A treatise of human nature: being an attempt to introduce the experimental method of reasoning into moral subjects. ... [pt.3]
Hume, David, 1711-1776.

SECT. V. Of the obligation of promises.

THAT the rule of morality, which enjoins the performance of promises, is not natural, will sufficiently appear from Page  102 these two propositions, which I proceed to prove, viz. that a promise wou'd not be in∣telligible, before human conventions had estab∣lish'd it; and that even if it were intelli∣gible, it wou'd not be attended with any moral obligation.

I SAY, first, that a promise is not intelli∣gible naturally, nor antecedent to human con∣ventions; and that a man, unacquainted with society, could never enter into any engagements with another, even tho' they could perceive each other's thoughts by in∣tuition. If promises be natural and intelli∣gible, there must be some act of the mind attending these words, I promise; and on this act of the mind must the obligation de∣pend. Let us, therefore, run over all the faculties of the soul, and see which of them is exerted in our promises.

THE act of the mind, exprest by a pro∣mise, is not a resolution to perform any thing: For that alone never imposes any ob∣ligation. Nor is it a desire of such a per∣formance: For we may bind ourselves with∣out such a desire, or even with an aversion, declar'd and avow'd. Neither is it the will∣ing of that action, which we promise to perform: For a promise always regards some future time, and the will has an influence Page  103 only on present actions. It follows, there∣fore, that since the act of the mind, which enters into a promise, and produces its obli∣gation, is neither the resolving, desiring, nor willing any particular performance, it must necessarily be the willing of that obligation, which arises from the promise. Nor is this only a conclusion of philosophy; but is en∣tirely conformable to our common ways of thinking and of expressing ourselves, when we say that we are bound by our own con∣sent, and that the obligation arises from our mere will and pleasure. The only question, then, is, whether there be not a manifest absurdity in supposing this act of the mind, and such an absurdity as no man cou'd fall into, whose ideas are not confounded, with prejudice and the fallacious use of language.

ALL morality depends upon our senti∣ments; and when any action, or quality of the mind, pleases us after a certain man∣ner, we say it is virtuous; and when the neglect, or non-performance of it, displeases us after a like manner, we say that we lie under an obligation to perform it. A change of the obligation supposes a change of the sentiment; and a creation of a new obliga∣tion supposes some new sentiment to arise. But 'tis certain we can naturally no more Page  104 change our own sentiments, than the mo∣tions of the heavens; nor by a single act of our will, that is, by a promise, render any action agreeable or disagreeable, moral or immoral; which, without that act, wou'd have produc'd contrary impressions, or have been endow'd with different qualities. It wou'd be absurd, therefore, to will any new obligation, that is, any new sentiment of pain or pleasure; nor is it possible, that men cou'd naturally fall into so gross an ab∣surdity. A promise, therefore, is naturally something altogether unintelligible, nor is there any act of the mind belonging to it a.

Page  105 BUT, secondly, if there was any act of the mind belonging to it, it could not na∣turally produce any obligation. This ap∣pears evidently from the foregoing reasoning. A promise creates a new obligation. A new obligation supposes new sentiments to arise. The will never creates new sentiments. There could not naturally, therefore, arise any obligation from a promise, even sup∣posing the mind could fall into the absur∣dity of willing that obligation.

THE same truth may be prov'd still more evidently by that reasoning, which prov'd justice in general to be an artificial virtue. No action can be requir'd of us as our duty, unless there be implanted in human nature some actuating passion or motive, capable of producing the action. This motive cannot be the sense of duty. A sense of duty sup∣poses an antecedent obligation: And where an action is not requir'd by any natural passion, it cannot be requir'd by any natural obligation; since it may be omitted without Page  106 proving any defect or imperfection in the mind and temper, and consequently without any vice. Now 'tis evident we have no motive leading us to the performance of promises, distinct from a sense of duty. If we thought, that promises had no moral obligation, we never shou'd feel any incli∣nation to observe them. This is not the case with the natural virtues. Tho' there was no obligation to relieve the misera∣ble, our humanity wou'd lead us to it; and when we omit that duty, the immorality of the omission arises from its being a proof, that we want the natural sentiments of hu∣manity. A father knows it to be his duty to take care of his children: But he has also a natural inclination to it. And if no human creature had that inclination, no one cou'd lie under any such obligation. But as there is naturally no inclination to observe promises, distinct from a sense of their ob∣ligation; it follows, that fidelity is no natu∣ral virtue, and that promises have no force, antecedent to human conventions.

IF any one dissent from this, he must give a regular proof of these two propo∣sitions, viz. that there is a peculiar act of the mind, annext to promises; and that con∣sequent to this act of the mind, there arises anPage  107inclination to perform, distinct from a sense of duty. I presume, that it is impossible to prove either of these two points; and there∣fore I venture to conclude, that promises are human inventions, founded on the necessities and interests of society.

IN order to discover these necessities and interests, we must consider the same quali∣ties of human nature, which we have al∣ready found to give rise to the preceding laws of society. Men being naturally selfish, or endow'd only with a confin'd generosity, they are not easily induc'd to perform any action for the interest of strangers, except with a view to some reciprocal advantage, which they had no hope of obtaining but by such a performance. Now as it fre∣quently happens, that these mutual per∣formances cannot be finish'd at the same instant, 'tis necessary, that one party be con∣tented to remain in uncertainty, and depend upon the gratitude of the other for a re∣turn of kindness. But so much corruption is there among men, that, generally speak∣ing, this becomes but a slender security; and as the benefactor is here suppos'd to bestow his favours with a view to self-interest, this both takes off from the obligation, and sets an example of selfishness, which is the true Page  108 mother of ingratitude. Were we, therefore, to follow the natural course of our passions and inclinations, we shou'd perform but few actions for the advantage of others, from disinterested views; because we are naturally very limited in our kindness and affection: And we shou'd perform as few of that kind, out of a regard to interest; be∣cause we cannot depend upon their grati∣tude. Here then is the mutual commerce of good offices in a manner lost among man∣kind, and every one reduc'd to his own skill and industry for his well-being and sub∣sistence. The invention of the law of na∣ture, concerning the stability of possession, has already render'd men tolerable to each other; that of the transference of property and possession by consent has begun to render them mutually advantageous: But still these laws of nature, however strictly observ'd, are not sufficient to render them so service∣able to each other, as by nature they are fitted to become. Tho' possession be stable, men may often reap but small advantage from it, while they are possess'd of a greater quantity of any species of goods than they have occasion for, and at the same time suffer by the want of others. The transfer∣ence of property, which is the proper remedy Page  109 for this inconvenience, cannot remedy it en∣tirely; because it can only take place with regard to such objects as are present and in∣dividual, but not to such as are absent or general. One cannot transfer the property of a particular house, twenty leagues distant; because the consent cannot be attended with delivery, which is a requisite circumstance. Neither can one transfer the property of ten bushels of corn, or five hogsheads of wine, by the mere expression and consent; be∣cause these are only general terms, and have no direct relation to any particular heap of corn, or barrels of wine. Besides, the commerce of mankind is not confin'd to the barter of commodities, but may extend to services and actions, which we may ex∣change to our mutual interest and advantage. Your corn is ripe to-day; mine will be so to-morrow. 'Tis profitable for us both, that I shou'd labour with you to-day, and that you shou'd aid me to-morrow. I have no kindness for you, and know you have as little for me. I will not, therefore, take any pains upon your account; and should I labour with you upon my own account, in expectation of a return, I know I shou'd be disappointed, and that I shou'd in vain de∣pend upon your gratitude. Here then I Page  110 leave you to labour alone: You treat me in the same manner. The seasons change; and both of us lose our harvests for want of mutual confidence and security.

ALL this is the effect of the natural and inherent principles and passions of human nature; and as these passions and principles are inalterable, it may be thought, that our conduct, which depends on them, must be so too, and that 'twou'd be in vain, either for moralists or politicians, to tamper with us, or attempt to change the usual course of our actions, with a view to public interest. And indeed, did the success of their designs depend upon their success in correcting the selfishness and ingratitude of men, they wou'd never make any progress, unless aided by omnipotence, which is alone able to new∣mould the human mind, and change its character in such fundamental articles. All they can pretend to, is, to give a new direction to those natural passions, and teach us that we can better satisfy our appetites in an oblique and artificial manner, than by their headlong and impetuous motion. Hence I learn to do a service to another, without bearing him any real kindness; be∣cause I forsee, that he will return my ser∣vice, in expectation of another of the same Page  111 kind, and in order to maintain the same correspondence of good offices with me or with others. And accordingly, after I have serv'd him, and he is in possession of the advantage arising from my action, he is in∣duc'd to perform his part, as foreseeing the consequences of his refusal.

BUT tho' this self-interested commerce of men begins to take place, and to predomi∣nate in society, it does not entirely abolish the more generous and noble intercourse of friendship and good offices. I may still do services to such persons as I love, and am more particularly acquainted with, without any prospect of advantage; and they may make me a return in the same manner, with∣out any view but that of recompensing my past services. In order, therefore, to distinguish those two different sorts of commerce, the interested and the disinterested, there is a cer∣tain form of words invented for the former, by which we bind ourselves to the per∣formance of any action. This form of words constitutes what we call a promise, which is the sanction of the interested com∣merce of mankind. When a man says he promises any thing, he in effect expresses a resolution of performing it; and along with that, by making use of this form of words,Page  112 subjects himself to the penalty of never be∣ing trusted again in case of failure. A reso∣lution is the natural act of the mind, which promises express: But were there no more than a resolution in the case, promises wou'd only declare our former motives, and wou'd not create any new motive or obligation. They are the conventions of men, which create a new motive, when experience has taught us, that human affairs wou'd be con∣ducted much more for mutual advantage, were there certain symbols or signs instituted, by which we might give each other security of our conduct in any particular incident. After these signs are instituted, whoever uses them is immediately bound by his interest to exe∣cute his engagements, and must never ex∣pect to be trusted any more, if he refuse to perform what he promis'd.

NOR is that knowledge, which is requisite to make mankind sensible of this interest in the institution and observance of promises, to be esteem'd superior to the capacity of hu∣man nature, however savage and unculti∣vated. There needs but a very little practice of the world, to make us perceive all these consequences and advantages. The shortest experience of society discovers them to every mortal; and when each individual perceives Page  113 the same sense of interest in all his fellows, he immediately performs his part of any contract, as being assur'd, that they will not be wanting in theirs. All of them, by con∣cert, enter into a scheme of actions, calcu∣lated for common benefit, and agree to be true to their word; nor is there any thing requisite to form this concert or convention, but that every one have a sense of interest in the faithful fulfilling of engagements, and express that sense to other members of the society. This immediately causes that in∣terest to operate upon them; and interest is the first obligation to the performance of promises.

AFTERWARDS a sentiment of morals concurs with interest, and becomes a new obligation upon mankind. This sentiment of morality, in the performance of promises, arises from the same principles as that in the abstinence from the property of others. Public interest, education, and the artifices of politicians, have the same effect in both cases. The difficulties, that occur to us, in supposing a moral obligation to attend promises, we either surmount or elude. For instance; the expression of a resolution is not commonly suppos'd to be obligatory; and we cannot readily conceive how the Page  114 making use of a certain form of words shou'd be able to cause any material differ∣ence. Here, therefore, we feign a new act of the mind, which we call the willing an obligation; and on this we suppose the mo∣rality to depend. But we have prov'd al∣ready, that there is no such act of the mind, and consequently that promises impose no natural obligation.

TO confirm this, we may subjoin some other reflections concerning that will, which is suppos'd to enter into a promise, and to cause its obligation. 'Tis evident, that the will alone is never suppos'd to cause the obli∣gation, but must be express'd by words or signs, in order to impose a type upon any man. The expression being once brought in as subservient to the will, soon becomes the principal part of the promise; nor will a man be less bound by his word, tho' he secretly give a different direction to his in∣tention, and with-hold himself both from a resolution, and from willing an obligation. But tho' the expression makes on most occa∣sions the whole of the promise, yet it does not always so; and one, who shou'd make use of any expression, of which he knows not the meaning, and which he uses without any intention of binding himself, wou'd not Page  115 certainly be bound by it. Nay, tho' he knows its meaning, yet if he uses it in jest only, and with such signs as shew evidently he has no serious intention of binding him∣self, he wou'd not lie under any obligation of performance; but 'tis necessary, that the words be a perfect expression of the will, without any contrary signs. Nay, even this we must not carry so far as to imagine, that one, whom, by our quickness of under∣standing, we conjecture, from certain signs, to have an intention of deceiving us, is not bound by his expression or verbal promise, if we accept of it; but must limit this conclu∣sion to those cases, where the signs are of a different kind from those of deceit. All these contradictions are easily accounted for, if the obligation of promises be merely a human invention for the convenience of society; but will never be explain'd, if it be something real and natural, arising from any action of the mind or body.

I SHALL farther observe, that since every new promise imposes a new obligation of morality on the person who promises, and since this new obligation arises from his will; 'tis one of the most mysterious and incom∣prehensible operations that can possibly be imagin'd, and may even be compar'd to Page  116transubstantiation, or holy ordersa, where a certain form of words, along with a certain intention, changes entirely the nature of an external object, and even of a human crea∣ture. But tho' these mysteries be so far alike, 'tis very remarkable, that they differ widely in other particulars, and that this difference may be regarded as a strong proof of the difference of their origins. As the obligation of promises is an invention for the interest of society, 'tis warp'd into as many different forms as that interest requires, and even runs into direct contradictions, rather than lose sight of its object. But as those other monstrous doctrines are mere priestly inventions, and have no public interest in view, they are less disturb'd in their progress by new obstacles; and it must be own'd, that, after the first absurdity, they follow more directly the current of reason and good sense. Theologians clearly perceiv'd, that the external form of words, being mere sound, require an intention to make them have any efficacy; and that this intention being once consider'd as a requisite circum∣stance, its absence must equally prevent the Page  117 effect, whether avow'd or conceal'd, whether sincere or deceitful. Accordingly they have commonly determin'd, that the intention of the priest makes the sacrament, and that when he secretly withdraws his intention, he is highly criminal in himself; but still de∣stroys the baptism, or communion, or holy orders. The terrible consequences of this doctrine were not able to hinder its taking place; as the inconvenience of a similar doctrine, with regard to promises, have pre∣vented that doctrine from establishing itself. Men are always more concern'd about the present life than the future; and are apt to think the smallest evil, which regards the former, more important than the greatest, which regards the latter.

WE may draw the same conclusion, con∣cerning the origin of promises, from the force, which is suppos'd to invalidate all con∣tracts, and to free us from their obligation. Such a principle is a proof, that promises have no natural obligation, and are mere artificial contrivances for the convenience and advantage of society. If we consider aright of the matter, force is not essentially different from any other motive of hope or fear, which may induce us to engage our word, and lay ourselves under any obliga∣tion. Page  118 A man, dangerously wounded, who promises a competent sum to a surgeon to cure him, wou'd certainly be bound to per∣formance; tho' the case be not so much dif∣ferent from that of one, who promises a sum to a robber, as to produce so great a differ∣ence in our sentiments of morality, if these sentiments were not built entirely on public interest and convenience.