Presentation Transcript

1. OpenCyc

   By Benjamin susman
2. Introductions Commonsense knowledge:
3. Outline Background information OpenCyc details Cyc Ontology CycL – Cyc’s language NLP in Cyc Setting up OpenCyc Demo
4. What is Cyc? Rich knowledge modeling language Large corpus of formally modeled knowledge with a wide breadth Efficient inference engine Written in LISP and CycL (Cyc language) Designed as a way to provide common sense or world knowledge and provide methods for reasoning around this knowledge ~ 900 person-years of effort Cycorpheadquartered in Austin, Texas; offices in Ljublijana, Slovenia
5. Timeline 1984: Cyc Project founded by Dr. Douglas Lenat as a lead project in the Microelectronics and Computer Technology Corporation (MCC). 1994: Cycorp was founded to further develop, commercialize, and apply the Cyc technology. 1996: Cycorp gets its first substantial government contract 2002: OpenCyc Version 1 Released: only included 6,000 concepts and 60,000 facts 2006: ResearchCyc Version 1 Released: adds additional knowledge base, English parsing and generation tools, and interface for knowledge editing and querying 2012: OpenCyc Version 4 Released: Includes ~239,000 terms; ~2,093,000 triples
6. OpenCyc details Available under Apache version 2 license (free software license) OpenCyc includes a subset of functionality from Cyc One way for accessing OpenCyc KB (knowledge base) is through OpenCyc KB Browser. OpenCyc criticized for restrictiveness: Missing instance-level knowledge Lacking any reasoning capability Being formally inconsistent The 3rd is most difficult to deal with since it has been hand-crafted Other problems addressed by ResearchCyc or EnterpriseCyc
7. CycL – The basics Language that makes up most of Cyc Some similarities to LISP #$Collection = Class, something that has instances #$Individual non-set/class (incl. relations, strings, numbers) #$isa = instance of #$genls = subclass of (“is-a”) Operators are built-in code-supported #$Predicates: #$and #$or #$not #$implies #$arity #$thereExists #$assertedSentence #$knownSentence #$arg1Isa #$interArg[Isa/Genl/Reln/Format]N-M #$resultIsa
8. CycL – The basics Definitional Assertion of isa: (isaisaBinaryPredicate) (arg1Isa isa Thing) (arg2Isa isa Collection) Example (isa Benjamin-Susman Individual)
9. CycL Visualized
10. Cyc Ontology Separated into 3 parts: upper, middle, and lower Upper level Contains the most broad abstract concepts, universal truths Smallest but most widely referenced area of Cyc ontology Middle level Not universal, but widely used abstraction layer Examples: geospatial relationships, broad knowledge of human interactions, or everyday items and events Lower level Domain specific knowledge Example: information about chemistry, biology, etc.
11. Cyc Ontology – Upper Level (comment Event “An important specialization of Situation, and thus also of IntangibleIndividual and TemporallyExistingThing. Each instance of Event is a dynamic situation in which the state of the world changes; each instance is something one would say ‘happens’. Events are intangible because they are changes per se, not tangible objects that effect and undergo changes. Notable specializations of Event include Event-Localized, PhysicalEvent, Action, and GeneralizedTransfer. Events should not be confused with TimeIntervals.”) (isa Event TemporalStuffType) (isa Event Collection) (quotedIsa Event PublicConstant-CommentOK) (quotedIsa Event VocabularyConstrainingAbstraction) (genls Event Situation) (disjointWith Event PositiveDimensionalThing)
12. Cyc Ontology – Upper Level (cont.) (genlsInstantaneousEvent Event) (genlsHelicopterLanding Event) inferred knowledge (genls (BecomingFn Intoxicated) Event) (relationExistsAll victim Event Victim-UnfortunatePerson) For every instance of the collection Victim-UnfortunatePerson, there exists an Event in which that person was the victim—i.e., an event for which these statements hold: (victim ?SOMEVICTIM ?SOMEEVENT) (isa ?SOMEVICTIM Victim-UnfortunatePerson) (isa ?SOMEVICTIM Event))
13. Cyc Ontology – Middle Level (comment SocialGathering “A specialization of SocialOccurrence. Each instance of SocialGatheringis an intentional social gathering of people who have the same or similar purposes in attending, and in which there is communication between the participants. Specializations include BabyShower, Carnival, and Rally. Note that a group of people waiting to board an elevator is not typically a SocialGathering, even though they share a common purpose, since they are not expected to talk to each other.”) (disjointWithSocialGatheringSingleDoerAction) (disjointWithSocialGatheringConflictEvent) (disjointWithSocialGatheringIntrinsicStateChangeEvent) (keStrongSuggestionPredsSocialGatheringdateOfEvent) Although it is not semantically required, it is likely that getting a dateOfEvent assertion for any given instance of SocialGatheringwould be appropriate or desirable. (requiredActorSlotsSocialGathering attendees) In every social occasion something must play the role of attendees.
14. Cyc Ontology – Lower Level (comment ChemicalReaction“A collection of events; a subcollectionof PhysicalTransformationEvent. Each instance of ChemicalReaction is an event in which two or more substances undergo a chemical change, i.e., some portions of the substances involved are transformed into different ChemicalSubstanceTypes. The transformations are brought about by purely chemical (including biochemical) means which affect chemical bonds between atoms in the molecules of stuff. Examples of ChemicalReaction: instances of CombustionProcess; instances of Photosynthesis-Generic.”) (keGenlsStrongSuggestionPreds-RelationAllExistsChemicalReactioncatalyst) (genlsChemicalReactionPhysicalTransformationEvent) (genlsCombustionReactionChemicalReaction) (genlsExothermicReactionChemicalReaction) (genlsChemicalBondingChemicalReaction)
15. Cyc Ontology – Lower Level (cont.) (arg1Genl availableReactantTypeInReactionTypeChemicalReaction) The first argument to an assertion made using the predicate availableReactantTypeInReactionTypemust generalize to some chemical reaction. (comment CombustionReaction“A specialization of both ChemicalReactionand CombustionProcess. Each instance of CombustionReaction is a rapid chemical reaction that produces a flame. Many combustion reactions involve oxygen from the air as a reactant.”) (genlsCombustionReactionCombustionProcess) (genlsCombustionReactionChemicalReaction) (outputsCreated-TypeTypeCombustionReaction Flame) Events which are CombustionReactions have members of the collection Flame as outputs.
16. CycL Example (isaBurningOfPapalBullSocialGathering) Because this is an instance of SocialGathering, it is an known to be an instance of Event and to have attendees. (eventOccursAtBurningOfPapalBullCityOfWittenburgGermany) (dateOfEventBurningOfPapalBull (DayFn 10 (MonthFn December (YearFn 1520)))) (attendee BurningOfPapalBullMartinLuther-ReligiousFigure) Martin Luther is already represented in the KB, along with basic biographical information such as birth and death date, country of residence, and native language. (relationInstanceExistsMinBurningOfPapalBull attendees UniversityStudent 40) At least forty university students attended the event. RelationInstanceExistsMin is a rule macro predicate.
17. CycL Example (cont.) (isaBurningOfPapalBull-Document CombustionProcess) (properSubEventBurningOfPapalBull-Document BurningOfPapalBull) (relationInstanceExistsinputsDestroyedBurningOfPapalBull-Document (CopyOfConceptualWorkFnPapalBull-ExcommunicationOfLutherCW) The thing destroyed is a member of the functionally defined collection “all copies of the conceptual work PapalBullExcommunicationOfLuther”. The distinction between the conceptual artifact and the specific copy being burned prevents Cyc from concluding that the conceptual work has been utterly destroyed (in the same way that burning a copy of Moby Dick does not destroy the work Moby Dick generally). (thereExists ?EVT (and(performedBy?EVT MartinLuther-ReligiousFigure) (causes ?EVT BurningOfPapalBull-Document))) The actual burning of a document was caused by some additional sub-event EVT (such as holding a match to it or throwing it into a fire). Unlike the distinction between the social gathering and the actual burning of the document, both of which are reified events, this event is defined implicitly, because there is nothing else to say about it.
18. NLP in Cyc – The lexicon Backbone of NL system Links between English words and Cyc constants are stored Every word contained as a Cyc constant Constant designated with “#$”
19. NLP in Cyc – Syntactic Parser Makes multiple parse trees for ambiguous (outputs all parse trees allowed by rules) Parse tree 1 Parse tree 2 {:SENTENCE {:NP {:DETP {#$Determiner [the]}} {:N-BAR {#$SimpleNoun [man]}}} {:VP {#$Verb [saw]} {:NP {:DETP {#$Determiner [the]}} {:N-BAR {:N-BAR {#$SimpleNoun [light]}} {:PP {#$Preposition [with]} {:NP {:DETP {#$Determiner [the]}} {:N-BAR {#$SimpleNoun [telescope]}}}}}}}} {:SENTENCE {:NP {:DETP {#$Determiner [the]}} {:N-BAR {#$SimpleNoun [man]}}} {:VP {#$Verb [saw]} {:NP {:DETP {#$Determiner [the]}} {:N-BAR {#$SimpleNoun [light]}} {:PP {#$Preposition [with]} {:NP {:DETP {#$Determiner [the]}} {:N-BAR {#$SimpleNoun [telescope]}}}}}}}}
20. NLP in Cyc – Semantic Interpreter Cyc-NL's semantic component transforms syntactic parses into CycL formulas Semantic structures are built up piece-by-piece and combined into larger structures. For each syntactic rule, there is a corresponding semantic procedure which applies. Verb driven: Example: "Mary believes that the blue hat is pretty" (#$believes :SUBJECT :CLAUSE).
21. NLP in Cyc – NL Generation Cyc's natural language generation capabilities include (according to Cyc): Multi-lingual support Alternative paraphrasing based on desired verbosity, register, etc. Selective inclusion/exclusion of text based on expectations of the user's information needs Extensible lexifications for individual concepts Extensible generation templates for predicates and sentences Can create output without requiring user to understand CycL
22. Setting up OpenCyc System requirements 3G RAM 64 bit system (No 32 bit support) 1G disk space Setup Download and unzip folder Available for Windows and Linux based systems Windows: opencyc-4.0\scripts\run-cyc.bat Linux: opencyc-4.0/scripts/run-cyc.sh
23. Setting up OpenCyc Access Use web browser: http://localhost:3602/cgi-bin/cyccgi/cg?cb-start Start as Guest account (documentation bad) Login as CycAdministrator (Note typo in the prompt when OpenCyc starts) Make new account, allow features should now be available
24. Demo Let’s run it!
25. Research CycAnyone? http://www.cyc.com/downloads/ResearchCyc_License_Rev2.1.pdf
26. References Primary source of info: http://www.cyc.com/platform/opencyc Cynthia Matuszek, John Cabral, Michael Witbrock, John DeOliveira. An Introduction to the Syntax and Content of Cyc: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.68.1357&rep=rep1&type=pdf CycL Visualization courtesy of: http://www.webstructor.net/worlds/cycl.html Used for timeline and finding release dates: http://en.wikipedia.org/wiki/Cyc Gave perspective on Cycorp’s funding, long term goals, and organizational setup: http://www.technologyreview.com/news/403803/cycorp-the-cost-of-common-sense/ Copy of ResearchCyc’s License agreement: http://www.cyc.com/downloads/ResearchCyc_License_Rev2.1.pdf NLP in Cyc: http://www.cyc.com/cyc/nl