fact: Definition not_ex_all_not_rel4 := λ"nEx" λ"x" λ"y" λ"z" λ"t" λ"F" "nEx" @ (λ"f" "f" @ "x" @ "y" @ "z" @ "t" @ "F").
imports: ClassicalRealizability.Tactics ClassicalRealizability.BasicResults ClassicalRealizability.Subtyping