Animals and the Limits of Justice*

Paola Cavalieri


In the third century AD the Neo-Platonic philosopher Porphyry offered with his De abstinentia an impressive case for a radical change in the ethical treatment of nonhumans. In summarizing past debates and rebutting rationalizations for animal exploitation, Porphyry dealt with many traditional philosophical objections. Among them, one is particularly ambitious. Attributed by Porphyry to the Stoics, it is usually referred to as the Stoic objection concerning justice. The objection maintains that justice is destroyed - “confounded” - by any endeavour to extend it to nonhumans, since, for those who make such an attempt, no road of justice is left, “either broad or narrow”.  I shall first consider the use of the notion of justice in this context. Then, I shall challenge the allegation in its own merits, connecting its elements with somewhat parallel contemporary arguments. Finally, I shall reverse its claim. In other words, what I shall argue is that justice is destroyed by its being confined to human beings.


The Text

Porphyry’s summary of the Stoic objection is very dense:

Our opponents therefore say, in the first place, that justice will be confounded, and things immoveable be moved, if we extend what is just, not only to the rational, but also to the irrational nature; conceiving that not only Gods and men pertain to us, but that there is likewise an alliance between us and brutes, who [in reality] have no conjunction with us....

For he who uses these as if they were men, sparing and not injuring them, thus endeavoring to adapt to justice that which it cannot bear, both destroys its power, and corrupts that which is appropriate, by the introduction of what is foreign. For it necessarily follows, either that we act unjustly by [not] sparing them, or if we spare, and do not employ them, that it will be impossible for us to live. We shall also, after a manner, live the life of brutes, if we reject the use of which they are capable of affording.... For it would be impossible to assign any work, any medicine, or any remedy for the want which is destructive of life, or that we can act justly, unless we preserve the ancient law illustrated by Hesiod, a law by which, distinguishing the natural kinds and giving each class its special domain,

“To fishes, savage beasts, and birds, devoid
Of justice, Jove to devour each other
Granted; but justice to mankind he gave.”

i.e., toward each other.

But it is not possible for us to act unjustly towards those who cannot be just towards us. Hence, for those who reject this reasoning, no other road of justice is left, either broad or narrow, into which they can enter. For, as we have already observed, our nature, not being sufficient to itself, but indigent of many things, would be entirely destroyed, and enclosed in a life involved in difficulties, inorganic, and deprived of necessaries, if excluded from the assistance derived from animals.1



What exactly is one referring to when one discusses justice and animals? In a recent discussion of the question, 2 Martha Nussbaum states that, under the capabilities approach she favors - an approach stressing that individuals have the basic right to be “all that they can be” with the support of internal and external conditions - nonhumans, as conscious and purposive agents, do have entitlements based upon justice. However, speaking of animals who are under human control, she does not advocate their enfranchisement, but merely laws banning cruel treatment. She also suggests that research that inflicts pain and premature death on nonhumans, thus violating their basic entitlements, should continue if it is really necessary for a major human capability. Thus, what Nussbaum refers to seems to be a quite limited form of protection - nothing more than some restraint to be imposed on our exploitive behavior. It seems that what we face here is a typically post-Cartesian perspective, characterized by a focus on animal suffering and a disregard for animal lives.3 Can this really be called justice?

In Greek mythology, justice, or Dike, is a powerful character.4 At the dawn of Western philosophical reflection, the goddess is still present as a metaphor for the abstract notion of justice, and a proof of her power is offered by the way Parmenides defines her - Dike the Equalizer.5 Though much of this halo goes lost in subsequent philosophers, justice remains one of the most eminent among our ethical notions. Indeed, Aristotle states in the Nichomachean Ethics that justice, insofar as it is displayed towards others, is often thought to be the “chief of the virtues”. 6 And it is to Aristotle that we owe the most pervasive philosophical framing of the question of justice and its place in ethical and political discourse. In the Politics, Aristotle on the one hand suggests that justice is defined to be equality in relation to individuals, and on the other raises the question, In what does such equality consist? Thus, he first offers us a formal principle, which tells us that relevantly similar cases are to be treated alike. Such formal principle is first and foremost a principle of rationality - since reasons are general, when two situations are relevantly alike, the reasons that apply are the same -  and becomes an ethical principle when it is applied to the treatment of individuals. Second, in relation to such principle, he points to a problem that is not formal but substantive: what are the relevant similarities and dissimilarities, and why are they relevant? 7 In spite of impressive changes in the substantive interpretation of the underlying idea of equality, Aristotle’s formal principle can be seen as an enduring aspect of philosophical discussions about justice.8 The formal aspect of justice will in fact remain quite uncontroversial in ethical and political reflection. It will reach Thomas Aquinas, 9 and will be later embodied by authors as distant as Hume and Kant, as well as in the different strands of thought they generated. 10

If, in the light of this brief survey, we go back to Nussbaum’s views, it is plausible to ask: how does she specify, and justify, both the relevant conception of equality and the attendant relevant differences between humans and nonhumans which authorize her to reduce justice to such a small thing when applied to the latter group? The answer is disappointing. Apparently, Nussbaum does not even deal with the question - she merely assumes that there are relevant differences, and that they are so weighty as to sanction a weighty difference in treatment. In obvious contrast with this, what the Stoics consider as the extension of justice to nonhumans is captured by the idea of treating them as if they were human beings - “For he who uses these as if they were men...” -  something that directly points to the formal approach to justice as equality in treatment. Moreover, such extension revolves around the possibility of “sparing and not injuring them” - that is, not exploiting them for food or work - something that specifies the normative requirement of banning their institutional use as mere means. In other words, what is at stake is the inclusion of nonhumans in the human community and covenants.

It is thus to this use of the notion of justice in its full force that I shall refer when I shall challenge the Stoic objection in its own merits. Formally, by extension of justice to nonhumans I shall mean just the extension of a like treatment with human beings. And, normatively, since what is in question is basic treatment - institutional protection from exploitation - I shall set aside specific philosophical interpretations in order to focus on fundamental moral equality as specified by the universally accepted doctrine of human rights.

According to the best justification of such doctrine, the requisite that entitles to equal human rights is that of being an agent - an intentional being having goals and wanting to pursue them. It is common belief that (many) members of species other than our own are agents - as we have seen, Nussbaum herself concedes this. Thus, I shall number (many) nonhumans among the candidates for admission into the sphere of equal justice, and I shall then consider if the Stoics’ alleged grounds for their exclusion meet the standards of relevance embodied in the contemporary egalitarian paradigm. If such grounds turn out to be irrelevant, then (many) nonhumans will be shown to be like cases with humans, deserving like basic treatment.



Having so clarified our general framework, we can directly turn to the Stoics’ allegation. It is apparent that the objection, which, as presented, is somewhat confused, is dominated by the scheme of the reductio ad absurdum - that is, by that type of logical argument where one assumes a claim, arrives at an absurd result, and then concludes that the original assumption was wrong, since it gave an absurd result. Accordingly, it is to specific versions of such argument that our classification will make reference. We shall lump all the arguments around three headings: metaphysical absurdity, practical absurdity, and ethical absurdity.


Metaphysical Absurdity

Perhaps the most striking among the Stoic statements is the claim that, if we extend justice not only to rational, but also to irrational beings, “things immoveable be moved”. To what exactly are the Stoics referring? Our mistake in extending justice to the other animals would lie, it is claimed, in “conceiving that not only Gods and men pertain to us, but that there is likewise an alliance between us and brutes, who... have no conjunction with us”. The notion of “connection”, or affinity - oikeiosis - which is central to Stoic ethics, refers to an innate care for one’s own self which, though present in all animals, in humans is allegedly programmed by the natural order to reach beyond themselves to their family and group, and then, more dilutedly, to the entire human race - but to no nonhuman beings.11 The Latin author Cicero thus summarizes the Stoics’ view: “Just as [they] think that the bonds of justice unite men with each other, so too they deny that there is any bond of justice between man and beast. [They] expressed it well, saying that everything else was born for the sake of men and gods, but they were born for the sake of their own community and society”.12 Accordingly, the absurdity involved would consist in contradicting a twofold belief about the way the world is arranged - the belief that a) there is a natural connection between humans and Gods, while b) there is no similar connection between humans and nonhumans.

It is not necessary to point to the mention of “Gods” to stress that the reference framework of the allegation is a specific interpretation of the universe. It is not uncommon - indeed, it is the rule - for pre-modern, non-autonomous ethics to directly borrow normative stances from descriptive premises. In fact, the contemporary philosophical descriptive/prescriptive contrast is out of place here. For, first, such worldviews integrate empirical description with particular metaphysical construals. And, second, they assume the perspective that Being, or the ultimate reality, already embodies values which the “good” human life should assume. Returning to our point, one among the Stoics’ main ethical tenets is that the good human life resides in “following nature,” and that, as we have seen, implies the withholding of affinity from nonhuman beings.13

What, then, should we make of the Stoic interpretation of nature’s intentions regarding Gods, humans and nonhumans, and of the connected idea that such intentions carry for us normative implications? As for the former aspect, an obvious problem arises. While we know how to justify or correct our beliefs on physical objects, we have no idea regarding how to justify or correct our metaphysical beliefs on the ultimate nature of things. Due to its metaphysical component, thus, the Stoic denial of a connection between “us and brutes” turns out to be the fruit of an unverifiable stance which cannot aspire to universal acceptance, and should therefore be excluded just as we exclude any idiosyncratic metaphysical views from human rights theory. Incidentally, moreover, it should be noted that what contemporary science tells us is just the contrary. For today’s scientific paradigm informs us that, if there is a clear and demostrable connection, this is the one between humans and animals - indeed, between human and nonhuman animals.

If, on the other hand, we turn to the latter element - that is, to the injunction to respect such an alleged order of nature by not intermingling with animals - the obvious rejoinder is that such injunction violates Hume’s law, insofar as it directly derives an ought from an is.14 In other words, even in case the interpretation of the nature of things to which the Stoics point had the support of scientific enquiries rather than of metaphysical speculations, we could not directly derive from it either the specific Stoic injunction or any other injunctions whatsoever. To better understand this point, consider an analogous derivation of a matter of value from a matter of fact. In the scientific field of sociobiology, some authors have argued for the “naturalness” of male dominance within the human species. Following the lines of the Stoic argument, in case we reached the conclusion that this disturbing aspect of our social life is indeed for us a natural biological inclination, we should not only desist from morally blaming it, but should also stop endeavouring to minimize it.15

In the light of this, it seems we can reject the metaphysical reductio. Before concluding, however, a further point is worth emphasizing. One key element of the contemporary discussion of the ethical treatment of nonhumans is the challenge to the discrimination against animals on the grounds of their biological membership. For it often happens that, both at the lay and at the philosophical level, it is claimed that we are entitled to withhold justice from animals simply because they “are not human” - something that, in today’s discussion, amounts to saying that they don’t posses a genotype characteristic of the species Homo sapiens. The challenge to this form of discrimination is quite straightforward: if we maintain, as we do, that biological characteristics such as race or sex membership cannot in themselves carry any direct ethical weight - that racism and sexism are unacceptable - then we cannot grant direct ethical weight to another biological characteristic such as species membership - speciesism too is unacceptable.16 In the face of such  a challenge, it is difficult to understand how speciesism can be defended at all. If, however, rather than confining our attention to the contemporary biologic outlook on species differences, we broaden our attention to the traditional metaphysical approaches of which the Stoic doctrine is an example, and which include essentialist views of human and animal “nature” implying differences in kind often charged with sacral significance, we can shed some light on the persistence of such an implausible way of drawing the moral line between human and nonhuman beings.


Practical Absurdity

But even if, by extending justice to nonhuman animals, we do not “corrupt that which is appropriate, by the introduction of what is foreign”, are we perhaps indeed entering a blind-alley? The second Stoic allegation claims that from the acceptance of such extension it necessarily follows, either that we act unjustly by not sparing animals, or that, if we spare them, it will be impossible for us to live. All the more so: “We shall, after a manner, live the life of brutes, if we reject the use of which they are capable of affording…. Our nature, not being sufficient to itself, but indigent of many things, would be entirely destroyed…”

Clearly, at the core of the allegation lies a practical reductio connected with the idea that “ought implies can” - the idea, that is, that we are only obligated to perform those actions which we can perform. The notion of what we "can perform" has been understood in several ways in ethical discussions, but it seems sensible to argue that, for a morality which aims at being generally implemented, self-annihilation must undoubtedly count as an obstacle to performability. As a consequence, were it true that human beings, by extending justice to the other animals, “would be entirely destroyed”, it would be difficult indeed to ask them to do so. But of course the question is: is it true that human beings could not survive without subjugating and killing nonhumans? And the answer is obviously, No. So, if the Stoic claim is that we simply cannot live without exploiting animals, we need purse this no further.  The claim is simply false.

Perhaps, however, the heart of the attack is not this. For, while the claim about our impossibility to live is only cursory mentioned, more space is devoted to the idea that humans, if they extended justice to animals, would “live the life of brutes”. Is this a better argument? Arguably not. For the revulsion raised by this idea, depending as it does on a further element of the Stoic naturalist worldview - specifically, on the injunction to follow a “human nature” which is seen as essentially governed by rationality, and a priori opposed to animal nature - cannot, as we know, be universally defended.17 And, once stripped of its specific metaphysical background, the view that the sphere of justice should be limited by the interests of those to whom justice already applies reveals its true nature as an implicit appeal to privilege. What about the idea that, since we would (allegedly) live the life of slaves if we rejected their exploitation, we are entitled to maintain the institution of slavery?

Despite the obvious flaws of this argument, a version of it is still advanced in contemporary debates.18  The basic idea is that only the creation of clear boundaries in the granting of justice can preserve the full strength of the moral protection afforded to human beings, and that, accordingly, any blurring of such boundaries is morally wrong. Often, the argument is presented in the form of a special concern for the safeguard, in particular in medical research settings, of the weakest among us - the non-paradigmatic individuals lacking most human capacities, such as the brain-damaged or the severely intellectually disabled - whose plight would allegedly be imperilled by the inclusion into the protected sphere of some nonhuman beings. Clearly, this gives the argument an air of ethical respectability: what is more ethical than paying special attention to the most vulnerable? When, however, one realizes that the suggestion that some weak beings belonging to one’s group might lose the group’s privileges is instrumentally used to deny any like protection to even weaker beings from another group, it is easy to identify in this argument, as in its Stoic antecedent, a mere appeal to human egoism and self-complacency.


Ethical Absurdity

There remains, it seems, only a final argument which could support the Stoics’ opposition to the extension of justice to nonhumans. Here is the gist of the argument: “it is not possible for us to act unjustly towards those who cannot be just towards us”. Porphyry’s test adds that, according to the Stoics, the only escape route to the dilemma between giving up justice or giving up (the order of) our lives lies in following the ancient law by which Jove gave nonhumans licence to eat each other, and confined instead justice to humankind.

The reference to the fact that (some) nonhumans eat other nonhumans seems to prefigure a recent objection to animal enfranchisement which has been termed as the “argument from predation”. Though this objection can also be interpreted as an appeal to the “naturalness” of a sort of generalized predation - of nonhumans over other nonhumans, and of humans over nonhumans - we can here ignore this construal because we have already criticized the appeal to “following nature”. What we are left with is thus something like the following. Irrational animals, by eating each other, clearly show that they do not know of justice; human beings know of justice; no one owes justice to those who cannot give justice in return; thus, human beings should (can?) confine justice to their internal dealings. The reductio is thus clearly ethical: it would be absurd to extend justice to irrational animals because this would run counter the ethical precept of reciprocity - that old and long-lasting precept which runs though the entire contractarian tradition, and that John Rawls has recently approvingly summarized as: “giving justice to those who can give justice in return”.19

That the precept of reciprocity is old and long-lasting, however, does not mean that it is sound. And in fact, it isn’t. For though the requirement of reciprocity does contain the germ of the plausible idea that, if an individual can act justly towards you, and refuses to do so, then you may be released from any similar obligation, when it comes to individuals who, by hypothesis, cannot act justly, the situation changes radically. In this latter case, the requirement of understanding justice plays the same role as the more openly sinister contractarian requirement of equal strenght, or equal bargaining power - it sanctions the exclusion from the sphere of justice of  those who are too weak or too disadvantaged to allow for mutually advantageous conventions. In such conditions of serious imbalances in power, reciprocity clearly shows that connection with egoism that some critics have stressed.20 It is thus not surprising that, though repeatedly appealed to when it comes to nonhumans, contractarian ideas have been eliminated from human rights theory. For else, what would become of equal justice for those juvenile or disabled human beings who cannot understand what justice is?

With the collapse of the ethical reductio, we can conclude that all the components of the Stoic argument against extending justice to animal, together with their contemporary avatars, are invalid. If so, we can indeed include nonhumans within that sphere of basic justice that the current egalitarian paradigm has till now confined to ourselves - turning them from objects to subjects of rights, granting them the same institutional protection of life, freedom and welfare we grant ourselves, and banning all the exploitive practices that we deem immoral in the case of human beings.

We can, but have we also an obligation? For the Stoics’ claim was stronger than the claim that we cannot extend justice to animals. What was alleged was that the extension of what is just to animals corrupts justice. Thus, after having shown the flaws of the objection, we shall turn to the last and more challenging part of our critique.



The conclusion that justice must be extended to nonhumans is supported by the force of an ad hominem argument, in the Lockean sense of an argument from commitment emphasizing consequences drawn from the opponents’ own principles.21 More precisely, its rationale lies in intra-human egalitarianism’s rejection, as grounds for different treatment, of appeals to metaphysical backgrounds, to what is “natural”, to biological make-ups, to privilege and to the requirement of reciprocity.

Using this conclusion as a stepping stone, we can now defend the view that, if justice can be rightly extended to nonhumans, it ought to be so extended, lest it no longer be considered as justice. On this view, far from being destroyed by such extension, justice turns out to be destroyed - or, to borrow from the Stoic jargon, “confounded” - by the opposite course, that is, by the endeavour to limit it to human beings.


Mill’s Argument

Can a society be considered just when justice is granted to all human beings even in case nonhumans are still excluded from it? Let’s imagine a society where all the citizens have adequate food, shelter, medical care, education, work and free time; where no one is discriminated against and all have equal institutional protection and adequate self-esteem; and where all can keep to their idea of a good life, while conflicts are settled peacefully. Such a society, however, exploits nonhuman animals. Can such a society be described as just? Can we say that, at least within the boundaries of the intra-human community, justice is truly present? An indication in the sense of a preliminary negative answer can be detected in John Stuart Mill.

In the essay The Enfranchisement of Women, probably written four-handedly with Harriet Taylor, Mill advances an important claim. Directly addressing “those Radicals and Chartists.... who claim what is called universal suffrage as an inherent right, unjustly and oppressively withheld from them”, he states that the women’s request for civil and political equality is - indeed, must be - their direct business. For with what rationality, he retorts, can the suffrage be termed universal, while half the human species is excluded from it? Isn’t to declare that a voice in the government is the right of all, and demand it only for a part - the part to which the claimants themselves belong - to renounce even the appearance of principle? Mill’s conclusion is that “the Chartist who denies the suffrage to women is a Chartist only because he is not a lord; he is one of those levelers who would level only down to themselves”. 22

This allegation clearly applies to the problem of justice and nonhumans as well. True, while Mill and Taylor could somehow take for granted the view that women are part of those “all” to whom a voice in the government pertains, the same does not hold in the case of animals. However, our argument has shown that, though not yet included in the current egalitarian paradigm, the view that (many) animals are part of those “all” to whom justice pertains is already implicit in it, and needs only to be recognized, or, to use a legal term, “articulated”. In this light, justice as applied only within the intra-human realm is not universal, and cannot therefore be appealed to as a matter of principle. But a justice which cannot be appealed to as a matter of principle is not justice. It seems that, as the Chartists in Mill and Taylor’s case, those human beings who demand justice only for the members of their species, while withholding it from nonhumans, are not demanding justice - they simply aim at a better treatment for a favored group.


The Expanding Circle

We can put to test this preliminary answer by confronting it with a widely held perspective about moral extensionism which, since the late Nineteenth century, has come to be known as the “expanding circle” approach. 23 It is probably to the historian W. E. H. Lecky that we owe its clearest formulation: “At one time the benevolent affections embrace merely the family, soon the circle expanding includes first a class, then nation, then a coalition of nations, then all humanity and finally, its influence is felt in the dealings of man with the animal world”.24 A couple of years later, Lecky’s words were echoed in a famous passage by Charles Darwin: “As man advances in civilization... the simplest reason would tell each individual that he ought to extend his social instincts and sympathies to all the members of the same nation... This point being once reached, there is only an artificial barrier to prevent his sympathies extending to the men of all nations and races. ... Sympathy beyond the confines of man, that is, humanity to the lower animals, seems to be one of the latest acquisitions”.25

Of course, both Lecky’s and Darwin’s claims are descriptive in character - they purportedly refer to matters of fact. They are, however, manifestly accompanied by an approving smile, which paves the way to a more evaluative reading. And in fact, within a framework favorable to the claims of animals, appeal is often made to such a notion. If it does not advocate that there is also a normative ranking in the attribution of moral consideration, so that it is right to focus primarily on the protection of those who are closer, and then, in a diluted measure, of those in the outer layers26 - a position clearly embodying the premises of racism - the idea of an expanding circle appears to be an enlightened approach, fostering the view that our visions might be limited, and in need of correction. There is a problem, though. For the very idea of graduality seems naturally to embody a hierarchical bent. Why should those who are the latest in chronological order accept this arrangement - especially in case their turn has yet to come?

We can clarify this with an example. There still are, unfortunately, human societies that discriminate against specific ethnic groups. Let’s thus imagine one of these societies, where justice reigns among citizens, but where the “benevolent affections” of the citizens have not yet reached a particular minority group. In such a case, would we content us with saying that the circle should gradually expand, or would we feel outraged? Would we think that, while justice is still bound to be furthered according to a progressive, or step by step, pattern, it is nonetheless actually realized in the privileged part of the society, or would we claim instead, with Mill, that that justice cannot be seen as universal principle at all? If, as I tend to think, all those who believe in the principle of equality would without hesitation opt for the latter stance, we can conclude that the gradualist perspective has a sort of originary vice connected with hierarchical bias, and that, accordingly, the expanding circle approach cannot offer an alternative to Mill’s view. It is therefore worth trying to explore such view more closely.


The Limits of Justice

Why, then, should we deem that true justice cannot exist till it has reached its proper limits? Can we offer, beyond the appeal to our intuitive reactions, a more foundational explanation?

Let’s return to the case which concerns us. What is usually emphasized in the current construal of the doctrine of human rights is that the equal protection they afford is owed to all the members of our species. Equally clearly, however, it is stated that such protection is confined to humans. For example, American philosopher Richard Wasserstrom writes: “If any right is a human right... it must be possessed by all human beings, as well as only by human beings”.27 This is a phenomenon of evaluative line-drawing, and, as such, it is normatively bivalent: it has a positive side and a negative side. More precisely, it has an inclusive and an exclusive side. These two sides are logically connected - one cannot exist without the other. In other words, by its very nature, the confinement of some moral advantages to one group is ipso facto the denial of the same moral advantages to some other groups, or to a general constituency.

Of course, if the confinement of the involved advantages can be justified - as when a line is drawn, e. g., between non-sentient rocks and sentient beings - the normative bivalence of line-drawing is morally neutral. What, however, if no justification can be offered? What if it can be shown, as I have argued it is the case with the line drawn between humans and (many) nonhumans, that the members of the included group are unfairly favored? In this instance, the situation reigning outside the line is undoubtedly morally objectionable. What, then, about the situation reigning inside the line, that is, among the members of the favored group?

At first sight, it might be claimed that it is the line which is questionable, and not what happens inside it. This claim can have some plausibility, but only in situations where the moral advantages at stake are not institutional ones and the exclusive side is not officially upheld - think, for example, of groups whose members customarily treat each other decently, while taking little care of the interests of outsiders. Consider, however, what is involved when the moral advantage in question is the access to equal basic justice. When one speaks of justice in a society, one does not refer to contingent, inter-individual relationships, but to stable laws, institutions and practices. One refers, in other words, to the structure, organization and regulated life of the community.28 Accordingly, what here count as just and unjust are the basic institutional choices, and all the acts which embody them in any definite situation. Against such a background, each and all institutional gestures of justice among the members of the favored group will involve not only the inclusive, or “just”, side, but also the exclusive, or unjust, side. As a consequence, any single gesture of selective justice, by decreeing the inclusion of those admitted to equal justice and at the same time decreeing the exclusion of those who are not admitted, will confirm and reiterate the injustice. In other words, it will bring injustice directly to the heart of the life of the favored group.

If this is so, it seems that we have reached the general reason behind the claim that justice fails to be justice when it does not reach its proper limits. Any arbitrarily limited justice creates and maintains by its own existence the existence conditions of injustice. This is, I believe, the kernel of truth that lies in the famous, and apparently mystical, dictum that no one is saved until everyone is saved. What I take it to mean is that no one - no moral agent - can be seen as exempt from unjust behavior until everyone - every moral patient - can be seen as exempt from unjust treatment. Contra the Stoics, true justice can exist only if it is extended to (many) nonhuman beings



1. Porphyry, On Abstinence from Animal Food, Book I, 4-6, trans. Thomas Taylor. I have slightly modified the translation.

2. Martha Nussbaum, “Beyond ‘Compassion and Humanity’: Justice for Non-Human Animals”, Third Tanner Lecture, delivered at Cambridge University, March 6, 2003.

3. On this, see Paola Cavalieri, “The Animal Debate: A Reexamination”, in Peter Singer, ed, In Defense of Animals. The Second Wave, Blackwell, Oxford  2005.

4. Though two religious traditions meet to shape the image of justice - that of the goddes Themis, guiding social conduct, and that of the goddess Dike, guardian of the order of things - Dike in the end prevailed, as it is shown by the fact that it is to her name that the root of the words subsequently used to refer to justice can be traced back. Cfr. Pierre Guèrin, L’idée de Justice dans la Conception de l’Universe chez les premieres philosophes Grecs, Librairie Felix Alcan, Paris 1934, Preliminary Chapt.,  II ; and Jean Rudhart, Themis et les Horai, Librairie Droz S.A., Genève, 1999, Chapt. I, B, and Chapt. III, B.

5. Parmenides, The Poem, I, 11-14.

6. Aristotle, Nicomachean Ethics,  Book 5, I.[15].

7. Aristotle, Politics, Book 3, XII.

8. Cf. e.g. Chaim Perelman, De la justice, Institut de Sociologie Solvay, Bruxelles 1945, Chapt. II.

9. See Thomas Aquinas, Summa Theologica, Justice: Question #79, Article 1, Objection 3.

10. For an examination of how such strands of thought deploy the formal concept in terms of different substantive theories of equality - such as e.g. utilitarian interpretations based on the notion of welfare, or contractarian interpretations revolving around fairness - see Philip Pettit, Judging Justice, Routledge & Kegan Paul, 1980.

11. For a discussion of oikeiosis and nonhumans see William O. Stephens, “Masks, Androids, and Primates: The Evolution of the Concept ‘Person’”, Etica & Animali 9 (1998).

12.. Marcus Tullius Cicero, De finibus III 20, 67, trans. B. Inwood and C. P. Gerson.

13. For a critical analysis, see Malcolm Schofield, “Stoic Ethics”, in Brad Inwood, ed., The Cambridge companion to the Stoics, Cambridge University Press, N. Y. 2003.

14. David Hume, A Treatise of Human Nature, Oxford University Press, Oxford 1888, p. 469.

15. On this topic, cfr. the enlightening discussion of sociobiology in James Rachels, Created from Animals. The Moral Implications of Darwinism, Oxford University Press, Oxford 1990, pp. 73-79.

16. On speciesism see Peter Singer, Animal Liberation, The New York Review of Books, New York, 1990, p. 9 ff. Cf. also Paola Cavalieri, The Animal Question. Why Nonhuman Animals deserve Human Rights, Oxford University Press, New York 2001, pp. 69 ff.

17. To the considerations about the allegation of practical absurdity it should be added that, for the Stoics, the order of the Cosmos cannot suffer an ethical dilemma such as the one allegedly involved in extending justice to nonhumans. This idea is apparent in Plutarch, Porphyry’s source for some of the quoted passages, for Plutarch attributes to the Stoics the claim that: “justice could not then come into existence, but would remain completely without form or substance, if all the beasts partake of reason. For either we are necessarily unjust if we do not spare them; or if we do not take them for food, life becomes impracticable or impossible” [italics added]. In Plutarch, that is, the Stoics’ rejection of the possibility of the allegedly involved dilemma issues in the a priori  rejection of a (possible) fact - the possession of reason by the other animals.

18. See e.g. Marie-Angèle Hermitte, “Le droits de l'homme pour les humaines, les droits du singe pour les grands singes”, Le Débat 108 (2000), pp.155-192.

19. John Rawls, A Theory of Justice, Oxford University Press, Oxford 1971, p. 511.

20. See for example Arthur Schopenhauer, On the Basis of Morality, trans. E. F. J. Payne, Bobbs-Merrill, Indianapolis, 1965, p. 91, and Friedrich Nietzsche, Human, All-Too-Human, Part I, trans. Helen Zimmern, Allen & Unwin, London 1909, aphorism 92.

21. John Locke, An Essay Concerning Human Understanding, Book IV, Chapter XVII.

22. John Stuart Mill, “The Enfranchisement of Women”, in J. S. Mill, On Liberty and Other Essays, Oxford University Press, Oxford 1998.

23. On this topic, see Peter Singer, The Expanding Circle. Ethics and Sociobiology, Farrar, Straus and Giroux, New York 1981.

24. W. E. H. Lecky, History of European Morals from Augustus to Charlemagne, George Braziller, N. Y. 1955 [1869],  vol. I, p. 285.

25. Charles Darwin, The Descent of Man, John Murray, London 1871, pp 100-1.

26. Something of along these lines can be detected e.g. in Mary Midgley, Animals and Why They Matter, The University of Georgia Press, Athens 1983. p. 124.

27. Richard Wasserstrom, “Rights, Human Rights and Racial Discrimination”, in James Rachels, ed., Moral Problems, 3rd. ed., Harper & Row, N.Y. 1979, p. 8.

28. See e.g. Thomas Pogge, “How Should Human Rights Be Conceived?”, Jahrbuch fuer Recht und Ethik, vol. 3 (1995).


* This paper was presented on June 12th, 2006, at the London School of Economics as a part of the Forum for European Philosophy’s series of Public Lectures “The Lives of Animals”.