Let x0 of type ι be given.
Let x1 of type ι → ο be given.
Let x2 of type ι → ο be given.
Apply unknownprop_ee0b4b64aba8e6af97035d72b359ab8e1ae1e5e06024c58477c9410cad648356 with
λ x3 x4 : ι → (ι → ο) → (ι → ο) → ο . x4 x0 x1 x2 ⟶ x4 x0 x2 x1.
Assume H0:
(λ x3 . λ x4 x5 : ι → ο . ∀ x6 . In x6 x3 ⟶ iff (x4 x6) (x5 x6)) x0 x1 x2.
Let x3 of type ι be given.
Apply unknownprop_dd64fd93d8daab6216880664465dfc3db916267bc5f0c0940bb7191cc10a2c43 with
x1 x3,
x2 x3.
Apply H0 with
x3.
The subproof is completed by applying H1.