let L be Lattice; for u being Element of L
for A being non empty set
for B being Finite_Subset of A
for f being Function of A,the carrier of L st ( for x being Element of A st x in B holds
f . x = u ) & B <> {} holds
FinMeet B,f = u
let u be Element of L; for A being non empty set
for B being Finite_Subset of A
for f being Function of A,the carrier of L st ( for x being Element of A st x in B holds
f . x = u ) & B <> {} holds
FinMeet B,f = u
let A be non empty set ; for B being Finite_Subset of A
for f being Function of A,the carrier of L st ( for x being Element of A st x in B holds
f . x = u ) & B <> {} holds
FinMeet B,f = u
let B be Finite_Subset of A; for f being Function of A,the carrier of L st ( for x being Element of A st x in B holds
f . x = u ) & B <> {} holds
FinMeet B,f = u
let f be Function of A,the carrier of L; ( ( for x being Element of A st x in B holds
f . x = u ) & B <> {} implies FinMeet B,f = u )
reconsider f9 = f as Function of A,the carrier of (L .: ) ;
A1:
FinJoin B,f9 = FinMeet B,f
;
assume
( ( for x being Element of A st x in B holds
f . x = u ) & B <> {} )
; FinMeet B,f = u
hence
FinMeet B,f = u
by A1, SETWISEO:33; verum