deffunc H1( set , Function of (Inf_seq S),BOOLEAN ) -> Element of BOOLEAN = Next_univ $1,$2;
consider IT being set such that
A1: IT in ModelSP (Inf_seq S) and
A2: for t being set st t in Inf_seq S holds
( H1(t, Fid f,(Inf_seq S)) = TRUE iff (Fid IT,(Inf_seq S)) . t = TRUE ) from MODELC_1:sch 2();
take IT ; :: thesis: ( IT is Element of ModelSP (Inf_seq S) & ( for t being set st t in Inf_seq S holds
( Next_univ t,(Fid f,(Inf_seq S)) = TRUE iff (Fid IT,(Inf_seq S)) . t = TRUE ) ) )

thus ( IT is Element of ModelSP (Inf_seq S) & ( for t being set st t in Inf_seq S holds
( Next_univ t,(Fid f,(Inf_seq S)) = TRUE iff (Fid IT,(Inf_seq S)) . t = TRUE ) ) ) by A1, A2; :: thesis: verum