Let x0 of type ι → ι be given.
Let x1 of type ι → ο be given.
Assume H0: ∀ x2 . x1 x2 ⟶ x1 (x0 x2).
Let x2 of type ι be given.
Assume H1: x1 x2.
Apply unknownprop_1614b543c6d96eeda0a488900213094a8fd1c045e7cd1981f3f7be2de773b0b2 with
x0,
x1,
ChurchNum_ii_2 ChurchNum2 x0 x2 leaving 2 subgoals.
The subproof is completed by applying H0.
Apply unknownprop_1614b543c6d96eeda0a488900213094a8fd1c045e7cd1981f3f7be2de773b0b2 with
x0,
x1,
x2 leaving 2 subgoals.
The subproof is completed by applying H0.
The subproof is completed by applying H1.