Given the Prolog code motherlinajack fathertonyjack femaleju

Given the Prolog code:

mother(lina,jack).

father(tony,jack).

female(julia).

male(ken).

man(X):-father(X,_).

grandfather(X):-father(X,Y),father(Y,Z).

grandfather(X):-father(X,Y),mother(Y,Z).

Use only the above code to give one example of:

(a) an antecedent.

(b) a consequent.

(c) a fact.

(d) a rule.

(e) a variable.

(f) a constant.

(g) a conjunction (logical ‘and’) relation.

(h) a “don’t care” condition.

Now, based on the above program, give one example of:

(i) a query.

(j) a Prolog resolution.

(k) a Prolog instantiation.

Solution

Solution:-

(a) Antecedant-

In the given prolog Rule \"grandfather(X):-father(X,Y),father(Y,Z).\"

father(X,Y),father(Y,Z). is an antecedent.

An antecedent is true if Consequent is true.

(b) Consequent-

In the given prolog Rule \"grandfather(X):-father(X,Y),father(Y,Z).\"

grandfather(X) is consequent.

If Consequent is true then Antecent is true.

(c) Fact-

In the given prolog code \"female(julia)\". is a fact.

(d) Rule-

In the given prolog code \"grandfather(X):-father(X,Y),father(Y,Z).\" is rule.

(e) Variable-

In the given prolog code X,Y and Z are variables. In prolog Variable starts from capital letters.

(f) Constant-

In the given prolog code lina,jack,tony,julia and ken are constants as they are atomic values.

(g) Conjunction-

In the given prolog code \"grandfather(X):-father(X,Y),father(Y,Z).\"

father(X,Y),father(Y,Z) is a conjunction (logical ‘and’) relation. Conjuction is representeted in prolog as \',\'

(h) “Don’t care” condition-

In the given prolog code \"man(X):-father(X,_).\"

father(X,_) is a Don\'t care condition. Don\'t care condition represented as \'_\' in Prolog.

(i) Query-

\"?- mother(lina,X).\" is a query for the given prolog program and returnes X=jack.

(j) Prolog resolution-

\"grandfather(X):- man(X).\" is a resolution as it is derived from two rules and introduced a new rule.

(k) Prolog instantiation-

\"mother(lina,jack).\" and \"mother(Y,Z).\" it is derived that Y=lina. and Z=jack.

this is called instantiation. By instantiation we can derive the required variables values from tw same facts or rules.