Question

Write PROLOG program to solve this problem

Give a binary resolution proof that is found by PROLOG interpreter

I married a widow (lets call her W) who has a grown-up daughter (call her D). My father (F), who visited us quite often, fell in love with my step daughter and married her. Hence, my father became my son-in-law and my step-daughter became my mother. Some months later, my wife gave birth to a son (S1), who became the brother-in-law of my father, as well as my uncle. The wife of my father, that is, my step daughter, also had a son (S2)

Answer 1

PROLOG program:

male(i).
male(f).
male(s1).
male(s2).
married(i,w).
parent(w,d).
parent(f,i).
married(f,d).
parent(w,s1).
parent(i,s1).
parent(f,s2).
parent(d,s2).

married(X,Y) :- tmarried(X,Y).
tmarried(X, Y) :- married(Y,X).

female(X) :- not(male(X))

father(Parent, Child) :-
    parent(Parent, Child),
    male(Parent).

mother(Parent, Child) :-
    parent(Parent, Child),
    female(Parent).

sibling(X,Y) :-
    parent(F, X),
    parent(F, Y), X = Y.

sibling_in_law(X,Y) :-
    parent(P,X),
    parent_in_law(P,Y),
    X = Y.