Let x0 of type ι → ι be given.
Let x1 of type ι → ι be given.
Assume H0:
not (x0 = x1).
Assume H1:
∀ x2 . not (x0 x2 = x1 x2) ⟶ False.
Apply notE with
x0 = x1 leaving 2 subgoals.
The subproof is completed by applying H0.
Apply functional extensionality with
x0,
x1.
Let x2 of type ι be given.
Apply unknownprop_b777a79c17f16cd28153af063df26a4626b11c1f1d4394d7f537c11837ab0962 with
x0 x2 = x1 x2.
Assume H2:
not (x0 x2 = x1 x2).
Apply H1 with
x2.
The subproof is completed by applying H2.