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The historical development of promissory ideas in the law

Having considered in the last chapter the idea of a promise as an obligation,­ as well as competing theories for the moral force of promissory obligations, in this chapter an historical analysis will be offered of the role which promise has played in the legal enforcement of voluntary obligations. As this analysis will disclose, after showing early signs of performing a likely major role in obligational theory and practice, promise dwindled in importance from the seventeenth century. Such a development might have surprised earlier generations of jurists: promissory actions played a central role in both Roman law (in the stipulatio) and the Common law (in the action of assumpsit), and promise was a core idea in the scheme of voluntary obligations of the scholastics, late scholastics, and canonists. Rather, however, than continuing to occupy this central role, promise pollinated contract, enriching it with the idea of the universal enforceability of contracts (expressed in the maxim pacta sunt servanda), and provided an analytical tool for explaining the nature of contract formation as an exchange of conditional promises. Having performed these roles, promise was eclipsed by the flowering of the very obligation of contract which it had enriched. What was left of promise at the end of this process was a continued independent existence in only one major Western legal system,1 and an explanatory2 and supplementary­ 3 function in the others. It will be suggested in this chapter that the eclipsing of promise was a great loss to Western legal systems: many transactions are best analysed in promissory terms, contract providing a second best and not wholly apt analysis.

1That being Scots Law.

2Explanatory in that it came to be used as one explanation for the nature of contract (as an exchange of conditional promises).

3Supplementary in the sense that the idea of promise was used in exceptional cases to explain circumstances which orthodox contract law found hard to explain, such as the offer of reward, the rights of a third party under contract, or the contract under seal (essentially a contract in promissory form).

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