PROLOG
% The suicide example /* Domain theory */ kill(A,B) :- hate(A,B), possess(A,C), weapon(C). hate(W,W) :- depressed(W). possess(U,V) :- buy(U,V). weapon(Z) :- gun(Z). /* Training example */ depressed(john). buy(john, colt). gun(colt). /* operationality criteria */ operational(depressed(X)). operational(buy(X, Y)). operational(gun(X)).