Fit3080 Tutorial

Information Technology

FIT3080: Intelligent Systems
Ramesh Kumar Ayyasamy
Sunway Campus

ramesh [e-mail]

My tutorial ground rules
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During tutorial hours, you are allowed only to
- do the given tutorial tasks as mentioned in Moodle.

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During tutorial hours, you are not allowed to
- not allowed to use Facebook, YouTube or any such activities which is not related to tutorial.

- not allowed to use mobile phones or chatting with your girl friends or boy friends.
- not to make loud noise.

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Today’s Tasks – Tutorial 5
Knowledge representation
1. Exercise 6: First Order Logic
2. Exercise 7: Equivalence
3. Exercise 8: Unification
4. Exercise 9, 10: Resolution refutation

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Knowledge representation with Logic
Limitation on propositional logic
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Propositional logic can only handle TRUE, FALSE and has “No capability to handle
Uncertainty”, which is present in probability theory

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It conveys only TRUE or FALSE of the world, but “does not considers objects that has properties such as size, weight, color, nor their relationships between objects”

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No shortcuts or lacks expressiveness to describe the lots of activities happening around. •

First-order logic address the two limitations: objects and shortcuts
Refer, unit 7 in: https://www.ai-class.com/course/video/quizquestion/28

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Exercise 6: First-Order Logic

 First-Order Logic (FOL) is expressive to represent a good deal of our common sense knowledge.  Quantifiers used here are :  (For all),  x (there exists and x such that or For some x)

• Logical Operators used here are :

 , , , , 

 Example for First-order logic: “All kings are persons” can be written as
x King (x)  Person (x) .
“For all x, if x is a king, then x is a person.”, where x is a variable.
 Example for First-order logic: “ King John has a crown on his head” can be written as
 x Crown (x)  OnHead (x, John)
  appears to be the natural connective