by Scott Soames
All of this should sound familiar to Americans. It is impossible to read the founding documents of the United States, and the arguments of those supporting them, without hearing echoes of Locke. As one influential commentator has noted,
[T]here can be no doubt of his great influence on America.… In fine, the widespread and lasting effects of Locke’s Treatise of Civil Government is a standing disproof of the notion that philosophers are ineffectual.6
David Hume, the great empiricist philosopher who was also a leading historian of England, added social, historical, and biological dimensions to Locke’s conception of limited government. Hume’s contributions began with his moral philosophy, the key to which fits his epistemology, discussed in the previous chapter. According to Hume, reason is capable of providing absolutely certain knowledge of necessary, a priori truths, but this is only because those truths are merely “relations of ideas,” which, in themselves, tell us nothing about the world. Establishing any significant matter of fact involves not only reason but also observation. Action adds another dimension. Although reason and knowledge of the world allow us to calculate the means to our ends, they cannot provide those ends. Since action requires the motivating force of desire, Hume took it to be axiomatic that no statement that can be established by reason and observation alone is sufficient to fully guide or explain action. For that we need to include the values sought by the actor, which, in his words, were supplied by the passions.
Lessons for morality were close at hand. Since moral rules are intended to guide action, the passions, which motivate action, must be the source of morality. Since moral action requires moral ends, the values inherent in our nature must not be entirely self-centered, but rather must include other-regarding values that relate us to our fellows. To act morally, we must desire the well-being of others, especially, but not exclusively, the near and dear. For Hume, it was simply a psychobiological fact that we are prone to be benevolent and to approve of character traits, dubbed “natural sentiments,” like honesty, industry, integrity, courage, loyalty, and kindness, while disapproving of their opposites. As he put it, “Morality is more properly felt than judged of.”7
Hume’s political philosophy adds a new element. Whereas his anti-rationalist ethics is anchored in natural sentiment, his anti-rationalist political philosophy is anchored in historically evolving institutions. Society, as he sees it, arises from our needs, from the scarcity of resources available to satisfy them, and from the absence, in the state of nature, of a system of property and division of labor to make productive use of those resources. Think of it this way. Rationality tells me I will benefit from cooperation with others, if they will cooperate with me. Past experience adds that they will cooperate with me only if I do my part. Because we all realize this, we tacitly agree on common rules to be obeyed by all, which will, in the end, benefit everyone. I learn to keep my word, to do what I have promised, to respect your property, and not to interfere with your enjoyment of what you have earned; you learn the same. Continued interaction generates a social convention that, in Hume’s words,
is entered into by all members of society to bestow stability on the possession of … external goods, and to leave everyone in the peaceable enjoyment of what he may acquire by his fortune and industry.… I observe that it will be in my interest to leave another in possession of his goods, provided he will act in the same manner with regard to me.8
Hume regards the needed moral framework to be neither an explicit contract nor a hypothetical construct, but rather a social convention arising from historically evolving institutions that progress by trial and error.
Nor is the rule concerning the stability of possession the less derived from human conventions, that it arises gradually, and acquires force by a slow progression, and by our repeated experience of the inconveniences of transgressing it. On the contrary, this experience assures us still more, that the sense of interest has become common to all our fellows, and gives us a confidence of future regularity.… In like manner are languages gradually established by human conventions without any promise [explicit agreement or contract]. In like manner do gold and silver become the common measures of exchange.9
In short, human societies are governed by moral rules that are social conventions that work. In this way, he arrives at rules governing property, its voluntary transfer, and the enforcement of promises.10 Taking them to be scientific regularities found in political and economic institutions in communities of a certain size, he calls the rules “Laws of Nature.”11
It may seem puzzling, given his distinction between fact and value, that Hume calls these principles of social and political morality laws of nature. According to him, no statement of value—of what should be, or of what one ought to do—follows logically from any factual statements. As he would put it, one can’t derive an ought from an is. One can agree to any factual claims while disputing any moral claims without being guilty of logical inconsistency. How then can Hume call the social conventions governing property, promises, and other moral matters “Laws of Nature”? Surely, laws of nature, like Newton’s laws, are facts. So, it would seem, Hume must think that the social conventions that make up morality are social facts.
He does, in fact. Nevertheless, he also takes these “laws” to be normative—i.e., to be rules we should follow. He says that justice—or fairness—is generally approved, and so is a virtue, because it is known to be in everyone’s interest. He notices that this approval is freely granted, despite our awareness free riders—i.e., of people who pretend to cooperate but in fact don’t. These people know that the general obedience to accepted social rules is in everyone’s interest, including their own. Still, they secretly opt out and fail to do their part when they can get away with it. Hume thinks they ought not.12
Why do we recognize such narrowly self-interested behavior to be wrong? Hume hints at the answer when considering our reaction to injustice done to others but not ourselves. He says such action
still displeases us; because we consider it as prejudicial to human society, and pernicious to every one that approaches the person guilty of it. We partake of their uneasiness by sympathy … this is the reason why the sense of moral good and evil follows upon justice and injustice. And though this sense, in the present case, be derived only from contemplating the actions of others, yet we fail not to extend it even to our own actions [i.e., we come to think that we ought not to act in that way].… Thus self-interest is the original motive to the establishment of justice: but a sympathy with public interest is the source of the moral approbation which attends that virtue.13
Hume takes free-riding—reaping the benefits of social cooperation while not doing one’s part—to be immoral because it violates the social conventions that secure other-regarding values inherent in our human nature, and so common to us all.
From today’s perspective, it is natural to think of these values as arising from our biological nature plus the commonalities of human culture derived from thousands of years of living in communities. The competitive advantages of social cooperation are so great that the degree to which various groups of our human and nonhuman ancestors mastered the dynamics of cooperation must have had important effects on which groups survived and which didn’t. Survival of the fittest suggests that we carry the traits of the winners. Biologically we emerged as highly social animals who not only depend on, but also care about, others in our social group. In this way, unrenounceable other-regarding values became inherent to our nature. Because they are part of our biological makeup, these values provided the raw material for gradually evolving institutions of social cooperation that have become moral fixed points in most human societies.
These claims are both factual and normative. They are factual claims about the values arising in normal human beings from their biological inheritance, childhood experience, and the cultural institutions they are born into. They are normative principles because the values described are not erasable from our nature. The factual
claims have normative power because the values they describe are ours, the ones we want to live by. Hume grouped them together under the headings self-interest, justice, and sympathy.
Imagine a species of rational creatures who didn’t have social values—each of whom cared only for him or herself, and placed no value on the well-being of others. They might be as intelligent and rational as we are, but without any desire to form social attachments. They might cooperate when they believe it to be to their own individual advantage, but they would always be on the lookout for ways to cheat the system, and bend it to their own selfish interests. Hence, they wouldn’t trust one another and they would have no socially inculcated morality. Being without Hume’s natural sentiment, their systems of cooperation would be much more fragile and limited than ours. Because of this, their chances of evolutionary success might not be very great. Fortunately, they are not us.
Another aspect of Hume’s social and political philosophy lies in its rejection of rationalistic schemes of social organization, its concern for liberty and innovation, and its focus on naturally arising institutions, participation in which wins general approval by proving to be in most people’s long-term interest. Here Hume the historian of England meets Hume the philosophical critic of those who place too much faith in the power of reason. Unlike Rousseau, whose abstract conception of the general will encouraged authoritarianism, Hume’s empiricism encouraged liberty. Thus, it’s not surprising that, like Locke, he influenced the founders of the United States—as illustrated by James Madison’s use, in Federalist Paper 10, of Hume’s argument against Montesquieu to show how and why a representative republic governing a large and diverse society could safeguard liberty by combatting the dangers of faction.14
Hume was only one of several Scottish philosophers who influenced early America. Another Scotsman, though not a major philosopher himself, was the philosophically minded clergyman John Witherspoon (1723–1794). Witherspoon was president of Princeton from 1768 to 1794, where he was also head of its Philosophy, History, and English departments. A devotee of the school of commonsense realism of the Scottish philosopher Thomas Reid (1710–1796), Witherspoon may have done more than anyone else to spread the influence of the Scottish Philosophical Enlightenment in the new world. After his arrival in America, he became a staunch advocate of independence, and an important intellectual influence during and after the Revolution. A member of the Continental Congress and signer of the Declaration of Independence, he was the teacher of future president James Madison, and of four other representatives at the Constitutional Convention in 1787 as well. He also taught Aaron Burr, who became vice president of the United States, as well as three future Supreme Court justices, 28 future United States senators, and 49 former students who became members of the House of Representatives.
Another Scottish philosopher who influenced both Hume and Witherspoon was Francis Hutcheson (1694–1745). Hutcheson, who held the Chair in Moral Philosophy at the University of Glasgow from 1729 to until his death, was, like Hume, a moral-sense theorist who argued against Hobbes that human nature included social and benevolent elements. These theories of Hutcheson and Hume had a strong influence on Hutcheson’s most famous student, Adam Smith (1723–1790). Smith studied philosophy first at Glasgow and later at Oxford, after which he lectured at Edinburgh, where he met Hume, who become his dear friend and philosophical mentor. As Arthur Herman notes:
As a philosopher and as a friend, Hume made a huge impact on Adam Smith. Smith read and understood him more thoroughly, perhaps, than any other contemporary. His own writings would be inconceivable without Hume’s peculiar take on the “progress” of civil society, and on what an imperfect, trial-and-error process it truly is.15
In 1751 Smith was appointed professor of logic at Glasgow. In 1752, he was awarded the Chair of Moral Philosophy, which had been occupied for 16 years by Hutcheson. Smith himself occupied the chair for twelve years, teaching logic, moral philosophy, economics, and jurisprudence. His 1759 book The Theory of the Moral Sentiments—regarded by Smith at the end of his life as his best work—was a philosophical treatise on morality based on a theory of human nature along the lines of Hutcheson and Hume. But the book the world came to recognize as his masterpiece was The Wealth of Nations, published in 1776. The founding document of classical economics, it explained how individuals pursuing their own economic self-interest under conditions of fair and honest competition will, as if led by “an invisible hand,” increase not only their own prosperity, but the prosperity of society as a whole. In the book, Smith emphasizes the efficiency and wealth-producing potential of free trade, free markets, and the division of labor, while warning against monopoly, unfair restraint of trade, and government protectionism of favored businesses. He also measured the wealth of a society not by its reserves of gold and silver, but by the value of all goods and services it produces.
The influence of The Wealth of Nations has, of course, been profound. But it wasn’t anomalous. Taken together, the moral, political, legal, and social philosophy of seventeenth- and eighteenth-century philosophers from Hobbes and Locke to Hume and Smith gave us the theoretical foundations of limited government and modern economies, leading, as Smith seemed to foresee, to the greatest expansion of liberty and prosperity the world has ever known. Writing his masterpiece in the autumn of 1775, he says this about the society likely to result from the coming American Revolution:
They are very weak who flatter themselves that … our colonies will be easily conquered by force alone. The persons who now govern the resolutions of what they call the Continental Congress feel in themselves at this moment a degree of importance which, perhaps, the greatest subjects in Europe scarcely feel. From shopkeepers, tradesmen, and attorneys, they are become statesmen and legislators, and are employed in contriving a new form of government for an extensive empire, which … seems very likely to become one of the greatest and most formidable that ever was in the world.16
Overall, the record of seventeenth- and eighteenth-century philosophical accomplishment in the social, political, and moral sphere is similar to that era’s record of achievement in physics, mathematics, and natural philosophy. In the previous chapter we saw that Isaac Newton, the foremost physicist of his era, read philosophy and displayed a remarkably philosophical turn of mind in his thoroughly scientific work. The relation of Adam Smith, the first modern economist, to philosophy was even closer. In addition to studying Hobbes, Hume, and Hutcheson, Smith taught philosophy, he wrote some of the most important moral philosophy of his day, and he correctly took himself to be a philosopher.
There was, during this period, no sharp contrast between the multiple roles played by leading thinkers. As Newton, Boyle, Descartes, and Leibniz illustrated, there was no fundamental discontinuity between making contributions to physics and mathematics and making contributions to metaphysics and epistemology; nor, as Hume and Smith illustrated, was there a fundamental discontinuity between making contributions to history and economics, and making contributions to moral, political, or social philosophy. The world-transforming advances of the seventeenth and eighteenth centuries in politics, economics, and social organization could not have occurred without the philosophers of this era.
Philosophers were also responsible for a similar transformation in naturalizing moral thought, grounding it in human nature, rather than in natural or revealed theology. As we have seen, one of these approaches, championed by Hume, Hutcheson, and Smith, grounded it in our moral, other-regarding sentiments. The other major approach was championed by one of the philosophical giants of all time, Immanuel Kant. His most striking contribution to morality, the categorical imperative, identified our common rationality—not our benevolent sentiments (which Kant would have regarded as too variable and insecure)—as the source of morality. Anyone who asks “What if everybody did that?” in contemplating the permissibility or impermissibility of an act, is echoing Kant’s imperative, which directs one to act only on rules that one can rationally will
to be universally followed, or perhaps be universally accepted. Kant illustrated his idea with two paradigmatic examples. According to him, lying and promise-breaking are impermissible because they are, in a certain way, rationally inconsistent. If everyone routinely lied or broke promises, the social conventions of truth-telling and promise-fulfilling would not exist, thereby destroying the reservoir of trust that makes lying and promising possible. Since universal lying or promise-breaking is, therefore, conceptually impossible, no rational being can will, or intend, such behavior to be a universal law. Thus, Kant argues, it is never morally permissible to lie or break a promise.
Although this was a good thought, it was too extreme. There are occasions when it is permissible, and even morally required, to lie or break a promise. There are also things that everyone could do—acts that could, without contradiction, be willed to be done universally (e.g., rehearse secret fantasies of revenge every day)—that one shouldn’t do. However, these defects in the strictly Kantian formulation might be addressed by more nuanced versions of the view. For example, one might hold (roughly) that an act is morally impermissible if it is prohibited by rules the universal adoption of which as social conventions would produce the best system of social cooperation between free and equal parties; an act is morally required if it is mandated by rules the universal adoption of which as social conventions is a necessary feature of any effective system of social cooperation between free and equal parties; and all other actions are morally permissible.
This view is Kantian in calling for the universal adoption of moral rules. But it is also consequentialist in assessing moral rules by the value of the consequences of adopting them, and also in taking the rules to be social conventions observed in normal cases, while allowing deviations in exceptional cases when justified by the need to avoid overwhelmingly bad consequences, or the opportunity to achieve overwhelmingly good ones. Such a rough-and-ready code would tell us, among other things, (i) that lying, promise-breaking, harming or coercing others, infringing on their natural liberty, or violating their rights to property are justified only in extreme or unusual cases, and (ii) that, except in such cases, one is required to support oneself (if possible), to provide for one’s children, to contribute to needed public services, and to donate a portion of one’s income, above a certain minimum, to care for those who are unable to care for themselves. Many difficult cases would, of course, remain to be adjudicated. But this doesn’t detract from the usefulness of this amalgam of the moral and social philosophies of Hume and Kant.17
