Trying to implement commutativity in Prolog

Question

I am trying to create a knowledge base. My problem has terminal/1 and connected/2 and I have defined the following rule:

connected(X,Y)         


        

Answer 1

I managed to figure this out.

I changed this:

connected(X, Y) :- is_connected(Y, X) /\ is_connected(X, Y).
is_connected(X, Y) :- terminal(X) /\ terminal(Y) /\ connected(X , Y).

to:

is_connected(X, Y) :- connected(Y, X); connected(X, Y).

As it turns out, I also need to be asking the corrected question. Instead of asking connected(X,Y), I will now be asking is_connected(X,Y).