let A be non empty set ; :: thesis: for f being monotone UnOp of (BooleLatt A) ex g being V202() Function of (bool A),(bool A) st lfp A,g = lfp f
let f be monotone UnOp of (BooleLatt A); :: thesis: ex g being V202() Function of (bool A),(bool A) st lfp A,g = lfp f
the carrier of (BooleLatt A) = bool A
by LATTICE3:def 1;
then reconsider g = f as V202() Function of (bool A),(bool A) by Th49;
take
g
; :: thesis: lfp A,g = lfp f
reconsider lf = lfp f as Subset of A by LATTICE3:def 1;
lfp f is_a_fixpoint_of f
by Th44;
then A1:
lfp A,g c= lf
by Th10;
reconsider lg = lfp A,g as Element of (BooleLatt A) by LATTICE3:def 1;
lg is_a_fixpoint_of f
by Th6;
then
lfp f [= lg
by Th46;
then
lf c= lg
by LATTICE3:2;
hence
lfp A,g = lfp f
by A1, XBOOLE_0:def 10; :: thesis: verum