Question

Suppose that Prolog facts are used to define the pred- icates mother(M, Y) and father(F, X), which represent that M is the mother of Y and F is the father of X, re- spectively. Give a Prolog rule to define the predicate grandfather(X, Y), which represents that X is the grand- father of Y. [Hint: You can write a disjunction in Prolog either by using a semicolon to separate predicates or by putting these predicates on separate lines.]

Answer 1

Answer and Explanation:

The Prolog rule expresses that logical implication (:-) describes the relationship between facts.

Prolog expressions are containing truth-functional symbols, which have the same intervention as in predicate calculus.

For example:  

English Predicate calculus prolog

and ^ ,

or v ;

By using information, given in the question,

We can make prolog:

Grandfather(X, Y)  :-mother(M,Y), father(X,M); father (F, Y), father(X,F)

Prolog (:- ) means define,

Prolog (,) represents a conjunction

And

Prolog (;) represent a disjunction