General Knowledge Ontological background for everything

D Goforth - COSC 4117, fall Ontology of everyday knowledge Mental events need to include representations of KB’s of other agents to reason about their plans and actions  Wants (AgentSmith, Dead(Neo)) need to ‘contain’ inconsistent knowledge to avoid interaction  Believes(Gambler1, Faster(HorseA,HorseB))  Believes(Gambler2, ~Faster(HorseA,HorseB))

D Goforth - COSC 4117, fall Ontology of everyday knowledge Mental events PROBLEM:  Wants (AgentSmith, Dead(Neo)) Is Dead(Neo) a predicate or a term?

D Goforth - COSC 4117, fall Ontology of everyday knowledge Mental events KB assumed KB of AgentX as objects “Rich(Paul)” ~Rich(Paul) Believes(AgentX,“Rich(Paul)”) to reason about what AgentX believes, run AgentX’s ‘interpreter’ with postulated reasoning powers

D Goforth - COSC 4117, fall Ontology of everyday knowledge  Time non-monotonic change in KB Frame problem – inferring what changes and what does not Actions as objects Reasoning about events, intervals fluent calculus

D Goforth - COSC 4117, fall Ontology of everyday knowledge  Default reasoning (missing information) (more on defaults later)

D Goforth - COSC 4117, fall Models of general knowledge 1.SUMO (Suggested Upper Merged Ontology)  Alan Pease, IEEE standard  Minimal – basis for adding domains 2.Cyc (“Sike”)  Douglas Lenat, Cycorp  Huge KB of common knowledge

D Goforth - COSC 4117, fall SUMO (Suggested Upper Merged Ontology)  Written in FOL  Approx 1000 concepts in ontology  Useful for basis of ‘expert’ projects which do not need ‘common sense’ knowledge  Open source

SUMO Base ontology – top-level ontology Entity PhysicalAbstract Object SelfConnectedObjectRegion Process Quantity Attribute Relation Proposition SetOrClass Complete SUMO Ontology (PDF)

D Goforth - COSC 4117, fall SUMO Example sub-ontology Units of Measure PhysicalQuantity UnitOfMeasure SystemeInternationalUnitOfMeasure ConstantQuantity AngleMeasure PlaneAngleMeasure

D Goforth - COSC 4117, fall SUMO  Equivalent to 2 nd order power by treating functions, predicates, logical operators as objects, also (not real examples) F(x)  (apply F x)(function) P(x,y)  (holds P x y)(predicate) R(x)  (instance x R)( “ ) (  A B)  (infer AND A B)(logical)

D Goforth - COSC 4117, fall SUMO example of logical - inverse (instance inverse BinaryPredicate) (instance inverse IrreflexiveRelation) (instance inverse IntransitiveRelation) (instance inverse SymmetricRelation) (domain inverse 1 BinaryRelation) (domain inverse 2 BinaryRelation) (=> (inverse ?REL1 ?REL2) (forall (?INST1 ?INST2) ( (holds ?REL1 ?INST1 ?INST2) (holds ?REL2 ?INST2 ?INST1)))) EXAMPLE: (inverse greaterThan lessThan)

(subclass AnimacyAttribute BiologicalAttribute) (exhaustiveAttribute AnimacyAttribute Living Dead) (documentation AnimacyAttribute "&%Attributes that indicate whether an &%Organism is alive or not.") (instance Living AnimacyAttribute) (documentation Living "This &%Attribute applies to &%Organisms that are alive.") (=> (and (instance ?ORGANISM Organism) (agent ?PROCESS ?ORGANISM)) (holdsDuring (WhenFn ?PROCESS) (attribute ?ORGANISM Living))) (instance Dead AnimacyAttribute) (subAttribute Dead Unconscious) (contraryAttribute Dead Living) (documentation Dead "This &%Attribute applies to &%Organisms that are not alive.") (=> (instance ?ORG Organism) (exists (?ATTR) (and (instance ?ATTR AnimacyAttribute) (attribute ?ORG ?ATTR))))

D Goforth - COSC 4117, fall Cyc  enCYClopedia  Douglas Lenat  Cycorp  1984->  general knowledge and common-sense reasoning

D Goforth - COSC 4117, fall Cyc (from cyc.com)  Ontology – 100,000’s of terms  Millions of assertions “Water is wet” “Everyone has a mother” “When you let go of things they usually fall.”  Open version available – opencyc.com Description of ontology on cyc website