Apply unknownprop_313a3c98afcdb1d5561868421960b0f761f25c7c3efead113679cca8d598e318 with
λ x0 x1 : ι → ι → ι . ∀ x2 x3 x4 . In x4 (x1 x2 x3) ⟶ In x4 x3.
Let x0 of type ι be given.
Let x1 of type ι be given.
Let x2 of type ι be given.
Assume H0:
In x2 (Sep x0 (λ x3 . In x3 x1)).
Apply unknownprop_ba186f550679124419b8222be99b3e20dd42619ae850577f6f9edb2a83aac5a7 with
x0,
λ x3 . In x3 x1,
x2.
The subproof is completed by applying H0.