let S be non empty set ; for R being total Relation of ,
for BASSIGN being non empty Subset of
for G1, G2 being Subset of st G1 c= G2 holds
for s being Element of S st s |= Tau G1,R,BASSIGN holds
s |= Tau G2,R,BASSIGN
let R be total Relation of ,; for BASSIGN being non empty Subset of
for G1, G2 being Subset of st G1 c= G2 holds
for s being Element of S st s |= Tau G1,R,BASSIGN holds
s |= Tau G2,R,BASSIGN
let BASSIGN be non empty Subset of ; for G1, G2 being Subset of st G1 c= G2 holds
for s being Element of S st s |= Tau G1,R,BASSIGN holds
s |= Tau G2,R,BASSIGN
let G1, G2 be Subset of ; ( G1 c= G2 implies for s being Element of S st s |= Tau G1,R,BASSIGN holds
s |= Tau G2,R,BASSIGN )
set Tau1 = Tau G1,R,BASSIGN;
set Tau2 = Tau G2,R,BASSIGN;
assume A1:
G1 c= G2
; for s being Element of S st s |= Tau G1,R,BASSIGN holds
s |= Tau G2,R,BASSIGN
let s be Element of S; ( s |= Tau G1,R,BASSIGN implies s |= Tau G2,R,BASSIGN )
assume
s |= Tau G1,R,BASSIGN
; s |= Tau G2,R,BASSIGN
then
(Fid (Tau G1,R,BASSIGN),S) . s = TRUE
by Def59;
then
(chi G1,S) . s = 1
by Def64;
then
s in G1
by FUNCT_3:def 3;
then
(chi G2,S) . s = 1
by A1, FUNCT_3:def 3;
then
(Fid (Tau G2,R,BASSIGN),S) . s = TRUE
by Def64;
hence
s |= Tau G2,R,BASSIGN
by Def59; verum