Question Two: On Consent Required for Contract

456. The conditions required on the part of consent for contract are three, namely that consent be internal, externally manifested, and mutual:

1° Internal, namely true, deliberate, and free, because consent is an act of deliberate will, i.e., posited with that advertence of intellect and liberty of will which are required for a perfectly human act (as mortal sin is), with the intention of obligating oneself. Therefore there is excluded:

a) fictitious consent, which in reality is null; likewise consent given jokingly, or merely presumed;

b) indeliberate consent, which is not a truly human act, for example, consent given by a madman, a drunk man, one hypnotized, or a half-wit;

c) coerced consent, extorted by force or fear.

For contract is a consent of wills by which a moral obligation is undertaken and a right is transferred. But no consent of the will is given if it is not internal: for a moral obligation cannot be undertaken nor a right transferred except by a free intention or human act.

Hence 1) he who fictitiously consents, although externally he may seem seriously to pronounce words, in the external forum is presumed to have truly consented; but in reality he does not perfect a contract nor contract an obligation. Nevertheless he is bound from justice to repair the injustice inflicted on another, and if it cannot be repaired otherwise, he is even bound to fulfill what he fictitiously promised;

2. he who enters a contract with the intention of obligating himself contracts validly and is obligated, even if he has a positive will of not fulfilling, because between the two intentions there does not exist a contradiction; unless, however, he externally manifested the intention of not fulfilling, for example, "I promise the watch, but you will never have it": for this would be a sign that he does not wish to contract seriously;

3. but he who has two truly contradictory intentions, for example, of contracting and yet of not obligating himself, makes no contract;

4. yet he who intends to enter a contract as it is usually done, without having distinct knowledge of the obligation, contracts validly, because he implicitly consents to the obligation.

2° External, i.e., manifested to the other by a sign by which the internal consent becomes known to him; otherwise he is not able to know the consent. Therefore there is required a) consent expressed by sensible signs, b) communicated to the other party by at least one, so that it is manifested from the will of one for this purpose, that it may become known to the other; otherwise the consent will be held as a mere intention. Whence the manifestation of consent must be made to the other party either by the contracting party himself, or by another deputed for this; therefore it would not suffice that Peter told Paul that he wished to sell a horse to John, although John, warned by Paul, accepted the sale.

For expressing consent any external sign suitable for this suffices, by which the mind is clearly manifested; nor are words necessarily required for this; indeed silence can suffice, if from the adjuncts assent is sufficiently evident, which easily happens in gratuitous contracts as in donation, because in favorable matters silence can be held as acceptance; not so in onerous ones.

3° Mutual or reciprocal, rendered by each contracting party concerning the same object, i.e., given by one and at least implicitly accepted by the other. Namely, it is necessary that one consent to the obligation, and the other accept the consent, because before acceptance there is not had an agreement of several into the same thing. For one cannot by his own will acquire a right for another and oblige him to himself, unless he himself wills and consents.

Hence consent in some way must be simultaneous, not indeed elicited simultaneously at the same time, but existing together, insofar as the consent of one virtually or morally perseveres, not revoked, when the other expresses his consent. Whence a contract between absent persons can be perfected through a procurator or letters, or by the help of telegraph and telephone.

457. Corollaries. - From this it is easily understood:

1. That he who has offered a thing can withdraw from the offer, so long as it has not been accepted by the other; for a mere offer does not bind, except after it has been accepted;

2. likewise, that he can determine the time within which the other must consent (for example, by letter), so that, the time elapsed, the consent is withdrawn, since he now wills that it not persevere;

3. that consent, if no time has been fixed beforehand, is judged to persevere until it is revoked, or according to what law or custom shall have established;

4. that a unilateral contract of itself is perfected as soon as acceptance is manifested by an external sign, even if it has not yet been communicated and made known to the one offering, because now the consent of wills is had; - unless per accidens from positive law the communicated acceptance is required, as in solemn donation;

5. conversely, in a bilateral contract, connaturally and of itself, there is required mutual consent mutually communicated: for an obligation is not contracted nor a right yielded unless it is communicated to another; therefore where the obligation is mutual it must mutually be communicated and become known. For just as the consent of the one offering does not oblige him unless it becomes known to the other contracting party, so the consent of the one accepting does not oblige him unless it is known to the one offering; because in a bilateral contract the one accepting also offers. Whence so long as the one offering has not known the consent, he can still withdraw the offer; yet per accidens it can be established by law or by the will of the contracting parties that the contract has force from the moment of acceptance.

458. Error and deceit are opposed to deliberation of the intellect. - Error is a false judgment; speculatively it differs from ignorance, which is the mere lack of due knowledge, but practically in the present question they are equivalent, for as to effect in contracts the same thing must be said concerning each. Error is distinguished in many ways:

A. One is antecedent, if it is the cause of the contract; another is merely concomitant or incidental, which is not the cause of the contract.

B. It is substantial, or accidental:

1. Substantial error turns about the substance of the contract, i.e., about that to which consent is principally borne, whether a) about the nature or species of contract, for example, if you take letting or commodatum for sale; or b) about the substance of the thing or object, for example, gold for copper, a gem for glass, a horse for an ox, wine for oil; or c) about the primary final motive, which is principally intended; or d) about a substantial quality (which redounds into the substance), to which consent is bound, so that it is a condition without which not and limiting the consent, for example, if someone buys new wine for old, an aged mare in place of a younger one for breeding, and intends: I buy if it is so, and I do not buy unless it is old, or younger.

2. Accidental error turns about the accessories of the contract, namely a) about the secondary or impelling motive, or b) about an accidental quality to which consent is not bound. Yet this can be the motive of the contract, if it is entered into because of that quality, without that quality itself being a condition without which not of the consent; and then it is the cause of the contract, i.e., it moves to the contract, but is not principally intended, but secondarily: for example, if someone buys a horse because he thinks it is white, or wine because he judges it to be Bordeaux, without saying: I do not buy unless it is white or Bordeaux. Then the error is antecedent; but if in no way it is the cause of the contract, it is merely concomitant.

C. It is proper to the one erring and caused by no one else, and then it is simply error; or induced by another, and then it is called deceit.

459. Principles concerning a contract entered into with error. -

1. Substantial error, even merely concomitant, renders a contract invalid, because in the case the one erring does not furnish consent concerning the thing about which the contract is (a. 1110). Whence if you buy oil for wine, the contract does not have force, even if, knowing that it was oil, you would have bought it.

2. Accidental error which is not the cause of the contract, or is merely concomitant, does not render it invalid, because it has no influence on the contract.

3. Antecedent accidental error, i.e., one which in fact gives cause to the contract, renders at least in the forum of conscience a gratuitous contract invalid: for this demands a greater fullness of the voluntary, and the common good does not prevent it from being easily rescinded. Thus, for example, a donation made to someone because he is thought to be poor, or a blood relative.

Yet in practice attention must also be given to the disposition of the contracting party; for example, someone bestows a small alms on a poor man because he thinks him sober and pious and otherwise would not bestow it; yet after the fact, generally, he does not wish the donation to be void, even if the poor man is impious and drunken.

4. Accidental error which gives cause to a contract does not invalidate an onerous contract. The reason is that in an onerous contract, since favors and burdens are mutual, because of the accidental error of one, the other ought not to suffer damage; - and besides, the common good demands this, the security of commerce: for since these contracts are most frequent, if because of accidental error they could be rescinded, the whole order would be overturned and lawsuits would be multiplied unto infinity.

Many add, however: for the forum of conscience, if the matter is still intact, the deceived party is not bound to fulfill the contract, provided he renders the other party unharmed, because the tacit mind of the contracting parties is not to oblige themselves to execute the contract if they have been deceived. But this reason does not hold, because contracting parties, on account of the necessity of the common good and the security of commerce, are judged to will to consent and to renounce rescission of the contract, if only accidental errors are present, which all cannot be attended to. Besides, so it is in the external forum.

Hence: a) Error concerning quality of itself is accidental, unless the quality is intended as a condition without which not, to which consent is bound.

He who buys a red horse because he thinks it white buys validly, unless he has said: I do not buy unless it is white; conversely, a priest buying blue cloth for a cassock, which he thinks black, makes the purchase null.

b) Error concerning person of itself is substantial in gratuitous contracts, in which principally the person is attended to upon whom the benefice is conferred, and besides a greater liberty is required.

I say: of itself, because in fact the will of the one gratuitously conferring must also be attended to, especially in things of lesser moment, in small alms, in which often they intend to give absolutely, or at least do not wish restitution to be made. Conversely, in onerous contracts error concerning the person is generally accidental, for example, if you buy a book from Peter thinking it is from Paul: for then principally one's own advantage to be received from the contract is attended to; unless the person is a substantial quality, as in the purchase of a painting made by a famous painter. A fortiori the error will be substantial in matrimony, in which the person is the very matter of the contract (a. 1110).

c) Error concerning the impelling motive of the contract is accidental; conversely, if it is about the final motive, it is substantial.

Thus if someone buys a horse, falsely thinking that his own has died, the contract has force; conversely if he buys under the condition that it has died.

460. Principles concerning a contract entered into with deceit. - Deceit is a saying or deed employed to deceive another, which can be done by craftiness, frauds, machinations, fallacies, whether positively by lying, or negatively by being silent or concealing a hidden defect which ought to be revealed. Whence it is an action or omission posited so that the other may be induced into error. And therefore it includes error, and adds the injury of deception which lessens liberty; for if the other, detecting the fallacy, is not deceived, and nevertheless contracts, consent is in no way vitiated. Now:

1° Substantial deceit in the same way as error invalidates the contract, and moreover obliges one to repair the damage unjustly inflicted on the deceived party, for example, one selling worn garments as new.

2° Accidental deceit which is not the cause of the contract does not render it invalid.

3° Accidental deceit which is the cause of a gratuitous contract invalidates it.

4° Accidental deceit which is the cause of a dissoluble onerous contract, and is employed by the other contracting party, does not render the contract invalid, because it does not take away voluntary consent; but it makes it rescindable at the will of the deceived party (a. 1116-1117), because fraud ought to patronize no one.

5° Accidental deceit employed by a third party does not make the contract rescindable, unless the contracting party was a participant in the deceit; nevertheless the deceiver is obliged to repair the damage unjustly caused.

461. Violence and fear are opposed to liberty. - Physical and absolute violence, which the subject is compelled to undergo and which he wholly resists, since it renders the act altogether involuntary, renders the contract null; but it is a quasi-metaphysical case, that someone's hand be physically forced to sign a contract against his will. But if the violence is not absolute and perfect, then it is reduced to fear or moral violence. Now fear is a trepidation of mind by reason of an impending or future evil or danger. Rarely and per accidens does it so disturb the mind that it removes the use of reason; but of itself and ordinarily it does not impede.

Fear a) can be grave, absolutely or relatively, if grave damage (absolutely or relatively) and imminent is feared; or light, if only light damage is feared, or grave but not imminent;

b) can be from a necessary natural cause; or from a free cause, and then it is either justly inflicted, or on the contrary unjustly inflicted; moreover it is inflicted to extort consent or not to extort it, whether by the other party or by a third party. It makes no difference whether he who inflicts fear threatens evil to the contracting party himself or to a person closely joined to the contracting party (a. 1113).

462. Principles concerning a contract entered into with fear. -

1. Any fear whatever so disturbing the use of reason that it excuses from grave fault invalidates the contract, because it destroys consent.

2. Fear that is not unjust renders the contract neither invalid nor rescindable, unless it takes away the use of reason. A donation of money made in a fire or shipwreck to another so that he may free the donor from danger has force, or one made from fear of penalty lest the other bring the offense before a judge.

3. Grave fear unjustly inflicted, whether by a third party to extort consent or by the other contracting party for any reason, invalidates gratuitous contracts, because more perfect liberty is required for them. Thus if a son threatens his father so that he may give money.

4. Grave fear unjustly inflicted, whether by the other contracting party, or by a third party but to extort consent, does not render an onerous contract invalid, because consent remains free, but it renders it rescindable, because the consent is the fruit of injustice (a. 1109, 1111, and 1117); yet from the law of nature it seems to invalidate an indissoluble contract which binds one's whole life, such as matrimony and solemn religious profession.

Hence the purchase of a sword from fear of an enemy has force, and a promise of money made with a view to protection against an enemy; conversely, the sale of a horse from a threat of death, or a promise made to a calumniator so that he may abstain from defamation, can be rescinded.

5. Light fear in the external forum does not rescind a contract, because it is not judged to have been the cause of the contract (a. 1114); but in the internal forum, if light fear unjustly inflicted to extort consent was the sole cause of the contract, it probably renders gratuitous contracts invalid, onerous ones rescindable.

463. Observations. - 1° In civil law error, deceit, and fear must be strictly proved before a contract is annulled. Whence they give place only to rescission (a. 1117).

2° From positive law certain acts or contracts which from natural law are valid or rescindable can be invalid.

3° Briefly, the Code of Law, can. 104: "Error renders an act invalid if it turns about that which constitutes the substance of the act, or falls upon a condition without which not; otherwise it has force unless something else is provided by law; but in contracts error can give place to a rescissory action according to the norm of law."

Can. 103: "1. Acts which a person, whether physical or moral, posits from extrinsic force which he cannot resist, are held as not done.

2. Acts posited from grave and unjustly inflicted fear, or from deceit, have force, unless something else is provided by law; but they can... be rescinded by the sentence of a judge, whether at the petition of the injured party or ex officio" (cf. can. 1684-1689).