CYC: The Common Sense Knowledge Base

1
CYC The Common Sense Knowledge Base

• By Jeremy Berman
• Alok Sahgal
• Dr. Reed CSC 550

2
Intro

• History
• What is Cyc?
• How does it work?
• Applications
• OpenCyc
• CycSecure

3
History of CYC

• Douglas B. Lenat and MCC (1984)
• GOFAI at a massive scale
• Construct Common Sense knowledge
• 3 million rules of thumb (2002)
• 300,000 terms

4
The First 10 Years

• Initial Goals (1984)
• representation language
• Interface for browsing and editing
• "cadre of lightly trained knowledge enterers"
  could easily use
• hooks to other AI programs.
• Midpoint Report (1990)
• CycL developed

5
Current State

• Now, anyone can be knowledge-enterer
• Web allows acceleration of knowledge entry
• Lenat claims human-level capacity in 5 years

6
How CYC Works

• Knowledge Server
• Knowledge Base
• Inference Engine
• CycL
• Cyc-NL
• Semantic
• Integration Bus

7
Knowledge Base

• Contains facts about everyday life (common sense)
• Terms written in CycL
• Assertions about terms
• Entered by humans
• Created by Cyc
• Microtheories

8
Inference Engine

• General logical deduction
• Best-first search
• Due to size, ordinary expert system methods of
  accessing data do not work.
• Cyc team developed new methods of retrieving data
  (secret)

9
CycL

• CycL
• Cyc representation language
• variation of first-order predicate calculus

10
CycL

• Constant - OrganicStuff 
• NAT - (FruitFn AppleTree)
• Variable -
• (colorOfObject Grass ?someColor)
• Expression
• (colorOfObject Grass Green)

11
CycL

• Assertions
• Animals sleep at home.
• (ForAll ?x (ForAll ?S (ForAll ?PLACE(implies
  (and(isa ?x Animal)(isa ?S SleepingEvent)(perfo
  rmer ?S ?x)(location ?S ?PLACE))(home ?x
  ?PLACE)))))
• if x is an animal and the performer of a sleeping
  event
• then the place where that event takes place is
  the home of x.

12
Cyc-NL

• Used to translate between English and CycL
• The man saw the light with the 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

13
Cyc-NL

• Fred saw the plane flying over Zurich.
• Fred saw the mountains flying over Zurich.
• Cyc knows that
• planes fly.
• people fly in planes.
• mountains do not fly.
• Zurich is a city.

14
Semantic Integration Bus

• Makes data from a variety of sources usable to
  the Inference Engine.

15
Applications

• OpenCyc
• Uses
• Goals of Project
• Demonstration
• CycSecure

16
OpenCyc Uses

• Allows user to create applications that access
  and use data in CycKB
• Starting point for
• Speech understanding
• Database integration
• Email prioritizing
• Game engines
• Letting people develop their own worlds

17
OpenCyc

• Goals of Project
• Growth of Knowledge Base
• Establish CycKB as the standard for
• knowledge representation/management
• database integration
• intelligent software applications

18
OpenCyc

• Goals cont.
• Raise awareness for symbolic knowledge
• Help to combine symbolic systems with emergent
  ones (neural nets, genetic algorithms, etc)

19
OpenCyc

• Demonstration
• http//www.opencyc.org/images/opencyc-kb-browser.g
  if

20
CycSecure

• Automated network auditing service that simulates
  network attacks
• First real commercial application
• Complements other network security apps

21
Anatomy Of CycSecure

• Network Configuration Simulator
• Inputs the data for security assessment
• CycSecure Knowledge Base
• Contains knowledge of vulnerabilities and
  patterns of attacks
• AttackPlan Analyzer
• Simulates a planned attack

22
How CycSecure Works

• Uses virtual network from NCS
• Finds vulnerabilities of network security
• DoDs Information Assurance Vulnerability
  Assessment

23
More about CycSecure

• Evolved Scanner
• Costs
• Still in beta-testing

24
Future of Cyc

• Online brokering of goods and services
• "Smart" interfaces
• Advancement gaming AI
• Improved speech recognition
• Sophisticated user modeling
• Local consistency

25
Conclusion

• KB is already enormous and broad
• Large corporate support
• Largest GOFAI attempt

26
References

• www.cyc.com
• www.opencyc.org
• Anthes, Gary H. Computerizing Common Sense,
  Computerworld
• April 8, 2002.