let I be non empty set ; for M being ManySortedSet of I
for X being Subset of (EqRelLatt M)
for X1 being SubsetFamily of [|M,M|] st X1 = X & not X is empty holds
for a, b being Equivalence_Relation of M st a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) holds
a = b
let M be ManySortedSet of I; for X being Subset of (EqRelLatt M)
for X1 being SubsetFamily of [|M,M|] st X1 = X & not X is empty holds
for a, b being Equivalence_Relation of M st a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) holds
a = b
let X be Subset of (EqRelLatt M); for X1 being SubsetFamily of [|M,M|] st X1 = X & not X is empty holds
for a, b being Equivalence_Relation of M st a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) holds
a = b
let X1 be SubsetFamily of [|M,M|]; ( X1 = X & not X is empty implies for a, b being Equivalence_Relation of M st a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) holds
a = b )
assume that
A1:
X1 = X
and
A2:
not X is empty
; for a, b being Equivalence_Relation of M st a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) holds
a = b
let a, b be Equivalence_Relation of M; ( a = meet |:X1:| & b = "/\" (X,(EqRelLatt M)) implies a = b )
reconsider a9 = a as Element of (EqRelLatt M) by MSUALG_5:def 5;
assume that
A3:
a = meet |:X1:|
and
A4:
b = "/\" (X,(EqRelLatt M))
; a = b
then
a9 is_less_than X
;
hence
a = b
by A4, A5, LATTICE3:34; verum