496. Illegality or absence of consideration.

Debts founded on an illegal consideration are not provable1; but, where the consideration was in part legal, proof in part has been allowed2, and proof was allowed where a genuine debt existed, founded on an independent contract antecedent to such an illegal arrangement3.

Proof may be allowed on a contract made abroad, even though, because of some defect, such as want of registration of the contract, no remedy lies on it abroad