Section — Wouters, Manual of Moral Theology

§ II. On the Subject of Contract

830.

I. Persons capable or incapable. Capable of contracting are all who enjoy the full use of reason, unless they are excluded by ecclesiastical or civil law. The reason is that the full use of reason suffices for giving consent, by which a contract is constituted. Which persons are excluded by ecclesiastical law, canonists teach; which by civil law, see in the civil Code.

831.

II. Consequences of incapacity. Contracts entered into by one civilly incapable are commonly made void in this sense, that they can be rescinded by the judge in a case in which rescission is legitimately sought. Civil law should teach who can seek rescission.

Corollary I. Incapable persons - and others who can seek rescission - if they have acted in good faith, licitly seek rescission of the contract. Nevertheless, it is not equitable that rescission of the contract be sought if there is question of contracts which commonly are entered into with an incapable person even by prudent and upright persons. The aforesaid can likewise use an exception, that is, deny execution of the contract; nor does the natural validity of the contract stand against this assertion, because no one is bound to furnish what he can immediately recover by petitioning the judge for rescission of the contract. If they have acted in bad faith - for example if the incapable person pretended himself capable, or contracted with the intention of later seeking rescission of the contract with damage to the other - they are bound at least to repair the injury inflicted on the other.

Corollary II. One who has contracted with an incapable person can stand by the contract until the right of the incapable person is legitimately urged.