let U1 be non empty set ; :: thesis: for S being Language
for R being Equivalence_Relation of U1
for phi being 0wff string of S
for i being b1,U1 -interpreter-like b2 -respecting Function st (S -firstChar) . phi <> TheEqSymbOf S holds
(i quotient R) -AtomicEval phi = i -AtomicEval phi

let S be Language; :: thesis: for R being Equivalence_Relation of U1
for phi being 0wff string of S
for i being S,U1 -interpreter-like b1 -respecting Function st (S -firstChar) . phi <> TheEqSymbOf S holds
(i quotient R) -AtomicEval phi = i -AtomicEval phi

let R be Equivalence_Relation of U1; :: thesis: for phi being 0wff string of S
for i being S,U1 -interpreter-like R -respecting Function st (S -firstChar) . phi <> TheEqSymbOf S holds
(i quotient R) -AtomicEval phi = i -AtomicEval phi

let phi be 0wff string of S; :: thesis: for i being S,U1 -interpreter-like R -respecting Function st (S -firstChar) . phi <> TheEqSymbOf S holds
(i quotient R) -AtomicEval phi = i -AtomicEval phi

let i be S,U1 -interpreter-like R -respecting Function; :: thesis: ( (S -firstChar) . phi <> TheEqSymbOf S implies (i quotient R) -AtomicEval phi = i -AtomicEval phi )
set TT = AllTermsOf S;
set E = TheEqSymbOf S;
set p = SubTerms phi;
set F = S -firstChar ;
set r = (S -firstChar) . phi;
set n = abs (ar ((S -firstChar) . phi));
set U = Class R;
set I = i quotient R;
set UV = (i quotient R) -TermEval ;
set N1 = (abs (ar ((S -firstChar) . phi))) -tuples_on U1;
set V = (i quotient R) -AtomicEval phi;
set uv = i -TermEval ;
set v = i -AtomicEval phi;
set f = ((i quotient R) ===) . ((S -firstChar) . phi);
set G = (i quotient R) . ((S -firstChar) . phi);
set g = i . ((S -firstChar) . phi);
set d = (Class R) -deltaInterpreter ;
Z0: ( SubTerms phi in (abs (ar ((S -firstChar) . phi))) -tuples_on (AllTermsOf S) & dom ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) = (abs (ar ((S -firstChar) . phi))) -tuples_on (AllTermsOf S) & dom ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) = (abs (ar ((S -firstChar) . phi))) -tuples_on (AllTermsOf S) ) by FOMODEL0:16, FUNCT_2:def 1;
assume C0: (S -firstChar) . phi <> TheEqSymbOf S ; :: thesis: (i quotient R) -AtomicEval phi = i -AtomicEval phi
then C1: (i quotient R) -AtomicEval phi = ((i quotient R) . ((S -firstChar) . phi)) . (((i quotient R) -TermEval) * (SubTerms phi)) by FOMODEL2:14
.= ((i quotient R) . ((S -firstChar) . phi)) . (((R -class) * (i -TermEval)) * (SubTerms phi)) by Lm32
.= ((i quotient R) . ((S -firstChar) . phi)) . (((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) . (SubTerms phi)) by Lm22
.= (((i quotient R) . ((S -firstChar) . phi)) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval)))) . (SubTerms phi) by Z0, FUNCT_1:13 ;
reconsider o = (S -firstChar) . phi as Element of OwnSymbolsOf S by C0, FOMODEL1:15;
set gg = i . o;
set GG = (i quotient R) . o;
reconsider ggg = i . o as (abs (ar ((S -firstChar) . phi))) -placesOf R, id BOOLEAN -respecting Function of ((abs (ar ((S -firstChar) . phi))) -tuples_on U1),BOOLEAN by DefCompatible2, FOMODEL2:def 2;
set F = ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN));
reconsider P = peeler BOOLEAN as Function ;
reconsider nuisance1 = ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN)), nuisance2 = (abs (ar ((S -firstChar) . phi))) -tuple2Class R, nuisance3 = P as Relation ;
reconsider RR = R -class as Relation of U1,(Class R) ;
Z2: (i quotient R) . o = (i . o) quotient R by DefQuot3b
.= (peeler BOOLEAN) * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * ((abs (ar ((S -firstChar) . phi))) -tuple2Class R)) by DefQuot2 ;
C4: ((abs (ar ((S -firstChar) . phi))) -tuple2Class R) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) = (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class) * ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval))
proof
set x = (abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval));
E2: ((abs (ar ((S -firstChar) . phi))) -tuple2Class R) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) = (((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * ((abs (ar ((S -firstChar) . phi))) -placesOf RR)) * (((abs (ar ((S -firstChar) . phi))) -placesOf (RR ~)) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class)) by Lm20
.= ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) * (((abs (ar ((S -firstChar) . phi))) -placesOf (RR ~)) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class))) by RELAT_1:36
.= ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * ((((abs (ar ((S -firstChar) . phi))) -placesOf RR) * ((abs (ar ((S -firstChar) . phi))) -placesOf (RR ~))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class)) by RELAT_1:36
.= ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * ((((abs (ar ((S -firstChar) . phi))) -placesOf RR) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) ~)) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class)) by Lm19 ;
((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * ((((abs (ar ((S -firstChar) . phi))) -placesOf RR) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) ~)) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class)) = (((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) ~))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class) by RELAT_1:36
.= ((((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) * ((abs (ar ((S -firstChar) . phi))) -placesOf RR)) * (((abs (ar ((S -firstChar) . phi))) -placesOf RR) ~)) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class) by RELAT_1:36 ;
hence ((abs (ar ((S -firstChar) . phi))) -tuple2Class R) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) = (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class) * ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) by E2, FOMODEL0:27; :: thesis: verum
end;
(P * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * ((abs (ar ((S -firstChar) . phi))) -tuple2Class R))) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval))) = P * (((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * ((abs (ar ((S -firstChar) . phi))) -tuple2Class R)) * ((abs (ar ((S -firstChar) . phi))) -placesOf ((R -class) * (i -TermEval)))) by RELAT_1:36
.= P * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * ((((abs (ar ((S -firstChar) . phi))) -placesOf R) -class) * ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)))) by C4, RELAT_1:36 ;
then (i quotient R) -AtomicEval phi = (P * (((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class)) * ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)))) . (SubTerms phi) by C1, Z2, RELAT_1:36
.= ((P * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class))) * ((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval))) . (SubTerms phi) by RELAT_1:36
.= (P * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class))) . (((abs (ar ((S -firstChar) . phi))) -placesOf (i -TermEval)) . (SubTerms phi)) by Z0, FUNCT_1:13
.= (P * ((ggg quotient (((abs (ar ((S -firstChar) . phi))) -placesOf R),(id BOOLEAN))) * (((abs (ar ((S -firstChar) . phi))) -placesOf R) -class))) . ((i -TermEval) * (SubTerms phi)) by Lm22
.= (P * (((id BOOLEAN) -class) * ggg)) . ((i -TermEval) * (SubTerms phi)) by Lm27
.= ((P * ((id BOOLEAN) -class)) * ggg) . ((i -TermEval) * (SubTerms phi)) by RELAT_1:36
.= ((id BOOLEAN) * ggg) . ((i -TermEval) * (SubTerms phi)) by Lm26
.= ggg . ((i -TermEval) * (SubTerms phi)) by FUNCT_2:17
.= i -AtomicEval phi by FOMODEL2:14 ;
hence (i quotient R) -AtomicEval phi = i -AtomicEval phi ; :: thesis: verum