Article — Noldin, Summa of Moral Theology
Article Fifth. On the Cause of Consent
538. What and of how many kinds it is. 1. The cause of a contract or of consent is called the reason because of which one transfers a right to another. This cause in gratuitous contracts is the will of doing good; in onerous contracts it is the utility to be received from the thing concerning which the contract is made.
- A twofold cause of contract is distinguished: one motive, which proximately determines the consent; another impulsive, which does not proximately determine the consent, but is either its occasion or only moves somewhat to the consent. The motive cause is also called the principal and primary motive; and the impulsive cause is called the secondary and impulsive motive of the contract. The former especially moves the contracting party, and therefore when it exists the contract is valid, and when it is lacking the contract is invalid. The latter does not suffice of itself for determining the will, but indeed moves the will already determined, yet only so that it may contract more willingly; wherefore, even if it is lacking, the contract nevertheless exists.
The payment of a legacy which someone made while falsely thinking that it had been established by his father does not have force, because the motive cause is lacking, namely the debt enjoined by the father. The purchase of a field which someone made while falsely thinking that a treasure was hidden in it has force, because only the impulsive cause is lacking, namely the hope of finding the treasure. Whether in a particular case the cause was motive or impulsive can be known from the contracting party alone.
Whether contracts entered from a base cause are valid: I give you one hundred so that you kill Peter; or under a base condition: I give you one hundred if you kill Peter.
alpha. While the contract has not yet been fulfilled, neither contracting party is obligated to fulfill it; indeed each is bound to withdraw from the contract, and if the price had already been paid before the base action was placed, it would have to be restored, because it is not permitted to place the condition under which the price was paid.
beta. But when the contract has already been fulfilled, that is, once the dishonorable action has been placed, the other contracting party must pay the price, and the other can licitly demand and retain it.1
alpha. This opinion, which is common among authors, can be called certain and is confirmed in this way. A contract concerning a base object or from a base cause is a promise concerning an evil thing, which is illicit and invalid; but if the other truly furnishes the evil work, by that very fact a new unnamed contract arises, I do that you may give, so that the one promising is bound to pay the price from justice by force of this unnamed contract. Namely, he who executes the base work furnishes something which is estimable by price: for the work is burdensome and dangerous to one contracting party, but useful or delightful to the other; and he furnishes it with the intention that the one promising be bound to pay the promised price. But this one by the base promise itself consents to the obligation of paying the price if the work has been furnished in his favor. But this contract, which is distinct from the base contract and is perfected when the base work is perpetrated, is indeed illicit insofar as it supposes a base deed, but in itself is licit and valid: for the matter of the contract is not the action insofar as it is evil, but on the one hand the material work placed at the service of another, and on the other the price to be paid for the work furnished.2
beta. And these things indeed hold by natural law; but positive laws now declare invalid contracts whose motive cause is illicit.3 Now those invalidating laws, since they were established for the common good in penalty of an offense, oblige in conscience. Therefore if it is certainly established that the law renders these contracts void even as to payment of the price after the base work has been furnished, there is no obligation of paying the price for the evil action truly furnished. The only question is whether these laws void the contracts before or after the sentence of a judge. If from the tenor of the law the former is established, the one promising cannot be obligated to pay the price, and the other can neither demand nor retain it; but if this is not established (as generally happens), in practice before the sentence of a judge favor must be given to the possessor, that is, to him who promised, if he has not yet given, or to him who did the base work, if he has already received.4
gamma. With contracts concerning a base thing one must not confuse cases in which, without any agreement, something is given to another with the intention that he be enticed to a dishonorable action; for example, if a master gives gifts to a maidservant in order to draw her to base things. For these are gratuitous gifts which need not be restored, even if the dishonorable action did not follow. Yet restitution is to be advised where there must be fear that base love is fostered by retention of the gift.5
1 The Sacred Penitentiary, Apr. 23, 1822, declared that a prostitute can demand the price of prostitution and retain it.
2 Cf. Lehmkuhl I, n. 1052 ss.; Vermeersch n. 292 ss.; Zeitschrift fur k. Th., 1909, p. 480 ff.
3 C.A. Section 878. Yet Section 1174 establishes that what someone knowingly already gave for executing an illicit thing can no longer be reclaimed; C.G. Sections 138 and 817.
4 Cf. D'Annibale, Summula theolog. mor.^5 (Rome: Desclee, 1908), II, n. 301; St. Alphonsus, n. 712.
5 Cf. St. Alphonsus, n. 712; Holzmann, Theol. mor., t. 4, n. 689.