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Getting Cyc-ed about Inference

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Title: Getting Cyc-ed about Inference


1
Getting Cyc-ed about Inference
  • Christopher Cox

2
What is Cyc?
  • The Worlds Leading Provider of Formalized
    Common Sense
  • (currently 200,000 terms each with several
    assertions over 1,000,000 rules )

3
What is Cyc?
  • Founded in 1984 by Stanford professor Doug Lenat,
    it was a project in the MCC (Microelectronics and
    Computer Technology Corporation) until 1994, when
    Lenat left to form Cycorp
  • Objective Codify the millions of pieces of
    knowledge that comprise common sense
  • When people die, they stop buying things
  • Kerosene flows downhill
  • When a bowl is overturned, its contents fall out.

4
Common Sense
  • Cycs stated goal
  • Break the software brittleness bottleneck
    once and for all by constructing a foundation of
    basic common-sense knowledge-a semantic
    substratum of terms, rules and relations, a deep
    layer of understanding that can be used by other
    programs to make them more flexible.
  • Basic Common-Sense Knowledge
  • "In modern America, this encompasses recent
    history and current affairs, everyday physics,
    household chemistry, famous books and movies and
    songs and ads, famous people, nutrition,
    addition, weather, etc

5
Overview
  • What is Cyc
  • OpenCyc, ResearchCyc, Full Cyc
  • Whats in Cyc?
  • The Big Picture
  • Microtheories
  • Predicates and Functions
  • Arguments and Types
  • Lexicon
  • How do I use it?
  • Cyc at Stanford
  • Cyc Browser
  • Java and Applications

Several examples and images come from the more
extensive, online OpenCyc Tutorial www.cyc.com/doc
/tut
6
Whats in Cyc?
  • A Knowledge Base (KB) consisting of terms
  • Dog, DogFood, Doghouse, SnoopDoggyDogg
  • Assertions that relate these terms.
  • Ground Assertions
  • (isa MyDogSharkey BelgianSheepdog)
  • (genls BelgianSheepdog Dog)
  • Rules, which derive assertions from Ground
    Assertions
  • (isa THING COL )
  • (genls COL SUPERCOL) ---gt
  • (isa THING SUPERCOL)

7
The Knowledge Base
Upper Ontology Abstract Concepts
EVENT ? TEMPORAL-THING ? INDIVIDUAL ? THING
Core Theories Space, Time, Causality,
Knowledge Base Layers
For all events a and b, a causes b implies a
precedes b
Domain-Specific Theories
For any mammal m and any anthrax bacteria a, ms
being exposed to a causes m to be infected by a.

Facts Instances
John is a person infected by anthrax.
8
A Dog is a ..
  • Agent Agent-Generic AirBreathingVertabrate
    Animal Agent Agent-Generic AirBreathingVertabrate
    Animal AnimalBLOBilateralObject
    BiologicalLivingObect CanineAnimal
    CarnivoreCarnivoreOrder ChordataPhylum Coelmates
    Container-Underspecified Dog EukaryoticOrganism
    Eutheria FrontAndBackSidedObject Heterotroph
    HexelateralObjectHomeotherm HumanScaleObject
    Individual IndividualAgentLeftAndRightSidedObject
    Location-Underspecified MammalNaturalTangibleStuff
    NonPersonAnimal OrganicStuff Organism-Whole
    PartiallyTangible PerceptualAgent
    Region-UnderspecifiedSentientAnimal
    SolidTangibleThing SomethingExistingSpatialThing
    SpatialThing-Localized System-GenericTemporalThing
    TerrestrialOrganism ThingTopAndBottomSidedObject
    Trajector-Underspecified VertebrateAnimalBLOBila
    teralObject BiologicalLivingObect CanineAnimal
    CarnivoreCarnivoreOrder ChordataPhylum Coelmates
    Container-Underspecified Dog EukaryoticOrganism
    EutheriaFrontAndBackSidedObject Heterotroph
    HexelateralObjectHomeotherm HumanScaleObject
    Individual IndividualAgentLeftAndRightSidedObject
    Location-Underspecified MammalNaturalTangibleStuff
    NonPersonAnimal OrganicStuff Organism-Whole
    PartiallyTangible PerceptualAgent
    Region-UnderspecifiedSentientAnimal
    SolidTangibleThing SomethingExistingSpatialThing
    SpatialThing-Localized System-GenericTemporalThing
    TerrestrialOrganism ThingTopAndBottomSidedObject
    Trajector-Underspecified Vertebrate

9
Microtheories
  • A way of grouping assertions and rules which
    share a set of assumptions about a domain, level
    of detail, period in time, source, topic, etc.
  • Each KB assertion occurs within some microtheory
  • These allow for a KB that copes with global
    inconsistency and that can focus inference
    according to necessary detail

10
Microtheories
  • Though no monotonic contradictions are allowed
    inside a microtheory, assertions in different
    microtheries may be inconsistent
  • Time
  • MT1 Mandela is an elder statesman
  • MT2 Mandela is the President of South Africa
  • MT3 Mandela is a political prisoner
  • Granularity/domain
  • MT1 Tables are solid
  • MT2 Tables are mostly space
  • Microtheories are arranged in an inheritance
    heirarchy

11
Microtheory Inheritance genlMt
BaseKB
genlMt
genlMt
NaiveSpatialMt
MovementMt
genlMt
genlMt
genlMt
NaivePhysicsMt
NaturalGeographyMt
genlMt
TransportationMt
12
Predicates and Denotational Functions
  • Predicates are truth-functional relations which
    can be evaluated according to facts in the KB and
    used to make sentences that are true or false
  • Usually Lowercase
  • (objectHasColor BrownDog Brown)
  • (memberStatusOfOrganization Norway NATO
    FoundingMember)
  • Functions take arguments to denote Non-Atomic
    Terms (NATs), expressions that represent things
  • Usually Uppercase
  • (FruitFn AppleTree) denotes an apple
  • (BorderBetweenFn Sweden Norway) denotes the
    border between Sweden and Norway.

13
Arity and Argument Types
  • Every predicate or function is defined with
    particular arity and argument types
  • Arity Number of Arguments
  • (arity mother 2) (arity MotherFn 1)
  • Argument Types use isa and genl relations
  • (arg1Isa mother Animal)
  • (arg2Isa mother FemaleAnimal)
  • (arg1Isa TransportViaFn ExistingObjectType)
  • (arg1Genl treatmentTypeAppliedToConditionType
  • MedicalTreatmentEvent)

14
Predicates and Rules
  • Can be built to form meaningful, well-formed
    logical sentences
  • You can add your own, using ASSERT

Mt AgentGMt Rule (implies (and
(isa ?HELP HelpingAnAgent)
(performedBy ?HELP ?HELPER)
(beneficiary ?HELP ?HELPED)
(positiveVestedInterest ?HELPER ?HELPED)
15
Specialized Content
  • Cyc has several specialized and useful areas of
    KB content
  • Times and Dates temporallyIntersects,startsAfterSt
    artingOf,YearsDuration
  • Spacial Properties and Relations
  • constituent, ingredient, 60 in predicates,
  • 60 Shape Attributes
  • Event Types, with Roles and Actors
  • MovementEvent, MedicalTreatmentEvent,
    GivingSomething

16
The Cyc Lexicon
  • Cyc also knows a lot about English
  • There are entries for Lexical items as well
  • Treat-TheWord Use-TheWord
  • Several predicates express relationships which
    translate English expressions into CycL (and vice
    versa)

(verbSemTrans Use-TheWord 0 TransitiveNPFrame
(and (isa ACTION UsingAnObject)
(performedBy ACTION SUBJECT)
(instrument-Generic ACTION OBJECT)))
17
Important Lexical Predicates
  • denotation -- Relates a LexicalWord and
    SpeechPart to some denotedThing (e.g. some
    Individual or Collection).
  • multiWordString -- Relates a list of strings
    (e.g. ("hot")), a LexicalWord (e.g. Dog-TheWord),
    and a SpeechPart to some denoted Thing (e.g.
    HotDog) c.f. MultiWord -PhrasePrediciate.
  • verbSemTrans -- Relates a LexicalWord, sense
    number, and SubcategorizationFrame to a
    NLTemplateExpression c.f. SemTransPredicate.
  • nameString -- Relates a Thing to a string which
    (conventionally) refers to it
  • Well do some examples

18
The Cyc Browser
  • To run the Cyc KB Browser
  • Run an image on a ja- machine.
  • Move to /scr/nlp/src/cyc/cyc1.0enterprise/
  • Run ./run-cyc.sh , a Cyc will start to run on
    your desktop.
  • You can use the SubL interactor directly at the
    prompt
  • Or you can load up a browser from the ja- machine
    (youll need to forward the desktop image to your
    machine) and set the address to
  • http//localhost3602/cgi-bin/cyccgi/cg?cb-start

19
Exploring Cyc
  • http//researchcyc.cyc.com/
  • Playing around with the Browser is only way to
    really learn whats in Cyc.
  • Logging In
  • The Search Box
  • The Heirarchy Browser
  • Documentation (usr/pass rcyc/rcyc)
  • Ask
  • Assert
  • Query
  • Toolbar
  • Dont use the parser

20
Example Application Cyc in RTE
  • Were looking at using Cyc the context of
    Recognizing Textual Entailment
  • Dependency parses are a good starting point for
    Cyc

(PID 702, Hypothesis) In the late 1980s Budapest
became the center of the reform movement.
21
RTE in a Nutshell
bought
object
subj
Synonym Match Cost 0.2
Chris (person)
car
Exact Match Cost 0.0
Hypernym Match Cost 0.4
purchased
object
subj
BMW
Chris (person)
Vertex Cost (0.0 0.2 0.4)/3 0.2 Relation
Cost 0 (Graphs Isomorphic) Match Cost
0.55 (0.2) (.45) 0.0 0.11
22
Cyc and Java
  • We clearly need a way to interact with the Cyc KB
    programatically
  • Cyc APIs exist for Java and Python
  • (check out /src/nlp/src/cyc/api/java/OpenCyc.jar)
  • Documentation is sparse
  • Cyc could be really valuable, if we can figure
    out a way to get around whats missing
  • Ive got code (soon to be in JavaNLP) for generic
    interactions with the CycKB, and for searching
    Cyc space along genls relationships as a measure
    of verb similarity
  • Its a huge KB, so use your imagination

23

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