Martha C. Nussbaum, Justice for AnimalsOur Collective Responsibility

A chimpanzee cannot sue in a United States court. Sit with that for a moment. Not because chimpanzees lack grievances — there are documented cases of chimpanzees held in conditions that, applied to humans, would constitute torture — but because the law does not recognize them as parties with standing. They are objects of protection at best, never subjects of rights. Martha Nussbaum's book, Justice for Animals, is a philosophical attempt to change the conceptual foundation that makes that sentence feel normal. Terence Burnham's review gives us a rigorous map of what that attempt looks like, where it succeeds, and where it strains. Start with the law as it actually is, because Nussbaum does. She identifies three federal statutes as the structural backbone of U.S. animal protection. The Migratory Bird Treaty Act of 1918, enacted through a treaty with Canada, declares it unlawful at any time, by any means or in any manner, to pursue, hunt, take, capture, kill, or attempt to kill migratory birds. That language is sweeping. In practice, it is complicated by licensing regimes and crop-specific exemptions, so whether shooting geese on an agricultural field is legal depends on the specific permit structure in place. The Animal Welfare Act of 1966 sets minimum humane treatment standards — feeding, watering, ventilation, and veterinary care — for covered warm-blooded animals, and it contains a flat ban on practices in which animals are made to fight. But the Animal Welfare Act has two critical gaps: it explicitly permits euthanasia of healthy animals, so killing a healthy dog is legal under federal law, and it exempts the food industry entirely. Cattle slaughtered for beef fall outside its reach. The Marine Mammal Protection Act is more aggressive — it prohibits not just killing but injuring marine mammals in the wild — and that prohibition has teeth. In litigation over military sonar, the Ninth Circuit found at least one sonar program unlawful because it interrupted whale behavior and thus implicated the Marine Mammal Protection Act's ban on injury and disturbance. Beyond those three statutes, there are hundreds of additional laws, including the Endangered Species Act. On paper, the patchwork is substantial. In practice, Nussbaum identifies three failure modes. Enforcement is weak — she writes that existing laws are "relatively rarely enforced." Coverage is inconsistent: gestation crates for pregnant sows remain legal across much of the United States while the European Union has prohibited them. And some states have gone further in the wrong direction, enacting so-called ag-gag laws that make filming the killing of animals in food production facilities illegal — so exposing how animals are treated can itself be punished. The third failure mode is standing, and it is the most structurally important. Animals generally cannot be plaintiffs. People cannot generally sue on behalf of animals. Environmental organizations like the Natural Resources Defense Council have navigated this constraint successfully in specific cases, but each victory requires careful procedural positioning, and many attempts to obtain judicial relief for animals fail on standing grounds alone. The result is a landscape where meaningful statutory language sits behind a procedural wall that keeps most harms from ever reaching a court. That gap — between what the law says and what courts can enforce — is the exact space Nussbaum's Capabilities Approach is designed to fill. The Capabilities Approach, originally developed by Amartya Sen and extended by Nussbaum, defines injustice as the wrongful blocking of striving. The key phrase from Burnham's summary of the book is that "injustice centrally involves significant striving blocked by not just harm but also wrongful thwarting, whether negligent or deliberate." This is not welfare maximization. The Capabilities Approach is opportunity-focused, not outcome-focused. It does not ask whether an animal is happy; it asks whether an animal has access to the conditions necessary to pursue the life characteristic of its species. The operational mechanism is a species-specific list of central capabilities, each list functioning as a constitutional bill of rights for that species. Nussbaum provides the human list as an anchor: ten central capabilities, including "not dying prematurely" and "to be able to imagine the situation of another." One item — the fourth capability, covering senses, imagination, and thought — is reproduced in full in Burnham's review, and it is worth hearing. It includes: "Being able to use the senses, to imagine, think, and reason — and to do those things in a 'truly human' way, a way informed and cultivated by an adequate education, including, but by no means limited to, literacy and basic mathematical and scientific training. Being able to use imagination and thought in connection with experiencing and producing works and events of one's own choice, religious, literary, musical, and so forth. Being able to use one's mind in ways protected by guarantees of freedom of expression with respect to both political and artistic speech, and freedom of religious exercise. Being able to have pleasurable experiences and to avoid non-beneficial pain." That is what a capability looks like when it is fully articulated. Now multiply it. Nussbaum proposes analogous lists for at least every species of mammal, bird, and bony fish that meets her sentience criteria. Burnham cites Pimm and colleagues and Burgin and colleagues for the species counts: at least six thousand mammal species, nine thousand bird species, and ten thousand bony fish species. That is a minimum of twenty-five thousand species-specific capability lists, each requiring development by human experts, legal adoption, national instantiation, and enforcement infrastructure. The scale is not incidental — it is the logical consequence of applying the framework consistently. How does this differ from standard welfare economics? In mainstream welfare economics, Burnham writes, concern for non-human animals appears only in the minds of humans alive today. The framework values human happiness. Non-human animals enter the calculus only through human willingness to pay for their protection. Nussbaum rejects that structure at its root. The Capabilities Approach does not run animal welfare through human preferences. It asks directly what conditions each sentient creature needs to pursue its characteristic form of life, and it defines justice as the obligation to secure those conditions. The goal of policy, in Nussbaum's formulation, is to protect and enhance the capabilities of each and every one. The philosophical lineage matters here. Burnham reports that Nussbaum engages Epicurus, Aristotle, and Rawls and draws on Christine Korsgaard's Aristotelian reading of Kant to open space for animals within a Kantian ethical framework. The argument is that sentient creatures are agents who strive, and that striving generates a claim to justice that does not depend on human empathy or on proximity to human cognitive capacity. This is the move that distinguishes Nussbaum from both the utilitarian tradition and from narrower sentience-based accounts. But here is where Burnham's review introduces genuine intellectual friction. Philosophy and biology do not necessarily converge on the same description of animal life. Evolutionary logic explains animal behavior in terms of reproductive success, not flourishing. The elephant seal does not fail to flourish when a dominant male monopolizes breeding opportunities and peripheral males are excluded — from a Darwinian perspective, that is the system working as selection shaped it. Burnham presses this point directly: does a framework grounded in Aristotelian striving map cleanly onto animals whose behavioral repertoire was sculpted by selection pressures indifferent to individual welfare? The Capabilities Approach borrows the vocabulary of flourishing from Aristotle, but Aristotle did not have Darwin. Whether those two frameworks can be reconciled without equivocation is a question Burnham leaves productively open. The welfare economics critique runs alongside this. Standard policy operates through cost-benefit analysis, and animal welfare enters that analysis only through human willingness to pay estimates. Nussbaum's framework explicitly rejects that — she does not want the rights of a chimpanzee to depend on how much a human is willing to pay to protect it. That is a principled rejection, but it comes at a cost: it means the Capabilities Approach cannot plug directly into the dominant mode of policy evaluation. Advocates for the framework will need alternative institutional mechanisms, and the book does not provide them. This is the strategic tension Burnham centers in his analysis, and it is framed around a direct comparison with the Great Ape Project. The Great Ape Project does not attempt a universal constitutional order. It selects four non-human species — chimpanzees, bonobos, gorillas, and orangutans — on the basis of phylogenetic proximity to humans, and it seeks three concrete rights: the right to life, protection of individual freedom, and freedom from torture. Three rights, four species, translatable into law now. Burnham characterizes this as explicitly biological, using knowledge of phylogeny rather than philosophy, and he treats it as a case study in how selective targeting can generate immediate reforms. The trade-offs are real in both directions. The Capabilities Approach's comprehensiveness is a moral virtue — it refuses to privilege cognitively complex species arbitrarily, and it insists that a river otter or a bony fish has a claim to justice that does not derive from resemblance to a human. But comprehensiveness is also a practical liability. Twenty-five thousand species-specific capability lists, national adaptations, and new standing rules for each — the machinery required is enormous, and while the world builds it, the harms continue. Burnham's concern is that the perfect becomes the enemy of the good: an ideal framework that requires decades of development may deliver less relief than a targeted campaign that delivers three concrete rights to four species within a legislative session. The Great Ape Project has its own liability, though. By grounding rights in phylogenetic proximity, it implicitly encodes a hierarchy of moral worth — great apes matter more because they are more like us. That is precisely the speciesist logic Nussbaum's Capabilities Approach is designed to dismantle. A framework that protects chimpanzees because they are cognitively sophisticated leaves pigs, cattle, and fish without principled protection, and those are the animals suffering at the largest scale. Burnham also asks whether the Capabilities Approach is operational. Nussbaum explicitly eschews detailed step-by-step instructions for how to transition from current law to the framework's final state. She characterizes the book as articulating an attainable ideal that directs practical efforts, not as a legal drafting manual. Burnham reads this as aspirational by design — Justice for Animals plants an ideological flag and supplies a philosophical end-state, but it does not provide the enforcement mechanisms, cost estimates, or legal drafting templates that courts and legislatures require to act. Courts need clear, enforceable rules. Capability lists, however philosophically sophisticated, need translation into the kind of determinate standards judges can apply. The wild-animal question crystallizes this problem. Nussbaum asks whether humans should intervene to improve outcomes for animals in nature. It is a serious question the Capabilities Approach seems to imply — if a predator kills prey in ways that thwart the prey's characteristic striving, does justice require intervention? Burnham treats the question as unresolved in the book, and the unresolved status is telling. The framework's logic pushes toward an affirmative answer, but the practical implications — human management of predator-prey dynamics across ecosystems — strain credibility. That strain is a signal that the framework may require additional constraints that Justice for Animals does not supply. Burnham's concluding assessment is even-handed. He acknowledges the book as a serious contribution, grounded in classical thought and philosophically rigorous in a way that distinguishes it from advocacy campaigns built on empathy and lobbying strategy. Nussbaum is not asking readers to feel sorry for animals. She is arguing that sentient creatures have a claim to justice that flows from what they are, not from how much humans like them. That is a different kind of argument, and it belongs in a different kind of conversation — one conducted in constitutional law schools and international treaty negotiations, not just in the offices of nonprofit organizations. The legal standing implication is concrete: Nussbaum argues that for capability lists to have force, animals must have the right to go to court as plaintiffs. That would require a transformation of legal doctrine more fundamental than any of the statutory reforms Burnham surveys. The gap between that proposal and the current landscape — where even well-resourced organizations struggle to establish standing on behalf of whales — measures the distance between the Capabilities Approach as a philosophical ideal and as enforceable law. The book's last paragraph calls for readers to become lovers of animal life. Burnham closes his review by asking whether that closing appeal is a philosophical argument or a sermon. It is a sharp question. It does not have an easy answer. Nussbaum has constructed an elaborate and internally consistent philosophical framework, but its persuasive force in policy settings may ultimately depend on something the framework itself cannot supply: the kind of moral urgency that moves legislatures and courts before the philosophical machinery is fully built. What Burnham's review makes clear is that the Capabilities Approach represents the most philosophically serious attempt to date to answer the question the legal landscape poses. The laws on the books protect some animals some of the time. Enforcement is weak. Standing is restricted. The animals suffering most intensely — in agriculture, in laboratories — are largely outside the reach of current remedies. Nussbaum's framework says: here is what justice would look like if we were serious about it. The distance between that vision and current reality is not an argument against the vision. It is a measure of the work that remains. This lecture was created by ennepō. Go to https://ennepo.ai to Discover, Create and Follow the latest research in your field. Read when you can. Listen when you want to.