Let x0 of type ι be given.
Let x1 of type (ι → ο) → ο be given.
Let x2 of type ι → ι → ι be given.
Let x3 of type ι → ο be given.
Apply unknownprop_ef9e8726be461a32132c34e9ddcd61fc1c1606d734a64b812d5c281da6f18aab with
d7d7e.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.