A libertarian theory of justice conceives justice in terms of property rights. It holds that persons are self-owners and have the moral power to acquire property rights in initially unowned external resources. Different variants of libertarianism can be distinguished according to their stance on the famous (or infamous) Lockean proviso. The proviso requires, in John Locke’s words, to leave “enough and as good” for others (Locke 1960 [1689]: §§27, 33, 36) and thus specifies limits on the acquisition of property in external resources. Left libertarians like Hillel Steiner, Peter Vallentyne, and Michael Otsuka provide an egalitarian interpretation of the proviso. Many “right libertarians” reject any kind of proviso.1 Robert Nozick and Eric Mack are prominent exceptions and defend rather weak versions of the proviso. In between, there is room for moderate interpretations of the proviso, and in particular for a sufficientarian interpretation: a “sufficiency proviso.” It is remarkable that this option has rarely been defended.2 The resulting theory of justice can be called moderate libertarianism.
In this article, I make a case for moderate libertarianism, so understood. I argue that moderate libertarianism has advantages over both left and right libertarianism because it better coheres with the most plausible rationale for endorsing a libertarian theory of justice in the first place. The article proceeds in five steps. First, I outline what I take to be the most plausible rationale for a libertarian theory of justice. Second, I argue that this rationale also provides a rationale for a sufficiency proviso, and I elaborate the specifics of that proviso. Third, I try to show that the sufficiency proviso has decisive advantages compared to an egalitarian proviso and—fourth and fifth—compared to the provisos proposed by Nozick and Mack.
It should be noted that I am not going to discuss what John Locke really had in mind with his “enough and as good” proviso. The provisos discussed here can be read as the most plausible interpretations or as new elaborations of Locke’s proviso.
It should also be noted that libertarianism need not be understood as a distinct theory of justice. It can also be conceived as (more or less radical) advocacy of free markets. So understood, libertarianism is compatible with many different theories of justice: One can advocate free markets as the best implementation of Rawlsian justice (Tomasi 2012) or as required by utilitarianism (Epstein 1998), for example. Yet in this article, I understand libertarianism as a distinct theory of justice, one that focuses on property rights. (To live up to its name, a libertarian theory of justice should also draw some close connection between property rights and liberty, but I will not discuss this connection here).
1LIBERTARIAN JUSTICE
Libertarianism is not the only theory of justice that takes private-property rights seriously. But it takes them more seriously than other theories of justice. In John Rawls’s theory of justice, for example, personal private property is granted by his first principle of social justice (1971: 61; 1996 [1993]: 298; 2001: 114), while property rights in the means of production are discussed at a later stage, when the two principles of social justice are institutionalized (1971: 270–4, 280–1; 1996 [1993]: 338; 2001: 135–40, 158–62). Hence, on a Rawlsian view, property rights cannot function as a moral constraint on attempts to realize social justice, because social justice is morally prior to property rights.3 Property rights are themselves merely conceded by principles of social justice or by the institutions that are designed to realize social justice. Of course, once such institutions are implemented, they do grant legitimate, including property, rights (1971: 84, 103; 1996 [1993]: 284; 2001: 50–2, 72). But the institutional basic structure of a society has to be adjusted if it turns out to not adequately realize social justice. One then has to restore “background justice,” and property rights do not have much of a moral standing in that situation (1996 [1993]: 281, 284; 2001: 53–4).
Libertarianism, on the other hand, gives property rights a more prominent place. Because it takes property rights as morally basic, property rights indeed constrain morally legitimate redistribution in the name of social justice. Libertarians have thus been keen to show how theories of social justice are incompatible with property rights and a market order (Nozick 1974: 160–1; Hayek 1998 [1976]: ch. 9; Schmidtz 2010). But libertarians are not opposed to all kinds of redistribution, of course. Redistribution can be required to redress past injustices (although some may not want to call this “redistribution”). What counts as a past injustice depends on the specifics of the libertarian theory of justice. All libertarians believe that redress for violations of self-ownership rights and of property rights in external resources is warranted, of course. The Lockean proviso, depending on its interpretation, can justify further redistribution as some kind of redress or compensation.
What speaks in favor of a libertarian theory of justice? Of course, I cannot develop a fully fleshed-out vindication of a libertarian theory of justice here. But at least I would like to sketch one powerful (type of) argument.4 Persons are purposive beings. They have the capacity to pursue all kinds of projects, including mid- or long-term projects like learning to play an instrument, studying medicine, opening a restaurant, traveling around the world, or founding a family. Trivially, all such projects require the use of one’s body and mind, and so persons should be conceived as self-owners. But almost all such projects of course also require external resources, in one way or another, and they require being able to count on one’s resources. Hence, persons as project pursuers also need the opportunity to acquire private property in external resources (Fressola 1981: 320–1; Lomasky 1987: 120–1; Mack 1990: 532–4; 2010: 60–4; Sanders 2002: 52–3; Tomasi 2012: 76–8; Brennan 2014: 78–82, 92–4; van der Vossen 2015: 77–8).
The argument is obviously a very rough sketch, but I think it is familiar and plausible enough. Note that it does not rely on the moral force of Lockean labor mixing (Locke 1960 [1689]: §§27–30). Rather, private property as a practice is justified as being responsive to persons as project pursuers. The argument leaves open what kind of specific actions should be taken to signify initial appropriation. It vindicates what Eric Mack calls a “practice conception” of private property, not an “inherent-feature conception” (Mack 2010: 54–5; see 1990: 520).
The paradigmatic inherent-feature conception of private property grounds property rights in external resources in labor mixing: The mixing of labor is seen as the inherent feature of an action that confers property rights on the laborer. In Hohfeldian terms (see Hohfeld 2001 [1913, 1917]; Thomson 1990: 37–60; Kramer 1998: 7–60), persons are conceived as having the moral power to acquire external resources via labor mixing. In general, a Hohfeldian power is a second-order capacity to change one’s own or other people’s first-order moral status or, in other contexts, legal status. A Hohfeldian power to acquire property is the capacity to acquire the bundle of Hohfeldian claim rights, liberties, powers, and immunities that defines property rights. This labor-mixing account assumes only one natural right: self-ownership. (A natural right can simply be understood as a non-conventional moral right that all beings with certain properties have). Labor mixing then extends self-ownership rights to external resources, and thus property rights in external resources are grounded in self-ownership.
According to Mack’s practice conception of private property, in contrast, people have at least two natural rights. One is self-ownership; the other is a natural right to the practice of private property or, as he sometimes calls it, a natural right of property. This natural right implies the Hohfeldian moral claim-right “not to be precluded from engaging in the acquisition and discretionary disposition of extrapersonal objects” and the Hohfeldian moral power to appropriate objects in line with the conventions of a justifiable practice of private property (2010: 54). Labor mixing is but one such convention; there are many other ways to let people acquire private property. The natural right to the practice of private property thus allows persons to acquire property rights in external resources that are not grounded in self-ownership (1990: 524–35; 2010: 54–5). Of course, a practice should be suitable for its purpose; not all kinds of acts could plausibly serve as indicators of initial appropriation. Mack argues that a practice of private property is justifiable if it is coherent, comprehensive (allowing appropriation of all kinds of things), transparent, and inclusive (not discriminating against any groups of persons) (1990: 535–7; 2010: 63; see Lomasky 1987: 123; van der Vossen 2009: 363–4).5 In a practice conception of private property, it is not specific appropriative acts that do the moral work of justifying specific property claims but the natural right to the practice of private property. As Bas van der Vossen puts it, a wider theory of private property serves to justify private property, while specific acts of appropriation serve to individuate private property (2009: 362).
One clarification is in order at this point: Some readers may concede that one should endorse the idea of a natural right to the practice of private property (together with natural self-ownership rights) yet deny that this is sufficient to establish a libertarian theory of justice. A libertarian theory of justice, they may say, not only grants everyone these two natural rights but also denies that there are any considerations of justice beyond that. In reply, I would insist that a theory of justice should count as an overall “libertarian” one when it gives considerable weight to self-ownership and the natural right to the practice of private property, even if it combines them with some additional principles of justice. In this article, I will not try to demonstrate that there are no considerations of justice beyond self-ownership and the natural right to the practice of private property. Neither will I try to fully defend the project pursuit rationale for libertarianism. What I aim to show is that if one embraces a libertarian theory of justice due to the project pursuit rationale—that is, if one embraces self-ownership and the natural right to the practice of private property and gives them considerable weight—then one should also embrace a sufficientarian proviso.
2THE SUFFICIENCY PROVISO
In the previous section, I argued that there is a good rationale for endorsing a libertarian theory of justice. In this section, I would like to argue that the same rationale also speaks in favor of incorporating a proviso into that theory.6 In particular, it speaks in favor of incorporating a sufficiency proviso. The rationale for granting persons a Hohfeldian moral power to acquire property in external resources in accordance with conventional practices of private property is that it allows them to securely pursue personal projects. But without actually succeeding in having sufficient resources for pursuing projects beyond mere survival, this power is not of much help. If caring about people as project pursuers is the rationale for advancing a libertarian theory of justice that allows people to acquire property in accordance with conventional practices, it must also require that people indeed have sufficient resources for project pursuit. Without sufficient resources, one simply is unable to live a life as a project pursuer. This is why some sort of sufficientarian proviso should be incorporated into a libertarian theory of justice, requiring that everyone should have sufficient resources for living a life as a project pursuer.7
To put the same point somewhat differently, one could follow G. A. Cohen and distinguish between mere formal self-ownership and “effective” self-ownership. Persons without sufficient resources for project pursuit may formally be self-owners, but they lack effective self-ownership (Cohen 1995: 99–102; see Kymlicka 2002 [1990]: 122–5; Otsuka 2003: 32; Olsaretti 2013; Widerquist 2013: ch. 2). Their property in their bodies and minds lacks any point without sufficient external resources for being able to pursue personal projects. This is why a libertarian theory of justice, with its focus on self-ownership, should also incorporate a natural right to the practice of private property and a sufficientarian proviso.
But how should the sufficientarian proviso be construed, more specifically? In the rest of this section, I develop a more precise conception of the sufficientarian proviso. First of all, the proviso does not apply to specific acts of appropriation but to the practice of private property as a whole. Private property is justified because private property is necessary for project pursuit, but practices of private property should work for all. They should enable everyone to actually live as a project pursuer. Hence, a practice of private property should be designed in a way that makes sure that everyone has sufficient resources to live as a project pursuer. This is the basic idea behind the sufficiency proviso. Of course, the proviso does not say that everyone is to have sufficient resources to succeed in the specific projects he or she actually pursues; these projects may be very expensive or risky, and justice cannot require that everyone succeeds in his or her projects. The proviso merely requires that everyone is to have enough to live as a project pursuer, to be able to pursue projects beyond mere survival. (Survival itself is not to count as a “project”). Thus Jeremy Waldron suggests a proviso that makes entitlements “continually sensitive to the needs of others. […] An adequate Lockean proviso must require that the effect of the [principle of just acquisition] it qualifies is never to require those whom it constrains to choose between compliance and the exigencies of their own survival” (1988: 281). To be able to live as a project pursuer, at least one’s basic human needs have to be met, that is, the needs one shares with all other human beings. These are, quite obviously, needs for food, clothing, shelter, and so on. Some persons, for example, severely disabled or sick persons, may need more resources than others in order to have their basic human needs satisfied. What is needed to be able to live as a project pursuer may also partly depend on the kind of society in which one is living. For example, educational needs will vary from time to time and from place to place.
The sufficiency proviso cannot unconditionally require that everyone be brought above the sufficiency threshold, though. Unfortunately, there are times and places where the economy is too weak to be able to bring everyone above the sufficiency threshold. For that reason, the proviso can only prescribe that the practice of private property should be designed in a way that makes sure that everyone has sufficient resources to live as a project pursuer, if this is possible. But this is still too radical. There are also times and places where it would be possible to bring everyone above the sufficiency threshold but only at a very high price. Bringing everyone above the threshold cannot require undermining the very point of having a practice of private property in the first place. The practice of private property should leave everyone generous space to pursue projects, and this sets limits to what the sufficiency proviso can require. So the proviso can only prescribe that the practice of private property should be designed in a way that makes sure that everyone has sufficient resources to live as a project pursuer, if this is possible without undermining the point of having a practice of private property in the first place. This admittedly does leave quite some room for disagreement about when the point of having a practice of private property is undermined, yet I think this is unavoidable. To ask for more precise boundaries is to ask too much from political philosophy. When the proviso cannot be met without undermining the point of having a practice of private property, then the proviso still applies as a future aspiration and as a goal that a practice should at least try to approximate.
The proviso does not require that everyone has sufficient resources left for initial appropriation (Nozick 1974: 176; Schmidtz 1990: 512; Mack 2002: 247). What counts, from the point of view of the project-pursuit rationale for libertarianism, is not that everyone can initially acquire things but that everyone can come to own and use sufficient things. It does not matter whether someone gets property via free exchange, gift, or initial appropriation or whether he rents or leases things from owners.
The proviso does not ask about the reasons why someone is below the sufficiency threshold. It does not require showing, for example, that someone is below the sufficiency threshold without any fault of his own or because a practice of private property is in place. From the perspective of the project-pursuit rationale for libertarianism, someone not having enough to be a project pursuer is always a concern, no matter what its cause is. Considerations about responsibility are certainly important for designing the institutions that are to implement the proviso, but they do not matter at the level of a theory of justice.
It is most convenient to see the sufficiency proviso as a part of the natural right to the practice of private property (see also van der Vossen 2015: 81–2). The natural right to the practice of private property, recall, includes the Hohfeldian moral power to acquire property rights in external resources in accordance with the conventions of a justifiable practice of private property, and a Hohfeldian moral claim right not to be excluded from such practices. The sufficiency proviso co-determines what a “justifiable” practice of private property is—namely a practice that satisfies the sufficiency proviso. Conceptualized this way, the sufficiency proviso does not assign positive rights or welfare rights to persons.8
But although the proviso does not assign positive rights or welfare rights, persons who benefit from an unjustifiable practice of private property (i.e. from a practice that does not satisfy the sufficiency proviso) have to compensate those who suffered under that practice and had to live below the sufficiency threshold. Those who managed to gain more and better resources than they would have under a justifiable practice of private property that meets the sufficiency proviso can be regarded as “over-appropriators” (Steiner 1994: 268). Yet the main point of the sufficiency proviso is not to vindicate duties of compensation. It is to provide stringent reasons to reform an unjustifiable practice of private property. In that sense, the proviso is both forward looking and backward looking.
Libertarianism as a theory of justice is silent on the institutions that are most appropriate to meet the proviso. It seems natural to think that the proviso speaks for some welfare-state institutions, maybe in the form of a guaranteed basic income, maybe in some other form (Stick 1987: 387–415; Daskal 2010; Friedman 2011: 137–41; Wündisch 2013: 216–9; Zwolinski 2015). But the sufficiency proviso need not vindicate welfare-state institutions. Need-based distribution may not be what persons need (Schmidtz 1997: 9). One could reject welfare-state institutions because one is skeptical about their long-term effectiveness or because one thinks that state institutions are deeply problematic for other reasons, for example because the state’s claims to political authority cannot be vindicated (Huemer 2013; see also Wendt 2015; 2016a). I here stay agnostic on the institutions that best implement the sufficiency proviso.
There are some other difficult issues that I cannot discuss here. One is whether the sufficiency proviso refers to contemporary persons only or whether it also refers to future persons. Another is how practices of private property should be individuated. As practices of private property will usually be partly constituted by laws, it seems plausible to say that we should individuate practices of private property in the same way as we individuate legal systems. But this does not make individuation an easier task, of course. In any case, I assume that one can make a case for the claim that there is not just one worldwide practice of private property.
As the proviso applies to practices of private property and not to individual acts of appropriation, one may ask what it says about appropriations in the absence of a practice of private property. Can a Robinson Crusoe acquire legitimate property titles in his hut, for example? As the sufficiency proviso applies to practices, it certainly does not forbid appropriation in the absence of a practice of private property. But is appropriation even possible in the Robinson Crusoe scenario, on my account? The right to the practice of private property cannot help, since a single person cannot have a practice of private property. Only an inherent-feature conception of private property could justify Robinson’s property rights. I cannot discuss how promising it is to combine an inherent-feature conception and a practice conception of private property.9 But in any case, Robinson’s property titles would be practically irrelevant until other persons show up. Once other persons show up, a justifiable practice of private property is needed, and certainly Robinson’s efforts should count as relevant in specifying property titles within that practice. But the practice also has to satisfy the sufficiency proviso.
I would like to end this section with a brief discussion of an objection to the line of argument I developed so far. I argued that the rationale for endorsing a libertarian theory of justice also is a rationale for endorsing a sufficiency proviso. The objection is that I have misrepresented the rationale for a libertarian theory of justice: Project pursuit should not be taken as a value to be promoted but as a value to be respected. (On this distinction, see Pettit 2002 [1991]: 97.) Because project pursuit is a value to be respected, not promoted, one may not interfere with someone’s project pursuit in order to help someone else to become a project pursuer. But the sufficiency proviso requires exactly this: to interfere with the project pursuit of some in order to help others to become project pursuers. A reply to this objection is that it misunderstands the theoretical place of the project-pursuit rationale. Rights indeed function as “side-constraints,” as Nozick has famously pointed out (1974: 28–9), and thus they are something persons have to respect, not promote. But project pursuit is neither something persons should promote nor respect. It is on a higher theoretical level, justifying and giving shape to people’s rights (that function as side-constraints). To accommodate this point, one could rephrase the objection: The rationale for endorsing a libertarian theory of justice is not to enable everyone to actually live a life as a project pursuer but to formally allow everyone to live a life as a project pursuer. That is why it does not vindicate a sufficiency proviso. The problem with this rephrased objection is that the proposed rationale for libertarianism is hardly convincing. Someone who cares merely about people being formally allowed to live as project pursuers implies that he does not care about the life of poor people who do not have sufficient resources to live as project pursuers. There is nothing very attractive about being formally allowed to live a life as a project pursuer when one is actually unable to live a life as a project pursuer. I conclude that the objection is unconvincing.
3THE SUFFICIENCY PROVISO VS. EGALITARIAN PROVISOS
In the previous section, I argued that the rationale for a libertarian theory of justice also is a rationale to include a sufficiency proviso. I will now spell out the advantages of the sufficiency proviso compared to stronger, egalitarian provisos. A left-libertarian theory of justice claims that every person has self-ownership rights and the Hohfeldian moral power to acquire property rights in external resources, subject to an egalitarian proviso.10 Left libertarians differ in their interpretation of the egalitarian proviso. In Hillel Steiner’s version, persons have a claim right that others do not appropriate more than an equal share of external resources (1994: 235);11 in Michael Otsuka’s and Peter Vallentyne’s version, persons have a claim right that others do not appropriate more than is compatible with equality of opportunity for welfare (Otsuka 2003: 27; Vallentyne 2007: 200). These egalitarian provisos seem to be thought to apply to specific acts of appropriation, but this is not important for our purposes. The same arguments hold if we think of an egalitarian proviso applied to the whole practice of private property, analogous to the sufficiency proviso as introduced in the previous section. So the question is: Why should we prefer a sufficientarian proviso over an egalitarian proviso?
First, the rationale for a libertarian theory of justice does not speak in favor of an egalitarian proviso. In order to be able to securely pursue personal projects, one need not have equal opportunities for welfare or equal resources. One needs to have sufficient opportunities and sufficient resources. The rationale for a libertarian theory of justice that allows the appropriation of private property does speak for a proviso that makes sure that everyone can in fact pursue projects—but not for an egalitarian proviso.
Second, not only does the rationale for a libertarian theory of justice not support an egalitarian proviso. To the contrary, an egalitarian proviso does not cohere well with the rationale for a libertarian theory of justice. It imposes unnecessary harsh restrictions on legitimate project pursuit. As Loren Lomasky puts it, to “insist that persons are morally obliged to bring about equal allocations of material goods is to ignore that each person has primary reason to supply for himself those goods which are needed for the advancement of his own projects” (1987: 122). Otsuka’s proviso is particularly restricting. Under certain conditions, it may not allow some persons to initially appropriate anything, even if there is no scarcity, if an initial appropriation would undermine equality of opportunity for welfare (Arneson 2010: 173–6).12 Otsuka is quite clear about this: He emphasizes that his egalitarian proviso “places no constraints upon the achievement of equality of opportunity for welfare by means of a distribution of worldly resources that leaves the able-bodied with so few resources that they would be forced, on pain of starvation, to come to the assistance of the less talented” (2003: 31). He argues that his proviso nonetheless need not force people to help others on pain of starvation (2003: 32–4), but the problem is that it can. This does not fit well with the idea of giving people space to pursue their projects. Hence, I agree with Richard Arneson when he says that “the spirit (or the underlying rationale) of self-ownership puts constraints on acceptable doctrines of world ownership” (2010: 176).13 The point of a libertarian theory of justice is to give every person generous space to pursue personal projects and hence to have effective self-ownership (see above), and an egalitarian proviso heavily restricts that space. To be sure, a sufficientarian proviso does restrict that space as well. But it does to a much lesser extent, and it is formulated conditionally to make sure that the point of having a practice of private property is not undermined. Moreover, it restricts that space for a reason that coheres with the point of a libertarian theory of justice: to make sure that all persons can live as project pursuers.
4THE SUFFICIENCY PROVISO VS. NOZICK’S PROVISO
I now come to weaker interpretations of the proviso, those advocated by Robert Nozick and—in the next section—Eric Mack. Again, I will argue that the sufficiency proviso has advantages compared to these provisos. According to Nozick’s proviso, every person has a claim right that others do not make her worse off by acquiring external resources (1974: 175–9). The relevant baseline for comparison apparently is the state of nature without the appropriation. Note that an appropriation that once was legitimate can later come to violate the proviso, according to Nozick, when it turns out to have worsened the situation of others. Each owner’s “title to his holding includes the historical shadow of the Lockean proviso on appropriation” (1974: 180). Nozick also applies the proviso to transfers of property: “If the proviso excludes someone’s appropriating all the drinkable water in the world, it also excludes purchasing it all” (1974: 179).14 Moreover, Nozick also applies the proviso to the whole practice of private property. He asks whether “a system allowing appropriation” worsens the situation of persons who are unable to appropriate anything and points at the “various familiar social considerations favoring private property” (1974: 177).
Some commenters think that the proviso should better be applied to specific appropriative acts (and transfers) only (Attas 2003: 359–60; Varden 2012: 427–8), some think that it should better be applied to the system allowing appropriation (Rose 1987; Thomson 1990: 331–2; Wenar 1998: 813–4; Wündisch 2013: 208–16), and some think that Nozick must in any case decide between a proviso applied to specific appropriative acts (and to transfers) and a proviso applied to the system allowing appropriation (Wolff 1991: 112). Without being able to engage the relevant arguments here, I will presuppose that it is possible and coherent to advocate two provisos, one applied to specific acts of appropriation and transfer and one to the whole system that allows initial appropriation. What I would like to do is to show that the sufficiency proviso—which applies to the whole practice of private property—has great advantages over Nozick’s proviso(s).
First, if the rationale for a libertarian theory of justice is to enable persons to live as project pursuers, then Nozick’s proviso is too weak. That one’s situation is not worsened by an appropriation or by the system allowing initial appropriation is simply not enough to grant the necessary external preconditions for living one’s life as a project pursuer. This speaks against Nozick’s proviso and in favor of the sufficiency proviso. A defender of Nozick’s proviso may reply that non-worsening is all a proviso can ask for, because, from a libertarian point of view, no person can be required to better the situation of others. The sufficiency proviso would amount to “forced labor,” the defender may add. Yet the sufficiency proviso does not require any particular person to better the situation of others or to work for others. It is a proviso on practices of private property, saying that a practice should be designed in a way that makes sure that everyone has sufficient resources to be able to live a life as a project pursuer if that is possible without undermining the point of having a practice of private property. If one really cares about everyone being able to live as a project pursuer (and regards this as the rationale to endorse libertarianism), then nothing less than the sufficiency proviso is adequate. Now the defender of Nozick’s proviso may argue that one should not care about everyone being able to live as a project pursuer but about everyone being formally allowed to live as a project pursuer. This brings us back to the objection from the end of section two. There, I argued that the objection fails because the proposed alternative rationale for libertarianism is unconvincing.
Second, an advantage of the sufficiency proviso is that it avoids a common objection to Nozick’s proviso that goes back to G. A. Cohen. That objection says that the relevant baseline for “worsening”—the state of nature without appropriation—is set too low (Cohen 1995: 78–83, 87; Arthur 1987; Stick 1987: 402–7; Kymlicka 2002 [1990]: 117–20; Wolff 1991: 112–3; Christman 1994: 61–2; Wenar 1998: 814–5; Attas 2003: 363–8). Why not compare a specific appropriation to other situations, for example, to the situation where other people make the appropriation or where some sort of group ownership is established? Why not compare the current system allowing appropriation to different systems allowing appropriation, for example those that engage in some redistribution? These questions are pressing for Nozick’s proviso, but not for the sufficiency proviso, because the sufficiency proviso is not comparative and hence does not invoke any baseline at all.
Third, avoiding a state-of-nature baseline is also helpful for another reason. To compare a specific person’s specific current situation with an imagined state of nature seems odd. Eric Mack writes: “The sorts of things available for use in advanced stages of market economies are likely to be quite different from the things that were (or would be) available in some pre-property state of nature. How many microchips equal a hectare of rice paddy? How many cargo containers equal a fishing spear?” (1995: 209; see 2002: 248.) Because the sufficiency proviso does not work with any baseline at all, it is immune to these worries.
Fourth, the sufficiency proviso avoids another objection to any proviso that applies to initial appropriation and leaves a shadow into the future. Preston Werner argues that such a proviso can require a person to give a kidney to compensate for a non-culpable proviso violation, when the proviso’s shadow all of a sudden makes one’s appropriations illegitimate, and when the person has no other means for compensation (2015: 71–2). This does not fit well with libertarians’ strong emphasis on self-ownership as an inviolable or at least highly stringent natural right. While there may well be other ways to respond to this objection—for example, dropping the idea of the shadow or just declaring body parts as immune for claims of compensation—it is an advantage of the sufficiency proviso that it avoids the objection. It avoids the objection because it does not apply to specific acts of initial acquisition, but to the whole system allowing initial appropriation. I have to concede, though, that the whole practice of private property can indeed become illegitimate all of a sudden, when it no longer satisfies the sufficiency proviso. While this primarily constitutes an urgent reason to reform the practice of private property, it may also justify duties of compensation. But this compensation will have to be paid by those who actually gained a great amount of external resources from the unjustifiable practice of private property (“over-appropriators”; see above). Over-appropriators will not have to give away their kidneys to provide the compensation.
5THE SUFFICIENCY PROVISO VS. MACK’S PROVISO
I now come to Eric Mack’s proviso, which he calls the “self-ownership proviso.” Mack starts with the core intuition that someone who owns an island must not let a castaway drown at sea. The owner of the island has to let the castaway get on his island (1995: 187–8; 2002: 246). This intuition cannot be explained with direct reference to property rights, because letting the castaway drown at sea would not be a violation of the castaway’s property rights. Yet the owner of the island would nonetheless act impermissibly, says Mack, because he would severely disable the castaway’s “world-interactive powers.” The self-ownership proviso thus “requires that persons not deploy their legitimate holdings, i.e., their extrapersonal property, in ways that severely, albeit noninvasively, disable any person’s world-interactive powers” (1995: 187). Why should a libertarian theory of justice incorporate the self-ownership proviso? Mack refers to the rationale for granting people self-ownership rights, which is to let them use their world-interactive powers to pursue their own good (or their projects). Self-ownership and the self-ownership proviso have the same rationale (1995: 198–202).
Mack’s proviso is immune to some of the worries regarding Nozick’s proviso. It is immune to the objection that the state-of-nature baseline is set too low. As Mack puts it, the objection misfires because it misunderstands the proper role of a proviso, which is not to limit appropriation but to set limits on the use of one’s property (1995: 216–8; 2002: 100). Mack’s proviso is also not vulnerable to the charge that comparisons with a state-of-nature baseline are odd with regards to specific persons living in advanced societies. No such comparison is needed to show that somebody’s world-interactive powers are severely disabled by some other person. Finally, Mack’s proviso is immune to Werner’s worry that a proviso can require giving a kidney to compensate for a proviso violation, because this worry is based on a proviso conception that applies to initial appropriation and leaves a shadow. As Mack’s self-ownership proviso is no proviso on initial appropriation, the worry does not come up.
So why should one prefer the sufficiency proviso to Mack’s self-ownership proviso? Because the self-ownership proviso is too weak from the perspective of the rationale for a libertarian theory of justice. The first reason for its weakness is that it only applies to the use of people’s property. It does not apply to the whole practice of private property that allows initial appropriation. Mack wants to presuppose that the practice of private property in general is highly enabling for people’s world-interactive powers. He supports, “as a reasonable albeit defeasible presumption, the proposition that the development of liberal private property regimes, by introducing new and expanded forms of receptivity to human powers, are on net enabling of those powers” (1995: 190; see 1995: 212–4; 2002: 249). Only in special cases, where some person or group of persons uses their property in a way that severely disables someone else’s world-interactive powers, does the proviso apply. But this leaves out all cases where someone’s world-interactive powers are severely limited but not due to other persons, or not due to their uses of their property. This is unfortunate if one cares about people actually being able to live their lives as project pursuers. The second reason for the weakness of Mack’s proviso is that persons whose world-interactive powers are not severely disabled can still lack sufficient resources for being able to live their lives as project pursuers. For both reasons, the self-ownership proviso is too weak. The sufficiency proviso better fits the rationale for a libertarian theory of justice.
Interestingly, one could use a different tool from Mack’s theoretical tool box to argue for the sufficiency proviso. This tool is his so-called anti-paralysis postulate. The anti-paralysis postulate determines when and how rights are to be attenuated to permit intrusions of these rights. The anti-paralysis postulate says that we are to specify rights in a way that the very point of having rights is preserved—which is to let individuals pursue their own good (or their projects) (Mack 2011: 112; see my discussion in Wendt 2016a: 102–7). This can justify attenuating rights in order to make room, for example, for self-defense, taxation, or minor forms of pollution. Roughly, then, the self-ownership proviso and the anti-paralysis postulate have opposite tasks: The self-ownership proviso says that some actions are unjust although not intruding on anyone’s rights; the anti-paralysis postulate implies that some actions are not unjust although intruding on someone’s rights. Now Mack does grant, in line with the anti-paralysis postulate, that it is morally permissible for people in dire straits to infringe upon other people’s property rights if necessary to survive, and he tentatively suggests that a social safety net might be appropriate to institutionalize these permissible infringements (2006). But the anti-paralysis postulate could also be used to justify a sufficiency proviso on the practice of private property. To preserve the point of rights, every person needs to have sufficient resources for project pursuit; thus the practice of private property should, if possible, be arranged such that everyone has sufficient resources—and this can mean attenuating rights within the practice of private property.
I should mention two other provisos that apply to the use of one’s property and have been advocated by libertarians. Frank van Dun proposes a free-movement proviso “to the effect that the rights of a property owner do not include the right to deprive others of the possibility of moving between their own property and any place where they are welcome” (2009: 230). Walter Block argues that an owner of a donut-shaped piece of land has to allow others to cross his property to access the land he is blockading (2004: 278). This is sometimes called the “Blockian proviso.” Like Mack’s self-ownership proviso, both the free-movement proviso and the Blockian proviso apply to use, not to initial appropriation. Both are weaker than Mack’s. As I argued that Mack’s self-ownership proviso is too weak already, the free-movement proviso and the Blockian proviso have to be considered too weak as well.
Mack’s self-ownership proviso is too weak. But maybe we should endorse both the sufficiency proviso and Mack’s self-ownership proviso? (And maybe also van Dun’s free movement proviso and the Blockian proviso?) Is it not possible that some person has sufficient resources but still has her world-interactive powers severely disabled by other persons? It is, and so I agree with Mack that there are moral limits on how to use one’s property. I would contend, though, that the self-ownership proviso does not exhaust these moral limits. One should, for example, not severely damage the environment in using one’s property; one should not destroy pieces of great art and important historical monuments, if one should come to own them; and one should not discriminate against people on the basis of sex or race when offering jobs on one’s property. These are just examples. Some of them—perhaps all of them—may not determine enforceable bounds of justice but weaker moral considerations. But they all apply to the use of one’s property. Yet they also apply to cases where no property rights are at stake. One should not severely disable someone’s world-interactive powers or damage the environment by other means than using one’s property. That is why I am inclined to deny that there is a specific proviso on the use of one’s property. There simply are moral considerations beyond a libertarian theory of property rights.15
Frankfurt, H. (1988) “Equality as a Moral Ideal,” in The Importance of What We Care About, Cambridge, UK: Cambridge University Press. (A classic expression of sufficientarianism.)
Lomasky, L. (1987) Persons, Rights, and the Moral Community, Oxford: Oxford University Press. (A form of moderate libertarianism that is different from the one advocated here.)
Mack, E. (1995) “The Self-Ownership Proviso: A New and Improved Lockean Proviso,” Social Philosophy and Policy 12: 186–218. (An elaboration of the “self-ownership proviso”.)
Nozick, R. (1974) Anarchy, State, and Utopia, New York: Basic Books. (Robert Nozick’s discussion of the Lockean proviso can be found on pp. 175–9.)
Otsuka, M. (2003) Libertarianism without Inequality, Oxford: Clarendon Press. (Provides an egalitarian interpretation of the Lockean proviso on pp. 22–9.)
ReferencesArneson, R. J. (2010) “Self-Ownership and World-Ownership: Against Left-Libertarianism,” Social Philosophy and Policy 27: 168–194.
REFERENCE
Arthur, J. (1987) “Resource Acquisition and Harm,” Canadian Journal of Philosophy 17: 337–47.
Attas, D. (2003) “The Negative Principle of Just Appropriation,” Canadian Journal of Philosophy 33: 343–72.
Block, W. (2004) “Libertarianism, Positive Obligations and Property Abandonment: Children’s Rights,” International Journal of Social Economics 31: 275–86.
Brennan, J. (2014) Why Not Capitalism? London: Routledge.
Casal, P. (2007) “Why Sufficiency Is Not Enough,” Ethics 117: 296–326.
Chartier, G., and C. Johnson, eds. (2011) Markets Not Capitalism, New York: Minor Compositions.
Christman, J. (1994) The Myth of Property, Oxford: Oxford University Press.
Cohen, G. A. (1995) Self-Ownership, Freedom, and Equality, Cambridge: Cambridge University Press.
Crisp, R. (2003) “Equality, Priority, and Compassion,” Ethics 113: 745–63.
Daskal, S. (2010) “Libertarianism Left and Right, the Lockean Proviso, and the Reformed Welfare State,” Social Theory and Practice 36: 21–43.
Epstein, R.A. (1998) Principles for a Free Society, New York: Basic Books.
Frankfurt, H. (1988) “Equality as a Moral Ideal,” in The Importance of What We Care About, Cambridge: Cambridge University Press.
Fressola, A. (1981) “Liberty and Property: Reflections on the Right of Appropriation in the State of Nature,” American Philosophical Quarterly 18: 315–22.
Friedman, M. D. (2011) Nozick’s Libertarian Project, London: Continuum.
Hayek, F. A. (1945) “The Use of Knowledge in Society,” American Economic Review 35: 519–530.
Hayek, F. A. (1998 [1976]) The Mirage of Social Justice, in Law, Legislation and Liberty, London: Routledge.
Hohfeld, W. N. (2001 [1913, 1917]) Fundamental Legal Conceptions as Applied in Judicial Reasoning, Burlington, VT: Ashgate.
Huemer, M. (2013) The Problem of Political Authority, London: Palgrave Macmillan.
Kramer, M. (1998) “Rights without Trimmings,” in A Debate over Rights, edited by M. Kramer, N. Simmonds, and H. Steiner, Oxford: Clarendon Press.
Kymlicka, W. (2002 [1990]) Contemporary Political Philosophy, Oxford: Clarendon Press.
Locke, J. (1960 [1689]) “Second Treatise of Government,” in Two Treatises of Government, Cambridge, UK: Cambridge University Press.
Lomasky, L. (1987) Persons, Rights, and the Moral Community, Oxford: Oxford University Press.
Mack, E. (1990) “Self-Ownership and the Right of Property,” Monist 73: 519–543.
Mack, E. (1995) “The Self-Ownership Proviso: A New and Improved Lockean Proviso,” Social Philosophy and Policy 12: 186–218.
Mack, E. (2002) “Self-Ownership, Marxism, and Egalitarianism” (parts I and II), Politics, Philosophy & Economics 1: 75–108 and 237–276.
Mack, E. (2009) “What Is Left in Left-Libertarianism?” in Hillel Steiner and the Anatomy of Justice, edited by S. De Wijze, M. Kramer, and I. Carter, New York: Routledge.
Mack, E. (2010) “The Natural Right of Property,” Social Philosophy and Policy 27: 53–78.
Mack, E. (2011) “Nozickian Arguments for the More-than-Minimal State,” in The Cambridge Companion to Anarchy, State, and Utopia, edited by R. Bader and J. Meadowcroft, Cambridge: Cambridge University Press.
Nagel, T., and L. Murphy. (2002) The Myth of Ownership, Oxford: Oxford University Press.
Nozick, R. (1974) Anarchy, State, and Utopia, New York: Basic Books.
Olsaretti, S. (2013) “Rescuing Justice and Equality from Libertarianism,” Economics and Philosophy 29: 43–63.
Otsuka, M. (2003) Libertarianism without Inequality, Oxford: Clarendon Press.
Pettit, P. (2002 [1991]) “Consequentialism,” in Consequentialism, edited by S. Darwall, Oxford: Blackwell.
Quong, J. (2011) “Left-Libertarianism: Rawlsian Not Luck Egalitarian,” Journal of Political Philosophy 19: 64–89.
Rawls, J. (1971) A Theory of Justice, Cambridge, MA: Harvard University Press.
Rawls, J. (1996 [1993]) Political Liberalism, New York: Columbia University Press.
Rawls, J. (2001) Justice as Fairness: A Restatement, Cambridge, MA: Harvard University Press.
Roark, E. (2012) “Applying Locke’s Proviso to Unappropriated Natural Resources,” Political Studies 60: 687–702.
Rose, C. (1985) “Possession as the Origin of Property,” University of Chicago Law Review 52: 73–88.
Rose, C. (1987) “‘Enough, and as Good’ of What?” Northwestern University Law Review 81: 417–442.
Sanders, J.T. (2002) “Projects and Property,” in Robert Nozick, edited by D. Schmidtz, Cambridge, UK: Cambridge University Press.
Schmidtz, D. (1990) “When Is Original Appropriation Required?” Monist 73: 504–18.
Schmidtz, D. (1994) “The Institution of Property,” Social Philosophy and Policy 11: 42–62.
Schmidtz, D. (1997) “Guarantees,” Social Philosophy and Policy 14: 1–19.
Schmidtz, D. (2010) “Property and Justice,” Social Philosophy and Policy 27: 79–100.
Simmons, A. J. (1992) The Lockean Theory of Rights, Princeton, NJ: Princeton University Press.
Steiner, H. (1994) An Essay on Rights, Oxford: Blackwell.
Stick, J. (1987) “Turning Rawls into Nozick and Back Again,” Northwestern University Law Review 81: 363–416.
Thomson, J. J. (1990) The Realm of Rights, Cambridge, MA: Harvard University Press.
Tomasi, J. (2012) Free Market Fairness, Princeton, NJ: Princeton University Press.
Vallentyne, P. (2007) “Libertarianism and the State,” Social Philosophy and Policy 24: 187–205.
van der Vossen, B. (2009) “What Counts as Original Appropriation?” Politics, Philosophy & Economics 8: 355–373.
van der Vossen (2015) “Imposing Duties and Original Appropriation,” Journal of Political Philosophy 63: 64–85.
van Dun, F. (2009) “Freedom and Property: Where They Conflict,” in Property, Freedom, Society, edited by J. Hülsmann and S. Kinsella, Auburn, AL: Ludwig von Mises Institute.
Varden, H. (2012) “The Lockean Enough-and-as-Good Proviso: An Internal Critique,” Journal of Moral Philosophy 9: 410–442.
Waldron, J. (1988) The Right to Private Property, Oxford: Oxford University Press.
Wenar, L. (1998) “Original Acquisition of Private Property,” Mind 107: 799–819.
Wendt, F. (2015) “Justice and Political Authority in Left-Libertarianism,” Politics, Philosophy & Economics 14: 316–339.
Wendt, F. (2016a) “Political Authority and the Minimal State,” Social Theory and Practice 42: 97–122.
Wendt, F. (2016b) “Four Types of Moderate Libertarianism,” unpublished manuscript.
Werner, P. (2015) “Self-Ownership and Non-Culpable Proviso Violations,” Politics, Philosophy & Economics 14: 67–83.
Widerquist, K. (2013) Independence, Propertylessness, and Basic Income, New York: Palgrave Macmillan.
Wolff, J. (1991) Robert Nozick, Cambridge: Polity Press.
Wündisch, J. (2013) “Nozick’s Proviso: Misunderstood and Misappropriated,” Rationality, Markets and Morals 4: 205–20.
Zwolinski, M. (2015) “Property Rights, Coercion, and the Welfare State: The Libertarian Case for a Basic Income for All,” Independent Review 19: 515–29.
NOTES
1.Most “right libertarians” prefer to be called “libertarians” without any qualification. I discuss their arguments against Lockean provisos in Wendt 2016b.
2.Simmons suggests something like a sufficientarian proviso as an interpretation of Locke’s “enough and as good” proviso (1992: 292–8). For a discussion, see Wendt 2016b.
3.Relatedly, Nagel and Murphy argue that property rights cannot morally constrain taxation (2002: 32–3).
4.Another powerful (type of) argument is consequentialist (e.g. Hayek 1945; Schmidtz 1994). In the end, the project-pursuit rationale and consequentialist arguments may well be interwoven.
5.On the common law practice of private property, see Rose 1985.
6.Mack pursues a similar strategy (1995: 198–202). See also van der Vossen 2009: 365–7.
7.On non-libertarian sufficientarianism see, e.g., Frankfurt 1988; Crisp 2003; Casal 2007. I discuss the idea of combining a proviso-free libertarianism with an independent sufficiency principle in Wendt 2016b.
8.For a libertarian theory of justice that endorses moderate welfare rights see Lomasky 1987: 125–9, 96–7. I discuss his theory in Wendt 2016b.
9.Mack, although advocating a practice conception, also endorses some inherent-feature conception (1990: 528).
10.“Left libertarianism” is used in a different sense in Chartier and Johnson 2011.
11.More precisely, every person originally owns an equal share of external resources and in that sense, the earth is not initially unowned, but no specific bundle of external resources is ascribed to specific persons and so there is a place for something like initial appropriation (Steiner 1994: 235n11).
12.In that sense, an egalitarian proviso will regularly clash with “effective” self-ownership (Cohen 1995: 102–5; Quong 2011: 66–77).
13.For an argument that Steiner’s views on ownership in external resources also undermine self-ownership, see Mack 2009: 116–26.
14.Roark argues that any proviso on initial appropriation has to be applied to the use of unappropriated resources as well (2012).
15.I presented earlier versions of this paper at a conference of the Association for Social and Political Philosophy in Amsterdam in June 2015, at a MANCEPT workshop on “Lockean libertarianism” in Manchester in September 2015, at a paper workshop at Bielefeld University in February 2016, and in a submitted symposium session at the Central Division Meeting of the American Philosophical Association (APA) in Chicago in March 2016. I thank all audiences for invaluable feedback, I thank Bas van der Vossen for his excellent commentary at the APA in Chicago, and I thank the three editors for their very helpful written comments.