set(auto). formula_list(usable). all x (man(x)->mortal(x)). % For all x, if x is a man then x is mortal man(socrates). % Socrates is a man -mortal(socrates). % Socrates is immortal end_of_list.
---------------- PROOF ---------------- 1 [] -man(x)|mortal(x). 2 [] -mortal(socrates). 3 [] man(socrates). 4 [hyper,3,1] mortal(socrates). 5 [binary,4.1,2.1] $F. ------------ end of proof -------------