let Y be non empty set ; :: thesis: for a being Element of Funcs Y,BOOLEAN
for G being Subset of (PARTITIONS Y)
for A, B being a_partition of Y st G is independent holds
Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G
let a be Element of Funcs Y,BOOLEAN ; :: thesis: for G being Subset of (PARTITIONS Y)
for A, B being a_partition of Y st G is independent holds
Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G
let G be Subset of (PARTITIONS Y); :: thesis: for A, B being a_partition of Y st G is independent holds
Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G
let A, B be a_partition of Y; :: thesis: ( G is independent implies Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G )
assume A1: G is independent ; :: thesis: Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G
'not' (All (All a,A,G),B,G) = Ex (Ex ('not' a),A,G),B,G by BVFUNC11:23;
hence Ex (Ex ('not' a),A,G),B,G '<' Ex ('not' (All a,B,G)),A,G by A1, BVFUNC11:17; :: thesis: verum