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) & ( 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; :: thesis: verum