Let x0 of type ι be given.
Let x1 of type (ι → ο) → ο be given.
Let x2 of type ι → ι be given.
Let x3 of type ι → ο be given.
Apply unknownprop_7bd5c275d46b9a5be91f11682f03b42077811bd33935a9a62d9979c81a223851 with
c7ccc.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.