Animal Ethics in Philosophy: How Descartes, Kant, and Darwin Influenced the Ethics of What We Eat
Introduction: The Diner's Dilemma
People love their pets and their cheeseburgers. They also hate dwelling on the irreconcilable moral contradictions hidden in those two passions. Lucky for them, the system is set up so they don't have to dwell on it too much. Who would have thought the essential act of eating meat was so morally fraught? And who would have thought such misery could happen in our progressive age?
I want to explore animal ethics and philosophy in the context of three influential thinkers. I'll argue that today's mealtime morality rests on three philosophical pillars: a Cartesian, a Kantian, and a Darwinian.
Descartes' philosophy anticipated factory farming. Here animals were little more than soulless automatons, forever denied ethical consideration. He dismissed them as fleshy machines unable to experience pain or suffering. Herein lies the origins of the modern CAFO (Concentrated Animal Feeding Operation) and all the horrors it inflicts on the sentient critters destined to be our food. This is the first pillar.
Kant offers the second. He highlights our contradictory and hypocritical attitude toward the animals we eat. We adore some while eating others raised in those hellish CAFOs. Billions of livestock like cattle, pigs, and chickens suffer and die every year, leading short lives of windowless misery for the consumer's dining pleasure. Yet we treat dogs and cats like family (sometimes even better), giving them names and loving them for their unique personalities. We deeply care for them and grieve when they are gone.
Finally, Darwin's theory of evolution opened up a third way, setting the stage for today's animal rights movement. He revealed the evolutionary similarities between homo sapiens and other life. His most significant revelation was to prove we're not created in God's image but are merely one branch on an evolutionary tree of life.
If this is true, no absolute separation exists between man and beast, only continuities. We are all animals, different in many ways but ultimately comprised of the same stuff. Humans share identical biological characteristics as other animals, such as the ability to experience pain and suffering. This is key.
Viewed only online, our culture appears as a schizoid mix of gooey compassion for our furry little companions and all the adorably human-like things they do. So cute! So relatable! And indeed, they are.
Yet working parallel to all this is a relentless appetite that piteously devours animal flesh without a second thought. This flesh was once as adorable as our kittens and puppies and bunnies. But there is a difference. Before becoming our food, they live far from our empathetic gaze, and so end up invisible abstractions. That this is all intentional fascinates me, as do the contradictions inherent in a system that allows such compartmentalized compassion to exist alongside such remorseless cruelty.
That's what I'll explore below.
Descartes: Origins of the Modern Cartesian Model
René Descartes is most famous as one of the founders of modern philosophy. He also infamously nailed the paws of his wife’s dog to a board to dissect it alive. All in the name of science! According to him, the dog’s cries were no different than the springs and wheels of a clock automatically reacting when dismantled (Joy 109). He acknowledged that animals were alive and experienced sensations. “For I do not deny that any animal has life – which, I claim, consists only in the heat of the heart” (Descartes 175).
However, he rejected that they perceive pain or engage in rational thought. On the contrary, they existed as little more than mechanical automatons incapable of experiencing pain (174). He took it a step further, stating only a mind with an intellect could think. If this were not true, we would not have a will; without that, a rational being could not exist. Will, reasoning, and intelligence set humans apart in the Cartesian worldview (Broughton 408).
This division left everything else excluded from ethical consideration. Descartes thus contradicts the intuitions that tell us this is otherwise. But those intuitions only work when we can interact directly with animals. When we don't interact, or can't, then the cold Cartesian worldview can flourish, if such a word can be used to describe what goes on in factory farms.
In Omnivore's Dilemma, Michael Pollan comments on the moral aspects of factory farmed livestock.
"It is not easy to draw lines between pain and suffering in a modern egg or hog operation. These are places where the subtleties of moral philosophy and animal cognition mean less than nothing, indeed where everything we’ve learned about animals at least since Darwin has simply been…put aside. To visit a modern Concentrated Animal Feeding Operation (CAFO) is to enter a world that for all its technological sophistication is still designed on seventeenth-century Cartesian principles: animals are treated as machines – “production units” – incapable of feeling pain. Since no one can believe this anymore, industrial animal agriculture depends on a suspension of disbelief on the part of the people who operate it and a willingness to avert one’s eyes on the part of everyone else" (Pollan 317).
Pollan is right to compare the French philosopher and factory farming. The image of the efficient mechanical factory and animals treated as production units takes us back to Descartes and his wife’s dog. Descartes argued that if animals cannot experience pain, we can ignore the most basic considerations for their welfare. This synchs up quite nicely with modern capitalism. Animal welfare is secondary to profit. Flesh becomes just another product the factory produces.
Market demands for affordable meat and dairy mean ethical considerations for those living production units are set aside to keep grocery store shelves stocked. The Cartesian ideology offers consumers the cognitive framework needed to set aside sentimentality in the name of mass production. "Well, no big deal since they don't suffer anyway. Let's have some more bacon. Yum,"
Peter Singer argued, “The core issue is the commercial pressures that exist in a competitive market system in which animals are items of property, and the conditions in which they are kept are not regulated by federal or state animal-welfare law” (Singer, The Ethics 55).
Worldwide, factory farms slaughter over 70 billion animals annually. Getting enormous quantities of meat and dairy to market as cheaply as possible means most livestock leads short, crowded lives of misery. It is standard industry practice for chickens to have their beaks cut and pigs to have their tails docked to prevent injuring each other. Why do they hurt each other? Because of the stress of living in dark, crowded conditions from the day they are born until the day they die.
Melanie Joy states, “From a profit standpoint, animal welfare is a barrier to profit, as it costs less to mass-produce animals and discard those who die prematurely than it does to care for them adequately” (Joy 39).
The Cartesian model, as practiced in agribusiness and medical labs over the last three-quarters of a century, gained a veneer of scientific credibility thanks to the strong influence of B.F. Skinner’s behavioral psychology. Skinner’s ideas represented an updated version of Descartes’ mechanistic view of animal consciousness.
According to Behaviorism, animals (and people) react to environmental stimuli, and that's it. In this model, anthropomorphizing their behavior allowed subjective bias to creep in, which could compromise objective research.
The result was the banishment of descriptive language that seemed to anthropomorphize test subjects like rats, rabbits, and monkeys. By rejecting anthropocentric descriptors to describe observed animal phenomena like emotion, empathy, and sensitivity, science set up cognitive and semantic barriers reinforcing Cartesian indifference.
In The Better Angels of Our Nature, Steven Pinker relates with a guilty conscience about his time as an assistant in a research lab that tested Skinner’s theories of operant conditioning.
"To motivate the animals to work for food, we starved them to 80 percent of their free-feeding weight, which in a small animal means a state of gnawing hunger. In the lab next door, pigeons were shocked through beaded key chains that were fastened around the base of their wings; I saw that the chains had worn right through to their skin, exposing the muscle below. In another lab, rats were shocked through safety pins that pierced the skin of their chests. In one experiment on endorphins, animals were given unavoidable shocks described in the paper as “extremely intense, just subtetanizing” – that is, just short of the point where the animal's muscles would seize up in a state of tetanus" (Pinker 455).
Pinker finishes this disturbing anecdote by noting how one of his fellow researchers sometimes expressed anger by picking up the nearest rat and throwing it against the wall (455).
Likewise, Michael Shermer relates a story of his time in a lab. His job was disposing of the lab rats that were not needed anymore. Of course, by then, Shermer had named some of the rats and found the prospect of killing them unappealing.
“But then the experiment is over and the time comes to dispose of the subjects, which in the case of the rats was done by…I can barely type the words…gassing them with chloroform in a large plastic bag” (Shermer 276).
Indeed, this Cartesian model remained dominant in research labs until the early 1980s. Since then, regulatory oversight has mitigated the worst abuses, though experimentation continues (Pinker 456). The point is that the Cartesian worldview still plays an important, though hidden role, in society today. People benefit from the cheap food factory farms produce and the medical technologies developed from lab testing. Out of sight, out of mind, is a time-tested way to commit atrocities without provoking the moral disgust of the public. All for the greater good...the ends justify the means...and so on, are some defenses you'll hear for these practices.
Going back to Descartes: Vivisecting a live dog only horrifies us because it is a particular example we can imagine. Anyone doing this to a dog today would be condemned as a monster and subject to criminal prosecution. What Descartes did is multiplied millions of times a day, though most shrug since this is happening out-of-site in windowless buildings where it exists as little more than an abstraction.
Suffering tastes good, and even more so when I don't have to see it or smell it or hear it.
Next, I want to show how Kant's ethical compartmentalization creates an uncomfortable psychological tension between the costs versus the benefits of these practices.
The Kantian Model and the Ambivalence of the Modern Consumer
Immanuel Kant seems like more continuity with the past than anything novel. Similar to Aristotle, he stated, “But since animals exist only as means, and not for their own sakes, in that they have no self-consciousness, whereas man is the end, such that I can no longer ask: Why does he exist?, as what can be done with animals, it follows that we have no immediate duties to animals; our duties towards them are indirect duties to humanity” (Kant, Lectures 212).
Like Descartes, Reason was paramount. Only a rational being can be moral and treat other rational beings as ends rather than means. Irrational beings - which are everything else - were not moral since they could not reason.
They were therefore excluded from ethical consideration (Kant, Ethical Philosophy 35-36).
But like Aquinas, Kant argued that people should avoid animal cruelty lest it leads to sadism, which (of course) would be unethical.
Andreas-Holger Maehle sums up Kant’s position on animals: “Animals suffering as such was not ethically relevant here, but only the effects of cruelty on human morality” (Manning 92).
That is true but there's more to it. Kant's emphasis on avoiding animal cruelty, whatever the motive, contrasts with Descartes’ utter indifference. There is some room here for common ground with later animal rights advocates. If we get past his exclusion of animals from our moral calculus, there is a limited animal ethic here, representing an advance from the cold Cartesian thinking. It may appear paradoxical, but Kant’s guidance is that we should not mistreat animals, if not for their sake, then for ours.
He cites the example of an old dog who has faithfully served his owner for years. According to Kant, the comparable human behavior on the dog’s part is faithful loyalty. Thus, the owner has the ethical duty of looking after the dog in its old age rather than killing it for being useless.
Kant writes, “So if the acts of animals arise out of the same principium from which human actions spring, and the animal actions are analogs of this, we have duties to animals, in that we thereby promote the cause of humanity. For a person who already displays such cruelty to animals is also no less hardened towards men”(212).
Kant is hinting here that animals actually suffer when mistreated. Only a monster willfully harms helpless creatures. Someone who can inflict pain or death on an animal with cold indifference is a short step away from doing it to people. Though in Kant’s moral universe, people stand above animals because of Reason, their suffering at least merits some limited consideration.
Julian Franklin agrees with this interpretation: “If the infliction of pain and death on animals, without legitimating cause, is not cruel per se, why should it harden us toward humans? And if it does, in fact, harden us toward humans, it must be because we have become insensitive to the wrongful harming of animals” (Franklin 37).
Kantian ambivalence represents a significant tension in the modern consumer. Kant felt that animals exist as a means to our ends and therefore did not deserve ethical consideration. By this reasoning, a justification for unrestricted animal use that is congruent with Cartesian factory farming seems to follow. However, he also said we shouldn't abuse animals. This appears to argue against the status quo.
This contradictory friction between conscience and appetite defines the attitude of most people. It often goes unresolved, as avoidance is made all the easier because what happens at factory farms stays hidden at factory farms. Still, one cannot help but feel that Kant represents a moral improvement over Descartes regarding how we treat animals. Maybe animals are not worthy of equal consideration by Kantian logic, but we still have to treat them well.
But that's easier said than done. The Cartesian system shields the Kantian from too much uncomfortable knowledge. The suffering of cattle, chickens, and pigs is so spatially remote it becomes impossible to conceptualize. The closest the average consumer ever comes to a CAFO or a slaughterhouse is while perusing the grocery store's neatly packaged, bloodless meat section.
Dr. Melanie Joy was spot on when she wrote: “Indeed, it is only because of technology that widespread meat production is possible: modern methods enable us to eat billions of animals every year without witnessing a single part of the process by which these animals become our food” (Joy 124).
Here is the Kantian food model in all its glory: People live two parallel but contradictory ethical lives concerning animals. On the one hand, most truly love their pets and establish deep emotional bonds. The numbers back this up in America, the country with the highest pet population in the world, at just over 140 million dogs and cats. Around 66% of Americans own pets; 85% of dog owners and 76% of cat owners consider their pets as part of the family.
I would wager the percentage of pet owners willing to dine on their furry family members would be around zero. But nary a thought on the chopped-up bits and pieces of other animals that end up on their dinner plates.
“We tolerate this schizophrenia because the life of the pig has moved out of view; when’s the last time you saw a pig in person? Meat comes from the grocery store, where it is cut and packaged to look as little like parts of animals as possible” (Pollan 306).
Pollan calls this modern Kantian ambivalence toward animals the "Omnivore’s Dilemma" because the ethics of what we eat present a constant tension between the nobility of our good intentions and the consequences of our actions. Many otherwise decent and kind people can sometimes have glaring moral blind spots. This is one of them.
Covering the 2003 Maine Lobster Festival for Gourmet Magazine, David Foster Wallace expressed these contradictions when he mused in a now-famous essay called "Consider the Lobster" about the festival’s star attraction. Wallace, an omnivore before and after the article, nevertheless expressed how misgivings often arise when one stops for a moment to challenge underlying assumptions about what some other creature is experiencing.
"How do people who view themselves as morally responsible justify their participation in the current food production system? That is a difficult question for many to answer, or even face. The more important point here, though, is that the whole animal-cruelty-and-eating issue is not just complex, it’s also uncomfortable. It is, at any rate, uncomfortable for me, and for just about everyone I know who enjoys a variety of foods and yet does not want to see herself as cruel or unfeeling. As far as I can tell, my own main way of dealing with this conflict has been to avoid thinking about the whole unpleasant thing. I should add that it appears to me unlikely that many readers of Gourmet wish to think hard about it, either, or to be queried about the morality of their eating habits in the pages of a culinary monthly" (Wallace).
Consider Wallace an uncomfortably aware and conflicted Kantian. In any case, he was right: Many do not wish "to think hard about it...or be queried about the morality of their eating habits." Joy has a theory that people engage in a psychological trick called "de-individuation" that helps them reconcile the contradictions they can't flat-out ignore. “De-individuation is the process of viewing individuals only in terms of their group identity and as having the same characteristics as everyone else in the group” (Joy 119).
De-individuation becomes much easier when our role is limited to consumption remote from the production process. Wallace's essay was a noble attempt to confront mass de-individuation, not directed at a bird or mammal where some sympathy might easier be found, but at the alien and insect-like lobster.
Consider a simple thought experiment to highlight Joy's point: Would we allow our beloved pet to be treated the same way as a factory-farmed hog or even a lobster? Really, what's the difference between the two?
I've asked these questions many times over the years and have never received a satisfactory answer that gets at the heart of the matter. That answer, it seems clear to me, is that one is seen as an individual. The other is not. That's it. We are biologically hardwired to form emotional connections with what we know and experience firsthand while rationalizing unethical behavior for those outside our circle of direct experience (De Waal, Age of Empathy 221).
The modern Kantian consumer tries to sustain an illusion that it all somehow makes sense, coming up with reasons that sound convincing. Like, for example, eating meat (or not) is merely a lifestyle choice, no better or worse than Vegans who choose a plant-based diet. Or, livestock exists as food for us; therefore, it's ok to eat it. Or, you eat what you want and I eat what I want and we all must respect each other's choices because...freedom. These are just a few of the morally vacuous platitudes I've heard a thousand times. They are not even superficially convincing to anyone who puts any thought into it.
And so it goes: Cartesian factory farms thrive in the shadows, propped by blissfully unaware Kantian consumers dining on cheap and tasty cruelty. At some level, the average person knows that factory farming is wrong. But they never have to think about too much or for too long.
That's on purpose.
Still, there are signs this is changing due to the recent surge of a third, more hopeful way: the Darwinian.
The Modern Darwinian Model and the Expansion of the Moral Arc
Charles Darwin revolutionized the way we view ourselves as a species. As we've seen, Western tradition has long held that human nature contains intrinsic differences from the rest of the animal kingdom.
Darwin shattered this myth by showing how interconnected all life is. Humanity, like the chimpanzee, like the dolphin, like the lobster, like everything, is a product of evolution.
E.O. Wilson describes how pervasive the Darwinian view of life has become. It knocked humanity off its high perch, previously right below God and the angels, and demoted us to just another branch on the tree of life.
“The general traits of human nature appear limited and idiosyncratic when placed against the great backdrop of all other living species. Additional evidence suggests that the more stereotyped forms of human behavior are mammalian and even more specifically primate in character, as predicted on the basis of general evolutionary theory” (Wilson 32).
Indeed, Darwin went so far as to speculate that animals shared the same traits as humans, like sympathy, grief, curiosity, excitement, and boredom, to name but a few (Darwin 100, Descent). To understand how radical this is, contrast the following quote by Darwin in the context of what we've seen so far with Descartes (i.e., animals as mechanical automatons) and Kant (animals as means to ends):
“The lower animals, like man, manifestly feel pleasure and pain, happiness and misery. Happiness is never better exhibited than by young animals, such as puppies, kittens, lambs, &c., when playing together, like our own children” (89).
This paradigm-shifting assertion of humanity’s direct relatedness ("...like our own children") to all other life on Earth provided the intellectual foundation to re-conceptualize our ethical stance toward other life.
Peter Singer, a contemporary philosopher and a leading thinker in the animal liberation movement, echoes Darwin and expands upon it. At the heart of Singer’s philosophy is that man and beast share an ability to feel pain and suffer. “If a being suffers there can be no moral justification for refusing to take that suffering into consideration” (Singer 8).
If this is true, then beliefs that animals do not experience pain (Descartes) or do not have interests (Kant) begin falling apart. Since the 1970s, when Singer and others like him began pointing this out, the Cartesian and Kantian models have been on the defensive.
Steven Pinker shows how our ethical stance toward animals represents one aspect of a larger “rights revolution” that has taken place over the last two centuries and includes race, sex, and sexual orientation. He credits Peter Singer for the thesis of his book, The Better Angels of Our Nature, which says,“…human beings were endowed by natural selection with a kernel of empathy toward kin and allies, and have gradually extended it to wider and wider circles of living things, from family and village to clan, tribe, nation, species, and all of sentient life” (Pinker 465).
According to Pinker, beginning with the rise of Singer's (and others) ideas in the 1970s, Western culture has developed less tolerance for animal cruelty. Modern legislation has curbed many abuses in animal testing and, to a much lesser extent, factory farming. Another book by Michael Shermer, The Moral Arc, makes a similar point but uses Darwinian concepts to make his case.
“A moral system based on continuous rather than categorical thinking gives us a biological and evolutionary foundation for the expansion of the moral sphere to include nonhuman animals, based on objective criteria of genetic relatedness, cognitive abilities, emotional capacities, moral development, and especially the capacity to feel pain and suffer” (Shermer 263).
This is not quite an argument for Singer's ethical Veganism. Still, it is not far off because, for the first time, it advocates for more awareness of how our decisions might harm other sentient life. Remember, these views are now coming from mainstream scientists like Pinker and Shermer and not from hippy-dippy radical animal rights activists. The Overton Window has shifted in favor of the Darwinian model over the last forty years.
What was once done thoughtlessly is now remembered with embarrassment. Former lab research assistants like Shermer and Pinker each recount participating in animal experiments with genuine guilt and regret.
Here is how Pinker starts his story about working in an animal lab: “Let me tell you about the worst thing I have ever done” (Pinker 454).
Likewise, Shermer recalls his work in a testing lab as “…one of the most dreadful things I ever had to do” (Shermer 276). These two examples show how much the ground has shifted in a very short amount of time. Many who participated in the Cartesian model look back on those times with shame and horror.
There are hints a similar shift in thinking is happening in the general population, with more widespread support for legislation protecting animals from the worst abuses in factory farms and laboratories (Shermer 284-288). Alternative options like plant-based milk and meat are carving out larger market shares. There is reason for cautious optimism for the future.
Final thoughts: Animal Ethics and Philosophy
This essay's purpose is not to argue how one of these paradigms will triumph anytime soon. It should be clear at this point, however, that I endorse a more Darwinian-friendly view. However, for most Americans, all three continue to play a role, though sometimes in contradictory ways.
And if specific trends show encouraging signs for the future, others are downright depressing. The Cartesian model supplies modern society with cheap and abundant animal products, though at a substantial moral and environmental cost. In 2022, an estimated 99% of all farm animals reside in factory farms, often in deplorable conditions.
The default response for the vast majority is to morally compartmentalize the mind to wall off the contradictions from each other. That way, people can call themselves animal lovers while consuming meat and dairy daily. It works pretty well when over 90% of the population plays the same game. Who will challenge them? Just picture the average American family sitting down for a steak dinner with the family pets hovering on the margins to notice how intertwined all three models remain.
A growing consciousness of the similarities and continuities between all species, including man, should not downplay the continuing dominance of the Cartesian and Kantian models. The moral dilemmas raised by the Darwinian model, compelling as they are, remain muted in a society where roughly 95% of the population still consumes animal products with unquestioning devotion. As more people worldwide enter the middle classes and have more disposable income, they will undoubtedly aspire to eat a meat-heavy diet like we do in the developed world.
Moreover, dramatic shifts in ethical behavior do not come quickly when one must sacrifice personal pleasures for what appears to be mere abstractions. "What difference will one person like me make by not eating meat? And at what social cost will it be to MY happiness? It seems like so much sacrifice for so little! So then, why do it?" The apparent futility of it all is often enough to smother any motivation to change one's habits.
In this way, even a valid argument against eating meat and dairy is often countered by habit, societal norms, economics, and safety in numbers (herd mentality). This makes changing the status quo daunting, at least for the near future, and should temper any Vegan illusions of an impending plant-based utopia.
The adage that people want to eat sausage, not watch it made, is literally true here and explains how acceptable factory farming remains, at least as long as we don't know too much about it. But you cannot supply endless and affordable animal products for an affluent and urbanized society by treating tens of billions of livestock "humanely." The current paradigm depends on an economy of scale to keep shelves stocked and prices low, and that takes little account of the welfare of the livestock involved.
The producer and consumer thrive in a symbiotic relationship of cheap, abundant food in exchange for the public's 'hear-no-evil-see-no-evil' attitude. However, with a modern interpretation of Darwinian ideas by animal welfare advocates, a growing wedge between the Kantian and Cartesian models is emerging. These advocates are lifting the shroud of ignorance surrounding the methods used to produce our food.
Meatless options are now abundant in grocery stores when before they were not. New products like Beyond Meat and the Impossible Burger have bridged the taste gap between meat and plant-based meat substitutes. Most restaurants now have a solid selection of Vegan and vegetarian options. This was not the case before. These are also positive trends.
As the market shifts along with our consciousness, perhaps factory farming will be a thing of the past someday. It's not enough to know about the evils of the system.
One much choose to do otherwise. Until then, nothing happens but more of the same, and more of the same is an abomination.
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First published 6 Jun 2019 - Paris, France
Updates and edits 23 Jul 23 - Falls Church, VA