Proofgold Proof

pf
Let x0 of type ι → ι → ο be given. Let x1 of type ι → ι be given. Let x2 of type ι be given. Assume H0: and (x0 x2 x2) (x2 = canonical_elt_def x0 x1 x2). Apply andEL with x0 x2 x2, x2 = canonical_elt_def x0 x1 x2. The subproof is completed by applying H0. ■