Reply to Objection 1: A favor may be bestowed on a person without injustice, but a person cannot be damnified except for a fault. Hence an illegitimate child can be legitimized rather than "vice versa"; for although a legitimate son is sometimes deprived of his inheritance on account of his fault, he is not said to be illegitimate, because he was legitimately begotten.
Reply to Objection 2: Illegitimate intercourse has an inherent inseparable defect whereby it is opposed to the law: and consequently it cannot be legitimized. Nor is there any comparison with an illegitimate child who has no such defect.