% Mizar problem: t8_boole,boole,124,67 fof(t8_boole,conjecture,( ! [A,B] : ~ ( v1_xboole_0(A) & A != B & v1_xboole_0(B) ) ), inference(mizar_bg_added,[status(thm)],[d5_xboole_0,dt_k1_xboole_0,fc1_xboole_0,rc1_xboole_0,rc2_xboole_0]), [file(boole,t8_boole)]). fof(d5_xboole_0,axiom,( ! [A] : ( v1_xboole_0(A) <=> A = k1_xboole_0 ) ), file(xboole_0,d5_xboole_0), []). fof(dt_k1_xboole_0,axiom,( $true ), file(xboole_0,k1_xboole_0), []). fof(fc1_xboole_0,axiom,( v1_xboole_0(k1_xboole_0) ), file(xboole_0,fc1_xboole_0), []). fof(rc1_xboole_0,axiom,( ? [A] : v1_xboole_0(A) ), file(xboole_0,rc1_xboole_0), []). fof(rc2_xboole_0,axiom,( ? [A] : ~ v1_xboole_0(A) ), file(xboole_0,rc2_xboole_0), []).