Chapter I. Promises

A SIMPLE promise is a unilateral and gratuitous contract by which the promisor binds himself to do something for another.

English law will not enforce a simple promise for which no valuable consideration was given and which was not entered into by deed. In truth, a simple promise is hardly considered to be a contract, inasmuch as this term is confined to such agreements as the law will enforce. However, in the forum of conscience a simple promise begets an obligation to fulfil it, for an honest man is faithful to his promises.

The mere expression of an intention or of a purpose to do something must be distinguished from a true promise. No new obligation is created by the former, whereas a promise imposes on the promisor a new obligation. This obligation arises from his intention to bind himself by his promise which must be made known to, and accepted by, the promisee. Until acceptance there is merely an offer, which may be revoked at will by the offeror; when the offer is accepted the promise becomes a binding contract.

There is a dispute among theologians concerning the kind and quality of the obligation imposed by a simple promise. An onerous promise for which consideration is given by the other party and mutual promises bind in justice, and consequently under pain of grievous sin in serious matter. Similarly, where the promisee has been led to rely on a promise, and would suffer serious loss unless the promise were fulfilled, the promisor will be under a grave obligation to fulfil it. Apart from these circumstances the obligation of a simple promise will depend on the intention of the promisor. If he intended to give the promisee a strict right to what was promised, he will be bound in justice; otherwise he will only be bound by the virtue of fidelity, which is a self-regarding virtue, and imposes an obligation to make the fact agree with one’s word. The virtue of fidelity of itself only binds under pain of venial sin.

A promise will cease to bind if some event takes place or becomes known subsequently which would have prevented the promisor from making the promise if it had happened or been known beforehand. For a simple promise is essentially conditional; the promisor binds himself to do something under certain suppositions and in certain circumstances; if those suppositions are not verified, or if the circumstances become changed, the obligation of the promise ceases. All the more will a promise cease to bind if what was promised becomes unlawful and wrong, or useless, or impossible. It is obvious that release by the promisee, and other causes, which are sufficient to discharge contracts according to what was said above, will also suffice to do away with the obligation of a promise.