Question 1-5

Suppose we have a parent predicate defined in Prolog.

parent(Cheri, Carl).
parent(Cheri, Hal).
parent(Chuck, Carl).
parent(Dorothy, Cheri).
parent(Dorothy, Vicki).

Define a Prolog predicate sibling(A,B) based on the parent predicate that represents whether A and B are siblings.

Solution

sibling(A, B) :- parent(X, A), parent(X, B).