Let x0 of type ι be given.
Let x1 of type ι be given.
Let x2 of type ι be given.
Let x3 of type ι be given.
Apply unknownprop_f4ff16b9b21fb43bec0dd0d2e94569d632f3d21b75932b9bcc0c1ffd4c0d62b6 with
x0,
x1,
x2,
x3,
x1 = x3 leaving 2 subgoals.
The subproof is completed by applying H0.
Assume H1: x0 = x2.
Assume H2: x1 = x3.
The subproof is completed by applying H2.