Question I: What a contract is, and of how many kinds

CONTRACT is properly defined by Ulpian in Leg. Labeo, ff. de verborum signific., where he says: It is an obligation from one side and the other: the Doctors supply: Arising from the will and agreement of the parties. That is, a contract is a pact from which arises an obligation on both sides. Thus St. Bonaventure takes the definition of contract in 4. dist. 27 passim, and dist. 29 quaest. 2, in fundamentis, in corpore, et ad argumenta.

THIS definition, or description, is handed down by its effect, that is, by the mutual obligation which results from the pact of the parties, as St. Bonaventure observes, in the places cited; wherefore it is rather a causal definition than a formal one, as Bonaventure notes, in dist. 3. de contract. quaest. 1. puncto 1.

Yet it can be said, with St. Bonaventure, 4. dist. 27. quaest. 2., that the obligation, or bond, of contract is taken in the definition according to the cause in intention, insofar namely as the will, intending the expressly drawn obligation, from both sides is the contract; and then the definition will be essential through the formal cause, which Suarez also observes, Lib. primo de voto, cap. 13. num. 11., and Fagundez, Lib. 1. cap. 2.

From these you have that a pact extends more widely than strict contract. A pact is defined: It is the agreement and consent of two or more into the same thing. For in a pact an obligation can result from one side only, as in donations, where only the donor is obligated to give, not the donee to accept. Then, by force of a bare pact, a promise arises in the order of truth, not of justice; but in a contract an obligation of commutative justice arises, as St. Bonaventure teaches, 4. dist. 29. loco citato.

HENCE also you have by what name certain conventions are called in which results the obligation of one party or parties from some office, for example of a Tutor, Curator, or steward; these, however, are called quasi-contracts. The definition is given by Fagundez, de contract. Lib. 1. cap. 2.: A quasi-contract is an obligation by which someone is bound to another not from any contract or wrongdoing, but from some office or act lawful and honest, even though no express will of either party intervenes.

THEREFORE IT IS MOST CERTAIN that in contracts the consent of both parties is necessary, as the Holy Doctor often repeats, in 4. dist. 27. 28. et 29., Molina, Tom. 2. disp. 254., Lessius, Tom. 1. Lib. 2. cap. 17. dub. 2., Azor., part. 3. lib. 6. cap. 2., Bonacina, de contract. in genere, disp. 3. quaest. 1. puncto 2., Sanchez, Lib. primo de matrim. disp. 8. et lib. 4. decal. cap. 1., Suarez, tomo 2. de relig. lib. 2. de iuram. cap. 7., Fagundez, Lib. 1. cap. 2. num. 2., Tannerus, disp. 4. quaest. 7. dub. 1.

THERE ARE MANY kinds of contracts, as St. Bonaventure teaches, in the places cited, and in speculo animae, cap. 1. 2. et 4.

THEY ARE DIVIDED into Nominated and Unnominated. A nominated contract is one which has its proper name, as Lease, Hiring, Sale, Deposit, and Settlement.

UNNOMINATED contracts are those which lack a proper name, and they are reduced almost to these four modes: Do, ut des, e.g. Give me a horse, that you give me wheat. Do, ut facias: I give you wheat, that you till my field. Facio, ut facias, e.g. I till your field, that you build me a house. Facio, ut des. I till your field, that you give me wheat. These are treated in L. ge. Naturalis, ff. de praescriptis verbis. But these contracts are regulated according to the Nominated ones.

NOMINATED contracts are divided into contracts of good faith and of strict law.

CONTRACTS OF GOOD FAITH are those in which Judges decide not so much in the rigor of law and pact as from equity and good.

CONTRACTS OF STRICT LAW are those in which judges proceed by the rigor of law.

CONTRACTS OF GOOD FAITH are Purchase, Sale, Lease, Hiring, Procuratorship, or Mandate for the management of affairs, Deposit, Loan for use, Insurance, Partnership, Guardianship, Pledging, the right of dividing an estate among heirs, division of common property among several. Likewise when a thing is given to someone that he may return it, or its price. But the other contracts, as Emphyteusis, quaest. 5. num. 32., and Exchanges, are of strict law, as Rebellius teaches, 2. part. lib. 1. quaest. 2., Molina, Tom. 2. de iustitia, disput. 259., Valascus, de emphyt. quaest. 5., Fagundez, cap. 1. num. 8., who, against others, approve this division not only in the external forum but also in the forum of the soul.

BUT WHETHER betrothals ought to be reckoned among contracts of strict law; Sanchez, Lib. 1. de matrim. disp. 64. num. 3., supposes, as certain, that they are of good faith, from which it can be inferred that betrothals to which fraud gave occasion are invalid, because contracts of good faith to which fraud gave occasion are invalid; and this seems to be the mind of St. Bonaventure, in 4. dist. 27. dub. 2. litterali.

NOMINATED contracts are divided into Onerous and Lucrative. Lucrative are those in which something is remitted, promised, or given to someone without any burden or compensation of justice, but merely gratuitously, as donation, acceptilation, loan for use, as to the use of the thing; for although the borrower is bound to restore the thing, yet the use is liberal. Onerous contracts are those on which a burden falls on both sides, as in purchase. To this division are reduced contracts Respective and non-Respective. Respective are those in which obligation results from both sides, and they are proper contracts. Non-respective, in which obligation results from one side only, are less proper, as stipulation and promise.

IF contract be taken for pact, it is divided into Bare and Clothed. A bare pact is one in which only the agreement of the parties intervenes and nothing further has been done, and no other foundation is present. Clothed is that which is strengthened by solemnities, or is invested with some circumstance in which it is confirmed by civil law.

IT IS CLOTHED, moreover, in six ways. First in the thing, if it be fulfilled at least on one side. Secondly by words, if stipulation is added. Thirdly by writing, as if by a letter you acknowledged that satisfaction had already been made to you, even if it had not been made, which is called Acceptilation. Fourthly by the specific name of contract; by which reason all contracts which are perfected by consent, indeed all nominated contracts, are clothed, if they are perfect in their kind. Fifthly by oath. Sixthly by coherence with some clothed contract, as if I sell you a house for a thousand gold pieces with the pact that I may still dwell in it, and give you this garment for my dwelling; this accessory pact of itself is a bare pact, yet because it coheres with the sale it is also clothed, because the accessory follows the nature of the principal.

IT IS DIVIDED also into a Guarentigium contract and a non-Guarentigium one.

A GUARENTIGIUM is one that has execution ready at hand, because of the oath placed in it, or a hypothec, or a public instrument in which the right of executing it is conceded without awaiting the judge's sentence.

A NON-GUARENTIGIUS is one that lacks these securities. So Molina, tract. 1. disp. 71., Lessius, Lib. 2. c. 28. dub. 1., Fagundez, cap. 1. in fine.