to adopt a more humanist version of natural law, such as is found in some treatises of continental natural lawyers, but was keen to stress the inherent link between reason, natural law, and the Christian (particularly the Protestant) faith. In support of the common law’s upholding of naked pactions and promises, for instance, Stair specifically cites a passage from the Book of Proverbs enjoining the listener to adhere to the ‘words of thy mouth’,160 as well as a verse in Hebrews stating that ‘he is faithful that promised’,161 the reference being to the faithfulness of divine promises. It is significant that this reference to divine fidelity to promises is used to underpin Stair’s approbation of the legal force of human promises. This is consistent with Stair’s overarching view, expressed earlier in the same title on conventional obligations, that it is God who obliges us to the performance of voluntary obligations.162 For Stair, the pattern of human fidelity to pledged performances is found in the fidelity of God to what He has promised.

Stair’s magisterial treatment of voluntary obligations gave Scots law a distinctive approach to promise that was to endure, as discussion of the modern law in Part 2 of this work will indicate.

4.  Eighteenth and nineteenth centuries

(a)  English law

There are some pre-eighteenth century indications in English law of a general concept of contract. For instance, in a case from 1550, Reniger v. Fogossa,163 it was remarked that an

agreement concerning personal things is a mutual assent of the parties, and ought to be executed with a recompence, or else ought to be so certain and sufficient, as to give an action or other remedy for recompence: and if it is not so, then it shall not be called an agreement, but rather a nude communication without effect.

This is a late usage of the term ‘recompence’, which together with causa and consideration are three terms commonly encountered until consideration alone came to dominate from around 1560 onwards. This definition of a contractual agreement, including the requirement for mutual

160 Prov. 6:1. 161 Heb. 10:23.

162‘[God] hath given that liberty in our power, that we may give it up to others, or restrain and engage it, whereby God obliges us to performance by mediation of our own will’ (I.x.1).

1631 Plowd. 1, 75 Eng. Rep. 1 (KB 1550).

performance, is remarkable given the date of its pronouncement: it was not generally until the end of the eighteenth century that contract as a distinct concept was generally conceived of separately from the various actions recognised at law, the approach of Blackstone being a good example of such later understanding.164 Prior to this point, contractual material in the few legal treatises available was scattered between treatment of the various actions, nominate contracts, and torts.165 In the early to mid-eighteenth century, there is very little of what might be called contractual theory, though occasional, somewhat unsatisfactory examples crop up.166 Where, for instance, in Gilbert’s unpublished ‘Treatise on Contract’, theoretical matters such as seriousness of intent to contract were raised, the discussion was cut short by a simple reference to consideration as demonstrating such intent without any exploration of whether other ways might conceivably demonstrate such intention.167 Similarly, Blackstone defined consideration as the ‘reason which moves the party contracting to enter into the contract’ but qualified this by referring without demurring to the civilian view that it must be ‘something mutual, reciprocal – something given in exchange’ without explaining why unreciprocated reasons for contracting cannot count.168 Such unsatisfactory references to consideration demonstrate the problem which the doctrine was to pose for the emerging will theory of contract, discussed in Chapter 2 and further below: if the will was paramount, why was it necessary in addition to demonstrate the presence of consideration, or an undertaking under seal, before a contract or a unilateral promise would be enforced?

This difficulty was perceived by the courts, and some judges attempted to restrict the ambit of consideration as a result.169 Chief among those who attempted to do so was Lord Mansfield, who famously suggested in Pillans v. van Mierop,170 a case concerning consideration in relation to a

164Blackstone defined contract as ‘an agreement upon sufficient consideration to do or not to do a particular thing’ (Commentaries, ii.442).

165Ibbetson, An Historical Introduction, p. 215.

166An example is Henry Ballow’s Treatise on Equity (1737), which contains some brief statements on contract plundered from Pufendorf, overlaid with the Common law requirement of consideration.

167The relevant passages from Gilbert’s ‘Treatise on Contract’ (BL MS Harg 265, ff 39–40,

43)are discussed by Ibbetson, An Historical Introduction, p. 237, and Swain, ‘The Classical Model of Contract’, 517.

168Blackstone, Commentaries, ii.443–4.

169See further generally on the development of the doctrine of consideration during this period, Swain, ‘The Changing Nature of the Doctrine of Consideration’.

170(1765) 3 Burr 1663. Lord Mansfield remarked that ‘I take it, that the ancient notion about the want of consideration was for the sake of evidence only: for when it is reduced into

bill of exchange, that the requirement for consideration should not apply in mercantile contracts. This general rebellion against consideration was disapproved of by the House of Lords in its later judgment in Rann v. Hughes,171 though the precise result in Pillans, excusing the need for ­consideration in cases of bills of exchange, was upheld as a matter of mercantile practice. Other situations which caused difficulty for the restrictive requirement of consideration, such as charitable promises and family arrangements, were able to be dealt with under the law of trust.172 Such solutions were not, however, as simple and as elegant as would have been a development allowing the general enforcement of a unilateral promise (including one in favour of a third party) or a gratuitous contract so long as it was seriously intended to have legal effect.

It is in the late eighteenth century that one begins to see common law writers and judges using the idea of agreement as the basis upon which to build a general notion of contract as an obligation out of the existing law of assumpsit, covenant and other actions possessing elements of ­agreement.173 Not that such definitions did not exist before, because, as is evident from the quotation from Reniger v. Fogossa above, they did, but these were isolated attempts which did not catch on. This transition to seeing contract as having a conceptual basis and force in the agreement of the parties, albeit augmented by the necessary additional requirement of consideration and occasionally writing, was solidified by the appearance of, and frequent reference to, Pothier’s Treatise, with its clear treatment of contract as a will-based obligation defined by reference to the agreement of the parties. The principles of the French law of obligations, as expounded by Pothier, provided the basis of developing the law of England in a number of fields. They provided, for instance, a basis for the emerging analysis of the contract formation procedure

writing, as in covenants, specialities, bonds etc there was no objection to the want of consideration. And the Statute of Frauds proceeded upon the same principle.’

171(1778) 4 Bro PC 27, 7 TR 350n. Lord Skynner, taking a natural law approach, did remark however that ‘It is undoubtedly true that every man is by the law of nature bound to fulfil his engagements.’

172In relation to family arrangements settled by way of trust, the natural love and affection of family members was considered adequate consideration to support the trust. The need for such consideration in trusts was dropped at the beginning of the nineteenth century. See further on these points, Ibbetson, An Historical Introduction, pp. 206–8.

173Gordley, Philosophical Origins, p. 136. Nineteenth-century treatise writers who defined contract in agreement terms included: Comyn, Law of Contracts and Promises; Colebrooke, Treatise on Obligations and Contracts; Chitty, Treatise on the Law of Contracts; Addison, Treatise on the Law of Contracts; Leake, Elements of the Law of Contracts; and Pollock, Principles of Contract at Law and in Equity .

in offer and acceptance terms.174 Pothier’s views on the entitlement of the victim of a breach of contract to damages in the performance measure also influenced the decision in the seminal English damages case Hadley v. Baxendale.175 The judgment of Alderson B in that case demonstrates some marked similarities to the views of Pothier as adopted in the Louisiana Civil Code of 1825:176 the influence of Pothier stretched not just across the English Channel but the Atlantic also.

The increasing focus in English law on the will of the parties, manifested in their agreement to contract, has been characterised as an external imposition, rather than an internal development,177 though it could surely be rejoindered that the movement away from the action of debt, with its emphasis upon the factual question of whether a debt existed, to the action of assumpsit, with its emphasis upon whether a party had willed, under a promise, to contract with another, had already represented an earlier, if rather more muted, emphasis upon the will.

Where did this leave the promise as a way of describing contract? While the idea of agreement was now in vogue, this did not obliterate promissory descriptions of contract. Sometimes agreement and promise were used as interchangeable descriptions. Thus, in Addison’s Treatise on Contracts, a contract is described as a either a promise or an agreement, though the promissory description presupposes consideration being given for the promise and thus excludes gratuitous promises.178 Moreover, in general the individual undertakings of contractual parties were still referred to as promises, albeit promises which had to be exchanged before there was a contract.

Thegrowingemphasisuponagreementmeantthat,inconceptualterms, genuinely unilateral undertakings were inevitably further squeezed out from the category of valid transactions. On the other hand, some relief for bilateral though gratuitous transactions was provided through judgments in which the courts managed to concoct consideration to suit the needs of particular cases or in which further exceptions to the rule were created. It was settled, for instance, that the courts would not question the adequacy of consideration, for, as Pollock put it, whatever ‘a man chooses to bargain for must be conclusively taken to be of some value to him’.179

177Ibbetson argues that the will theory ‘was imposed on the Common Law from the outside rather than generated from within’ (ibid., p. 221).

178Addison, Treatise on Contracts, II.i.

179Pollock, Principles of Contract (9th edn, 1921), p. 186.

This clearly prevented the development of any line of cases which would have prevented contracts being challenged as extortionate bargains, and gave the common law a character which was far removed from Aquinas’s insistence upon the just price and commutative justice.

The rise of agreement, with its focus on the will of the parties, as the basis and source of contract had a number of other effects. It posed more urgently a theoretical problem for the privity rule: if parties wanted to confer an enforceable right upon a third party, why should not such a right be recognised? Despite there being no good answer to this question, the privity rule was maintained, being reaffirmed in 1861 in Tweddle v. Atkinson.180 The notion of agreement posed a similar question to promises made under seal: if agreement were so essential, how was it that simply by using the form of a seal the need for such acceptance could be dispensed with? Again, this question was never satisfactorily answered. Will theory also produced a tendency to dress some things up as implied agreements of the parties, which ought more honestly to have been described simply as legal rules. Thus, rather than take the approach of the civil law and state that there is a rule that destruction of the subjects of a contract subsequent to formation of contract terminates the contract, courts chose to talk in terms of an implied condition of the contract that the subjects continue in existence.181 This sort of reasoning takes the idea of the will to extremes, and did much to discredit in the eyes of some the theory of contract as resting upon the human will. A further effect of the rise of will theory was that it provided the basis, when borrowed by Pollock from the German jurist Savigny,182 of the idea of the intention to create legal relations, allowing English law to explain why certain transactions, such as family arrangements, did not have effect as contracts.

The ideas of agreement and will do not provide an obvious solution to the perennially difficult question of contractual error, and in the eighteenth and early nineteenth centuries, though common law and equitable courts granted relief in cases of mistake, they did so without providing any clear conceptual basis for so doing.183 Nor, until 1860, does one find

180(1861) 1 B&S 393, 121 Eng. Rep. 762.

181See Blackburn J, in Taylor v. Caldwell (1863) 3 B & S 826.

182Ibbetson, An Historical Introduction, p. 233.

183Equity provided relief in two main types of case. There was, first, a general Chancery jurisdiction to rectify documents which did not properly reflect the underlying agreement of the parties; second, in cases of unilateral error, if there was evidence of dubious practices taking advantage of such an error, relief would be afforded. See further Ibbetson, ibid., pp. 210–11, and Gordley, Philosophical Origins, pp. 140–6.