Let x0 of type ι be given.
Let x1 of type ι → ι be given.
Let x2 of type ι → ο be given.
Let x3 of type ι be given.
Apply unknownprop_711175fd7525b7a762509261daa887c7d457e0dd6297d76c3ee15b367548c96a with
1cd8e.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.