It may frequently happen that a good man ought to think himself bound, from a sacred and conscientious regard to the general rules of justice, to perform many things which it would be the highest injustice to extort from him, or for any judge or arbiter to impose upon him by force. To give a trite example; a highwayman, by the fear of death, obliges a traveller to promise him a certain sum money. Whether such a promise, extorted in this manner by force, ought to be regarded as obligatory, is a question that has been much debated.
If we consider it merely as a question of jurisprudence, the decision can admit of no doubt. It would be absurd to suppose that the highwayman can be entitled to use force to constrain the other to perform. To extort the promise was a crime which deserved the highest punishment, and to extort the performance would only be adding a new crime to the former. He can complain of no injury who has been only deceived by the person by whom he might justly have been killed. To suppose that a judge ought to enforce the obligation of such promises, or that the magistrate ought to allow them to sustain action at law, would be the most ridiculous of all absurdities. If we consider this question, therefore, as a question of jurisprudence, we can be at no loss about the decision.
But if we consider it as a question of casuistry, it will not be so easily determined. Whether a good man, from a conscientious regard to that most sacred rule of justice, which commands the observance of all serious promises, would not think himself bound to perform, is at least much more doubtful. That no regard is due to the disappointment of the wretch who brings him into this situation, that no injury is done to the robber, and consequently that nothing can be extorted by force, will admit of no sort of dispute. But whether some regard is not, in this case, due to his own dignity and honour, to the inviolable sacredness of that part of his character which makes him reverence the law of truth and abhor everything that approaches to treachery and falsehood, may, perhaps, more reasonably be made a question. The casuists accordingly are greatly divided about it. One party, with whom we may count Cicero among the ancients, among the moderns, Puffendorf, Barbeyrac his commentator, and above all the late Dr. Hutcheson, one who in most cases was by no means a loose casuist, determine, without any hesitation, that no sort of regard is due to any such promise, and that to think otherwise is mere weakness and superstition. Another party, among whom we may reckon (St. Augustine, La Placette) some of the ancient fathers of the church, as well as some very eminent modern casuists, have been of another opinion, and have judged all such promises obligatory.
If we consider the matter according to the common sentiments of mankind, we shall find that some regard would be thought due even to a promise of this kind; but that it is impossible to determine how much, by any general rule that will apply to all cases without exception. The man who was quite frank and easy in making promises of this kind, and who violated them with as little ceremony, we should not choose for our friend and companion. A gentleman who should promise a highwayman five pounds and not perform, would incur some blame. If the sum promised, however, was very great, it might be more doubtful what was proper to be done. If it was such, for example, that the payment of it would entirely ruin the family of the promiser, if it was so great as to be sufficient for promoting the most useful purposes, it would appear in some measure criminal, at least extremely improper, to throw it for the sake of a punctilio into such worthless hands. The man who should beggar himself, or who should throw away an hundred thousand pounds, though he could afford that vast sum, for the sake of observing such a parole with a thief, would appear to the common sense of mankind, absurd and extravagant in the highest degree. Such profusion would seem inconsistent with his duty, with what he owed both to himself and others, and what, therefore, regard to a promise extorted in this manner, could by no means authorise. To fix, however, by any precise rule, what degree of regard ought to be paid to it, or what might be the greatest sum which could be due from it, is evidently impossible. This would vary according to the characters of the persons, according to their circumstances, according to the solemnity of the promise, and even according to the incidents of the rencounter: and if the promiser had been treated with a great deal of that sort of gallantry, which is sometimes to be met with in persons of the most abandoned characters, more would seem due than upon other occasions. It may be said in general, that exact propriety requires the observance of all such promises, wherever it is not inconsistent with some other duties that are more sacred; such as regard to the public interest, to those whom gratitude, whom natural affection, or whom the laws of proper beneficence should prompt
