Definition age1_list {A} `{ageable A} := list_forall2 age.

Lemma ageN_comparable {A} {JA: Join A}{PA: Perm_alg A}{SA: Sep_alg A}{agA: ageable A}{AgeA: Age_alg A}: forall n (w1 w2 w1' w2': A), ageN n w1 = Some w1' -> ageN n w2 = Some w2' -> comparable w1 w2 -> comparable w1' w2'.