Let x0 of type ι be given.
Let x1 of type ι be given.
Apply unknownprop_b777a79c17f16cd28153af063df26a4626b11c1f1d4394d7f537c11837ab0962 with
In x0 x1.
Assume H1:
not (In x0 x1).
Apply notE with
nIn x0 x1 leaving 2 subgoals.
The subproof is completed by applying H0.
Apply unknownprop_3ec14466ed0aaeda1a16471c7d77d44ee3048fda5177bf110947a6b334a3fea0 with
x0,
x1.
The subproof is completed by applying H1.