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Unary Properties & Predicates

   
    ^universal
 [onto] class 
extension/scope
sub-section of the top-level ontology from [OntPrinc]  
 
[unary] PROPERTY aka. QUALITY
("property" [OntPrinc], "intrinsic property" [MB3], "quality"/"quality universal" [^])
  • A property is rigid if it is essential to all its instances, ie., cannot be removed from / lost by either of them [OntTax].
Between properties of certain kinds no subsumption (is-a) relationship can exist. Observing this in the development of a taxonomy can keep it more orderly (cf. the example in [OntTax]):
  • an anti-rigid property can't subsume rigid properies
  • an anti-external-dependency property can't subsume external-dependency properies (eg. PARENT depends externally on CHILD)
  • an anti-unity property can't subsume properies with unity conditions (eg. topological unity: the parts of an apple; morphological unity: the stars in a constellation; or functional unity: the parts of a bikini)
  • an IC-carrying property can't subsume non-IC-carrying properies
  • a unity-condition carrying property can't subsume non-unity-condition carrying properies
 
 
[+rigid]
[-IC]
 
[+rigid]
[+IC]
 
[-rigid]
[-indep.]
 
[-rigid]
[+indep.]
[-IC]
 
CATEGORY
±independent
Instances:
location[+indep.],
object[+indep.],
event[-indep.],
...
[general] TYPE  
IC
±independent
Instances: person[+indep.]
[general] ROLE
±IC
Instances: person[+indep.]
ATTRIBUTION
Instances: red, decomposable
- NB: color is not an attribution!
 
[original] type = IC-supplying  
*IC
supplies ("new") identity criteria (IC)

IOW, type = IC-supplying property:
A property "supplies" an IC if it is rigid, and there's a necessary or sufficient IC for it, and if the same IC is not already carried by all the properties (types) subsuming that property (it is a "new" IC) [OntTax].

 
quasi-type  
IC
merely carries the IC inherited from a subsuming type [OntTax]
 
[+IC]
material role  
IC
IC inherited from a [rigidly?] subsuming type (=> rigid IC)
Instances: student
 
[-IC]
formal role
no identity criteria
Instances: patient, part
with inherited IC  
IC
carries IC inherited from a subsuming type   ±rigid
... and what about IC-supplying roles ???
- cannot be bec. non-rigid IC makes no sense ?
Sortal [property] = IC-carrying  
IC
A property carrying an IC is called a sortal.
A property "carries" an IC if it is, or is subsumed by, a property supplying that IC [OntTax].

In particular, emerging properies [^] at higher system composition levels may be sortals by giving raise to new identity criteria.

  • Lowe's (1989) principle for well-founded ontologies/taxonomies: «No individual can instantiate both of two sorts [Strawson 1959] if they have different criteria of identity associated with them» [OntPrinc]
  • Sorts and their ICs are the basis for developing -> referential concepts
  • The definition of ontological levels (strata) can be based on what kind of identity criteria separates the concrete particulars at the respective level -> strata.

    Identity Criteria/Condition (IC)
    - «a principle for distinguishing and counting individual particulars» [Strawson 1959].
    - «criteria by which we are able to distinguish and count objects of the sort in question» [KRCR].

  • predicate
     [math] class 
    extension/scope
    Q: is there a [substantial] property for every predicate (in particular, for negations and disjunctions)? [yes]=> ^idealism
    [no]=> ^Bunge
    Unary Predicate
    Some relevant properties of unary predicates [FO 635]:
    • «[A] predicate is countable if, whenever it holds for an object x, it does not hold for a connected part of x. ... [A] predicate like PieceOfWood ... can be considered as countable if we assume that only a detached part of a piece of wood is itself a piece of wood»
    • «A predicate is temporally stable if, whenever it holds for an object at a time, then it must hold for the same object at another time. According to Givón (1979), noun-predicates like Student are temporally stable, while verbal forms like Studies are not». - My understanding: While a person P is studying (studies(P,t)), it is a student object S (student(S,t)). S is always a student object (student(S,t')), even when P stops studying (not studies(P,t')), only that then P is not S any more / S ceases to exist.
    • «[A] predicate is ontologically rigid if, whenever it holds for an object, it must hold for that object in any possible world. In other words, if an object has a rigid property, it cannot lose this property without losing its identity: an apple cannot cease to be an apple will still remaining the same object, while a student can easily have a temporary existence as a student»

     
    [+count]
    [+stable]
    Sortal [predicate] = IC-supply or carry?  
    IC/*IC(?)
    Strawson's (1959) sortal predicates are a concretization of unary logical/ structural/ taxonomic predicates: «According to Strawson, a sortal predicate (like Apple) "supplies a principle for distinguishing and counting individual particulars which it collects" whereas ...
    «A predicate will be a sortal predicate if it is both countable and temporally stable; in our proposal, unary structuring predicates (i.e. concepts) must all be sortals» [FO 635].
    [+rigid]
    Substantial Sortal
    =^= type (KR)
     
    IC
    «Within sortal predicates, a further distinction is made between substantial sortals like Apple and ...
    «Substantial sortals are ontologically rigid, and they correspond to what in KR terms may be called types; ...
    Instances: "apple", "color"
    [-rigid]
    Non-substantial Sortal
    =^= role-type (KR)
    =? material role
     
    IC
    ... and non-substantial sortals like Student, formally capturing some ideas proposed in Wiggins (1980)» [FO 635].
    ... non-substantial sortals are non-rigid, and they correspond to what have been called role-types (Sowa, 1988)» [FO 636].
    Instances: "student"
    ... cf. student is a material role = IC is inherited!
    discriminating but non-sortal
    ... whereas a non-sortal predicate like Red "supplies such a principle only for particulars already distinguished, or distinguishable, in accordance with some antecedent principle or method."» [FO 635].
    pseudo-sortal  
    IC(?)
    = "already distinguished" ? = with inherited IC ?
    Instances: "physical object", "gold"
    characterizing pred.
    =? attribution
    = not "already distinguished" ? = without IC ?
    Instances: "red", "studies"
    non-
    discriminating
    Instances: "entity"
     
     
    Location: http://www.cs.mun.ca/~ulf/two/on-unary.html (previously in gloss/cats.html) © Ulf Schünemann; ulf@cs.mun.ca; 120502, 100705