Let x0 of type ι → ι → ο be given.
Let x1 of type ι be given.
Assume H1: x0 x1 x1.
Apply canonical_elt_eq with
x0,
x1,
canonical_elt x0 x1 leaving 2 subgoals.
The subproof is completed by applying H0.
Apply canonical_elt_rel with
x0,
x1.
The subproof is completed by applying H1.