let a1, a2, v1, v2 be object ; for V, A being set st {v1,v2} c= V & v1 <> v2 & not v1 .--> a1 in A & not v2 .--> a2 in A & a1 is TypeSCNominativeData of V,A & a2 is TypeSCNominativeData of V,A holds
global_overlapping (V,A,(v1 .--> a1),(v2 .--> a2)) = (v2,v1) --> (a2,a1)
let V, A be set ; ( {v1,v2} c= V & v1 <> v2 & not v1 .--> a1 in A & not v2 .--> a2 in A & a1 is TypeSCNominativeData of V,A & a2 is TypeSCNominativeData of V,A implies global_overlapping (V,A,(v1 .--> a1),(v2 .--> a2)) = (v2,v1) --> (a2,a1) )
set D1 = v1 .--> a1;
set D2 = v2 .--> a2;
assume that
A1:
{v1,v2} c= V
and
A2:
v1 <> v2
and
A3:
( not v1 .--> a1 in A & not v2 .--> a2 in A )
and
A4:
( a1 is TypeSCNominativeData of V,A & a2 is TypeSCNominativeData of V,A )
; global_overlapping (V,A,(v1 .--> a1),(v2 .--> a2)) = (v2,v1) --> (a2,a1)
( v1 in V & v2 in V )
by A1, ZFMISC_1:32;
then A5:
( naming (V,A,v1,a1) = v1 .--> a1 & naming (V,A,v2,a2) = v2 .--> a2 )
by A4, Def13;
A6:
{v1} \ {v2} = {v1}
by A2, ZFMISC_1:14;
{v1} misses {v2}
by A2, ZFMISC_1:11;
hence (v2,v1) --> (a2,a1) =
(v2 .--> a2) \/ ((v1 .--> a1) | ((dom (v1 .--> a1)) \ (dom (v2 .--> a2))))
by A6, FUNCT_4:30, PARTFUN1:56
.=
global_overlapping (V,A,(v1 .--> a1),(v2 .--> a2))
by A3, A5, Th64
;
verum