let L be Lattice; for u being Element of
for A being non empty set
for B being Finite_Subset of
for f being Function of A,the carrier of L st B <> {} & ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let u be Element of ; for A being non empty set
for B being Finite_Subset of
for f being Function of A,the carrier of L st B <> {} & ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let A be non empty set ; for B being Finite_Subset of
for f being Function of A,the carrier of L st B <> {} & ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let B be Finite_Subset of ; for f being Function of A,the carrier of L st B <> {} & ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let f be Function of A,the carrier of L; ( B <> {} & ( for x being Element of A st x in B holds
u [= f . x ) implies u [= FinMeet B,f )
assume that
A1:
B <> {}
and
A2:
for x being Element of A st x in B holds
u [= f . x
; u [= FinMeet B,f
reconsider u' = u as Element of ;
reconsider f' = f as Function of A,the carrier of (L .: ) ;
for x being Element of A st x in B holds
f' . x [= u'
by A2, Th53;
then
FinJoin B,f' [= u'
by A1, Th47;
hence
u [= FinMeet B,f
by Th54; verum