Let x0 of type ι be given.
Let x1 of type ι → ι → ι be given.
Let x2 of type ι → ι be given.
Let x3 of type ι be given.
Apply unknownprop_42196b468f7ee6900ff7a0764cb638961ca3510c86fc5044edb344cbf3b0bbb0 with
48567.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.