Let x0 of type ι be given.
Let x1 of type ι be given.
Apply set_ext with
binintersect x0 x1,
binintersect x1 x0 leaving 2 subgoals.
The subproof is completed by applying binintersect_com_Subq with x0, x1.
The subproof is completed by applying binintersect_com_Subq with x1, x0.