I wish to thank Mary Sirridge, Doug Den Uyl, Doug Rasmussen, David Schmidtz, and Hillel Steiner for their very helpful feedback on portions of this book, George Owers for his excellent editorial suggestions, and Ian Tuttle for his meticulous copy-editing. I also thank Liberty Fund and the Murphy Institute of Political Economy for their generous support.
For Josh and Sara, Rebekah and Jon, and Rose
This book is about the stance within political philosophy known as libertarianism. More specifically, it focuses on the key philosophical themes and arguments that have been offered on behalf of libertarianism. I begin this introduction with an explanation of what political libertarianism is. Then I briefly describe the central themes and arguments of libertarian theory that are developed in this book, and where and in what form these themes and arguments are to be found.
Libertarianism is advocacy of individual liberty as the fundamental political norm. An individual’s liberty is understood as that individual not being subject to interference by other agents in her doing as she sees fit with her own person and legitimate holdings. Your liberty is violated when, by striking you in the nose, I prevent you from using your face as you choose. Your liberty is not violated when I dodge the punch you aim at me which would otherwise rearrange my nose; for my nose is not part of your person or legitimate holdings. Libertarianism — especially in its more hardcore forms — maintains that respect for one’s liberty is the basic moral demand that each individual can make against all other individuals and groups. A bit more precisely, each individual who is not herself violating the principle that liberty is to be respected can demand respect for her liberty from all other individuals and groups. In the name of liberty so understood, each individual who is respectful of others’ liberty may demand that she not be murdered, enslaved, maimed, assaulted, robbed, or subjected to extortion through the threat of being murdered, enslaved, maimed, assaulted, or robbed. So stringent is the demand that individuals not be subjected to such morally criminal treatment that coercion is permissible if (but only if) it blocks or nullifies the effects of such violations of liberty.
Libertarians, as we shall see, differ about the justification of this moral requirement that each person’s liberty be respected. And they may differ about the precise implications of this requirement. However, libertarians are united in the view that violations of the liberty of libertyrespecting individuals are morally criminal whether it is carried out by individual ruffians or by the agents or high officials of political or legal institutions. As John Locke put it in his Second Treatise of Government, «The injury and the crime is equal, whether committed by the wearer of a crown, or some petty villain. The title of the offender, and the number of his followers, make no difference in the offence, unless it be to aggravate it» (1980 : §176). There are no special «reasons of state» that allow a wearer of a crown or a presidential seal or a police badge to treat any individual in ways that would be recognized as criminal homicide, kidnapping, assault, theft, or extortion if carried out by a freelance lout.
Ruling out «reasons of state” means that state action must be vindicated by ordinary norms of morality — the norms by which we judge whether one individual’s treatment of another is morally permissible or impermissible. State actors have no moral privileges. According to the libertarian, at least as a first approximation, ordinary norms of morality require that harmful force or the threat of such force be used against individuals only to defend against or extract restitution for, or to punish initiated force or threat of force, or to enforce compliance with voluntary contracts. Hence, state use of force and the threat of force must also be confined to the functions of defense, restitution, punishment, and the enforcement of contract. Libertarians maintain that the enforcement of a framework within which individuals are secure in their persons, possessions, and contractual arrangements is the key condition for the emergence of a peaceful, tolerant, pluralistic, and prosperous social and economic order. Radical restriction on state action is the key to a flourishing cooperative society.
Hardcore libertarianism rejects all states more extensive than the minimal or night-watchman state which employs coercion solely for the sake of protecting individual liberty. Hardcore anarchist libertarianism rejects even the minimal state on the grounds that in order to be a state it must employ coercion against liberty-respecting individuals. Softer-core versions of libertarianism accept marginal extensions in permissible coercive state action. Such a modest expansion in the scope of acceptable coercive measures may be justified by extending the range of enforceable moral claims that individuals have against their fellows; for example, to claims to assistance when they find themselves in dire straits. Or such an expansion may be based on the view that minor infringements on liberty can be justified if those infringements are necessary to serve some vitally important social condition; for example, the preservation of social peace or maintenance of institutions capable of protecting individuals against major violations of their liberty. As libertarianism becomes softer- core and the small state replaces anarchy or the minimal state as the object of ideological advocacy, libertarianism shades into classical liberalism.
Classical liberals maintain that respect for individual liberty is at least the primary political norm. Moreover, classical liberalism remains united with libertarianism in its insistence that the state and its officials are subject to the same fundamental moral constraints that apply to individuals at large. Classical liberals join libertarians in their willingness to recognize that most of the world historical statesmen of human history have been thieves and murderers writ large. More generally, libertarians and classical liberals are highly suspicious of any proposal to increase the coercive power of the state — and thereby decrease the scope for voluntary action and cooperation — whatever pretext is offered for that aggrandizement. They are united in their threefold opposition to state interference with personal liberty and with economic liberty and all state employment of military force that is not vindicated as strictly necessary for the defense of the liberty of its citizens. 
The overall libertarian (and classical liberal) perspective includes normative commitments concerning the separate moral importance of each individual and the ways in which respect for individual freedom is the appropriate response to the importance and value of each individual, undergirding claims about the nature and bases of cooperative social and economic order, and a myriad of more straightforwardly empirical claims about, for example, the systematic benefits of a regime of private property and voluntary contract; the capacity of free individuals and associations to find non- coercive solutions to many of the problems that they face ;- the capacity of political entrepreneurs to deploy any attractive goal as a device to feather their own nests — often at the expense of those they pretend to serve; and the dangers of state power whether in the hands of dedicated servants of special interests or (worse yet) sincere visionaries. Libertarians conjoin their most basic moral and social theoretic claims with yet more specific empirical and historical contentions about, for example, the beneficial effects of the Industrial Revolution and the expansion of international free trade, the essential role of governmental action in triggering or sustaining various social evils such as racial segregation and economic dislocations, and the generally counter-productive and harmful effects of policies and movements to render people wards of the state. However, these sorts of empirical and historical contentions are beyond the scope of this book, which concentrates on the key philosophical themes and arguments that are supportive of libertarianism.
There are two main philosophical themes that contend for supremacy within libertarian doctrine. There is the natural rights theme, according to which certain deep truths about human beings and their prospective interaction allows us to infer that each person has certain basic (“natural”) moral rights that must be respected by all other persons, groups, and institutions. Respect for these rights is taken to lead predictably to mutually advantageous social and economic order. However, those mutually advantageous outcomes are viewed by champions of the natural rights theme as normative icing on the cake. They are reasons to be pleased about people’s rights being respected; but the fundamental reason for respecting people’s rights is that such respect is morally required by persons’ moral standing as bearers of those rights. In contrast, there is the cooperation to mutual advantage theme, according to which general compliance with certain principles of justice engenders a cooperative social and economic order that is advantageous to all of its members. That mutually advantageous outcome is the societal end — the normative cake itself — that calls upon us to abide by those cooperationinducing principles of justice. Nevertheless, these two approaches are hardly ships that pass in the night. For the restrictions on our conduct that the mutual advantage approach calls upon us to adopt are the same restrictions that the natural rights approach endorses, viz., restrictions against interference with one another’s lives, liberties, and legitimately acquired holdings and contractual claims. 
Still, not all libertarian theorizing gives explicit pride of place to natural rights or cooperation to mutual advantage. Indeed, there is almost no limit to the moral perspectives upon which someone has sought to ground libertarian political conclusions.  A third possible approach that deserves mention is a form of utilitarianism that maintains that the greatest happiness must be pursed indirectly through steadfast compliance with certain constraining moral norms — as it turns out, pretty much the same constraining norms that are celebrated by the natural rights and mutual advantage approaches. Utilitarianism as such asserts that the ultimate standard for assessing a social state is the degree to which the total happiness that obtains in that state exceeds the total unhappiness. Social state S1 ranks higher than social state S2 if and only if aggregate happiness in S1 more exceeds aggregate unhappiness than aggregate happiness exceeds aggregate unhappiness or ill-being in S2. Without further refinement, such a utilitarianism calls for actions and policies that enhance the aggregate happiness even when those actions and policies coercively impose sacrifices on particular, peaceful and nonoffending individuals. The individual is to surrender or be deprived of her life, liberty, or property whenever doing so is truly socially expedient. Conscientious statesmen are always to be alert to opportunities to break a few eggs in order to construct a better social omelet. Such an unrefined, direct utilitarianism is deeply antithetical to the spirit and contentions of libertarianism.
Nevertheless, important utilitarian theorists have maintained that the reasonable form of utilitarianism takes the key to the promotion of overall human happiness to be steadfast reciprocal compliance with norms that are protective of individual liberty — or, more broadly, protective of life, liberty, property, and contract. Such forms of indirect utilitarianism often shade into versions of the mutual advantage perspective because the protection of the liberty of each individual is taken to be essential to the promotion of the greatest aggregate net happiness. For the protection of each individual’s liberty is taken to secure each individual’s opportunity to advance her own good in ways that do not lessen any other individual’s opportunity to promote her own good. A crucial feature of such libertarian-friendly, indirect forms of utilitarianism is that the ultimate «greatest happiness» standard recedes into the background while norms very much like those advocated by natural rights or mutual advantage theorists dominate the moral foreground.
These three philosophical themes are examined and developed in the next three chapters and also in this book’s bonus online chapter. In Chapter 2, “Philosophical Antecedents,” I flesh out these themes historically by providing accounts of John Locke’s natural rights doctrine, David Hume’s account of the principles of justice as the norms that facilitate cooperation to mutual advantage, John Stuart Mill’s contention that the path to the greatest happiness consists in principled respect for individual security and liberty, and Herbert Spencer’s parallel, but broader and more fully libertarian contention that the attainment of the greatest happiness requires replacing the pursuit of expediency with strict regard for the rights that follow from the principle of equal liberty. Chapter 3, “Libertarian Foundations,” and Chapter 4, “Economic Justice and Property Rights,” explore the core claims of the two theorists from the later decades of the twentieth century who are most important for libertarian doctrine, Robert Nozick and F. A. Hayek. Chapter 3 provides an account of Nozick’s articulation and defense of the Lockean natural rights theme in Anarchy, State, and Utopia, Hayek’s Millian indirect utilitarian defense of liberty in his The Constitution of Liberty, and Hayek’s more Humean focus on the justice of the norms that facilitate cooperation to mutual advantage in his Law, Legislation, and Liberty. Chapter 4 provides an account of Nozick’s historical entitlement conception of justice in holdings and his critique of standard doctrines of distributive justice, and Hayek’s critique of “social justice” and his arguments on behalf a free market economic order.
The bonus online chapter, “Further Philosophical Roads to Libertarianism,” — which is available on Polity’s website at http://politybooks.com/mack-online- chapter/ — examines Hillel Steiner’s development and defense of a “leftlibertarian” doctrine that in significant ways follows up on Herbert Spencer’s early Social Statics, Loren Lomasky’s Persons, Rights, and the Moral Community, which offers a Humean-contractarian defense of basic moral rights; Douglas Rasmussen and Douglas Den Uyl’s defense of libertarian political conclusions on the basis of their neo-Aristotelian account of the nature and value of human flourishing; and David Schmidtz’s sophisticated indirect utilitarian libertarian-leaning doctrine. Finally, Chapter 5, “Objections: Internal and External,” begins with the internal debate between anarchist libertarians, libertarians who defend a minimal state that abjures taxation, and libertarians who allow taxation in order to fund rights-protective activities. This chapter then turns to three of the innumerable critiques by opponents of libertarians. I provide accounts and assessments of John Rawls’ critique of Nozickian libertarianism, Liam Murphy and Thomas Nagel’s objection to libertarianism’s characteristic appeal to pre-institutional moral rights, and G. A. Cohen’s efforts to display the attractiveness and feasibility of an egalitarian and (at least in spirit) anti-capitalist economic order.
Throughout this book, I seek to offer critical but sympathetic accounts of central philosophical arguments that are offered in support of libertarian (or near-libertarian) conclusions and to discuss important philosophical criticisms of libertarian theses in ways that further illuminate the libertarian stance. My goal is to advance the reader’s appreciation for these themes within libertarian theorizing. Although I have not been bashful about citing a good number of my own philosophical essays, I have not taken the composition of this book as an occasion for systematically presenting my own best case for libertarian conclusions — including my own views about how directly one may translate one’s theoretical conclusions within political philosophy into reasonable proposals for change in our complex and tangled world.
- The view this book focuses on is often mislabeled, “right-libertarianism.” This label ignores this view’s radical anti- statism, including its rejection of state- enforced moralism and paternalism, coercive state action on behalf of special interests, and state diplomatic and military adventurism.
- These solutions are not limited to standard private property or profitmaximizing institutions. On voluntary mutual aid associations, see Beito (2000). On voluntary communal property arrangements, see Ostrom (1990).
- Some versions of the mutual advantage approach are couched in «contractarian” terminology. For a libertarian version of such an approach, see Narveson (1988: 2017). Other versions of the mutual advantage approach are couched in «public reason” terminology. For a classical liberal-leaning version of such an approach, see Gaus (2012). See also Vallier (2017).
- For example, the individualist anarchist Benjamin Tucker defended a species of libertarianism on the basis of Stirnerite egoism (Tucker 1972), while British idealist Bernard Bosanquet defended a species of libertarianism on the basis of his metaphysical socialism (Bosanquet 2001).