UGC NET CSE | December 2012 | Part 3 | Question: 58

Question

Skolmization is the process of

• A. bringing all the quantifiers in the beginning of a formula in FDL
• B. removing all the universal quantifiers
• C. removing all the extential quantifiers
• D. all of the above

Answer 1

ans is C) skolemization is the process of Removing all the existential quantifiers 

It is one of the steps in conversion  of first order logic sentences into its eqvt  CNF(conjuctive normal form)

Answer 2

Conversion of sentences FOL to CNF requires skolemization.

“Skolemization” is a transformation on first-order logic formulae, which removes all existential quantifiers from a formula. 
 

Skolemization Idea: 
Remove existential quantifiers by introducing new function symbols.
 

Skolemization Algorithm: 
Remove existential quantifiers and For each existentially quantified variable introduce a n-place function where n is the number of previously appearing universal quantifiers(before the removed existential quantifier).
Special case when no previous universal quantifier: introduce constants.
 

Three Practice Questions in the following PDF:

https://www.cs.toronto.edu/~sheila/384/w11/Lectures/csc384w11-KR-tutorial.pdf 

Try the following question:

Answer:

For Q1, Answer is A.

For Q2, Answer is A.

Answer 3

In logic and mathematics, skolmization is the process of replacing all existential quantifiers with Skolem constants. In formal logic, existential quantifiers are symbols that indicate the existence of at least one instance of a variable. Skolem constants are specific values that are used to represent the instances of a variable in a formula, allowing the formula to be evaluated or proven. Skolmization is often used as a step in the process of proving theorems in logic and mathematics.