Let x0 of type ι be given.
Let x1 of type ι → ο be given.
Let x2 of type ι → ι be given.
Let x3 of type ι be given.
Assume H0:
In x3 (ReplSep x0 (λ x4 . x1 x4) (λ x4 . x2 x4)).
Apply unknownprop_021a576837934491f6aaf936d4c5a9c68d45f2b77fcd13cc395cfdeec72f7dac with
x0,
x1,
x2,
x3,
False.
The subproof is completed by applying H0.