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 holds 'not' (Ex (Ex a,A,G),B,G) '<' 'not' (All (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 holds 'not' (Ex (Ex a,A,G),B,G) '<' 'not' (All (All a,B,G),A,G)

let G be Subset of (PARTITIONS Y); :: thesis: for A, B being a_partition of Y holds 'not' (Ex (Ex a,A,G),B,G) '<' 'not' (All (All a,B,G),A,G)
let A, B be a_partition of Y; :: thesis: 'not' (Ex (Ex a,A,G),B,G) '<' 'not' (All (All a,B,G),A,G)
All ('not' (Ex a,A,G)),B,G '<' 'not' (All (All a,B,G),A,G) by Th3;
hence 'not' (Ex (Ex a,A,G),B,G) '<' 'not' (All (All a,B,G),A,G) by BVFUNC_2:21; :: thesis: verum