Let x0 of type ((ι → ο) → ο) → ο be given.

Let x1 of type (((ι → ο) → ο) → ο) → ο be given.

Assume H0: x1 x0.

Let x2 of type ο be given.

Assume H1: ∀ x3 : ((ι → ο) → ο) → ο . and (a327b.. x0 = a327b.. x3) (x1 x3) ⟶ x2.

Apply H1 with x0.

Apply unknownprop_389e2fb1855352fcc964ea44fe6723d7a1c2d512f04685300e3e97621725b977 with a327b.. x0 = a327b.. x0, x1 x0 leaving 2 subgoals.

Let x3 of type ((((ι → ο) → ο) → ο) → ο) → ((((ι → ο) → ο) → ο) → ο) → ο be given.

Assume H2: x3 (a327b.. x0) (a327b.. x0).

The subproof is completed by applying H2.

The subproof is completed by applying H0.

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Proofgold Proof