Let x0 of type ι → ο be given.
Assume H0:
not (∃ x1 . x0 x1).
Let x1 of type ι be given.
Apply unknownprop_e284d5f5a7c3a1c03631041619c4ddee06de72330506f5f6d9d6b18df929e48c with
x0 x1.
Assume H1: x0 x1.
Apply notE with
∃ x2 . x0 x2 leaving 2 subgoals.
The subproof is completed by applying H0.
Let x2 of type ο be given.
Assume H2: ∀ x3 . x0 x3 ⟶ x2.
Apply H2 with
x1.
The subproof is completed by applying H1.