection
>to have null membership)
>
> ((5))" The group of OrganizationMembers is a Collection (because it
>may include other groups, not only individual people)"
> (subclass OrganizationMembers Collection)
>
> ((6)) "The Membership of an organization is a
> (possibly empty) set, all elements of
> which are also members of some instance of
>OrganizationMembers; for
> every non-null Set in Membership there is an associated
>Collection in OrganizationMembers"
>
> (subclass Membership Set)
> (forall (?MEMB ?MSHP)
> (=>
> (and
> (instance ?MSHP Membership)
> (element ?MEMB ?MSHP))
> (exists (?OM ?ORG )
> (and
> (instance ?ORG Organization)
> (instance ?OM OrganizationMembers)
> (properPart ?MSHP ?ORG)
> (member ?MEMB ?OM)))
> ))
>
>
>------------------
>
> Pat Cassidy
>
>
>
>======================
>Adam Pease wrote:
> >
> > Pat,
> > We should be a little careful here because it sounds like you may be
> > reading a bit into the names of terms - especially for Cyc since the axioms
> > aren't public.
> > Another issue which is on my mind because of discussions with Chris
> > Welty is the essential property of an Organization. An Organization is not
> > an Organziation without people but may still be one without anything other
> > than it's members.
> > But, overall, I think you're bringing up excellent issues. Could you
> > recommend a change in the axioms to accommodate these issues?
> >
> > Adam
> >
> > At 02:40 PM 8/24/2001 -0400, Patrick Cassidy wrote:
> >
> > >Concerning organizations:
> > > In the SUMO and also in the CYC, Organization is a
> > >subclass of Group, which is some assemblage of
> > >entities -- distinguished from a Set, which is
> > >considered "timeless an abstract". This
> > >distinction can be useful, but since groups of
> > >physical objects can then be considered as physical
> > >objects, it seems inappropriate to classify an
> > >organization as a subclass of Group. The members
> > >of an Organization form part of the Organization,
> > >but not the whole part. The rules creating the
> > >organization and defining the relations of members
> > >to each other and to the group are an essential
> > >part of an organization -- that's why it is
> > >"organized". I would prefer to see an
> > >Organization defined as an agent that has
> > >a set of operating rules and a group of people
> > >as a *Part* of the organization. A lot
> > >of "organizations" have only one person as
> > >a member (e.g. sole proprietarship corporations
> > >with no employees other than the owner).
> > >Consider a legal organization -- it is possible
> > >for the sole member to die, but for the
> > >organization to continue as a legal entity,
> > >e.g. if it has property and debts
> > >(the heirs might have to clean up the mess).
> > >In CYC, a Group must have at least one member.
> > >This situation would create a contradiction,
> > >unless one were to specify that every owner is
> > >de facto a member, and even then there could be
> > >an ownerless corporation whose affairs are
> > >terminated by some appointeee of the courts.
> > > To clarify the distinction, we could consider
> > >a mob or a crowd as consisting solely of
> > >its members. A mob or a crowd, then, could be
> > >an Agent that *is* a subtype of Group. The useful
> > >(I think) distinction would be to consider an
> > >Organization as an Agent that has a Group as a part.
> > > The way to specify roles in an organization
> > >is a different issue.
> > >
> > > Pat Cassidy
> > >
> > >===========================================
> > >
> >
> > Adam Pease
> > Teknowledge
> > (650) 424-0500 x571
>
>--
>=============================================
>Patrick Cassidy
>
>MICRA, Inc. || (908) 561-3416
>735 Belvidere Ave. || (908) 668-5252 (if no answer)
>Plainfield, NJ 07062-2054 || (908) 668-5904 (fax)
>
>internet: cassidy@micra.com
>=============================================
Adam Pease
Teknowledge
(650) 424-0500 x571