Problems With the Argument From Marginal Cases and Using Sentience as a Basis for Rights

The logical case for obligatory veganism rests entirely on the Argument From Marginal Cases. This is the argument claiming there is no morally significant difference distinguishing every human from all other animals. You can’t say that humans get rights and other animals don’t because humans are intelligent, have long-term ambitions and are capable of rights/responsibilities exchanges with one another, because what about babies and the severely intellectually impaired? They have rights (don’t they?) and they aren’t intelligent, they don’t have ambitions and they can’t respect our rights in exchange for us respecting theirs.

So why do we dangle rights in front of animals and then yank them away, only to give those rights to babies and the mentally impaired, whose mental states are similar to or sometimes lower than that of adult animals? If we say “because babies and the intellectually impaired are human,” that is speciesism, and we might as well be saying that straight people are allowed to get married because they have sex with the opposite gender. Is this why babies have rights? A racism-like prejudice in favor of our own kind? Or is it something else?

According to vegans, the reason we give babies and the severely intellectually impaired rights also conveniently happens to be the one thing that other animals have in common with us: sentience. We don’t kill baby Jordy and eat him for dinner (thus giving him good reason to sing “Dur dur d'être bébé”) because that would cause him pain due to his ability to suffer. And if we can’t kill Jordy since it would hurt, then we can’t kill Babe, Wilbur, Arnold or Snowball, who also have the ability to suffer, even if they don’t sing about how hard it is to be a piggy. Thanks to babies, the intellectually impaired, the comatose and the extremely senile, the only characteristic we’re supposed to judge living beings on is sentience, which means there is no consistent morally significant difference between all humans and all animals.

Many vegans believe that the Argument From Marginal Cases makes the logical case for veganism unassailable. Well, no logical argument is unassailable if we are willing to accept moral subjectivism and arguments from selfishness. We don’t have to mandate moral principles and let them drag us to their unfortunate consistent conclusions if we’re making up morality for our own benefit – and why wouldn’t we do that, assuming there is no God or we don’t know what God expects of us? As Jesse Prinz writes, morality is based on emotions, not facts.

If we apply a selfish cost-benefit analysis to giving animals rights, veganism clearly fails, as it makes life worse for all humans. (Incidentally, veganism doesn’t even help animals either.) Since we create morality, there’s nothing stopping humans from looking at morality purely from a standpoint of how useful it is for us, and giving animals rights is nothing but an impediment for humans.

But I’m not convinced that moral opportunism is the only escape from the Argument From Marginal Cases, using sentience as a basis for rights and veganism.

In his most recent entry, animal rights professor Gary L. Francione characterizes sentience as a survival tool for living beings that move, which has the unfortunate side effect of making pain and torture possible. This, Francione argues, is why “But plants want to live too!” is a silly argument against veganism:

Plants do not have nervous systems, benzodiazepine receptors, or any of the characteristics that we identify with sentience. And this all makes scientific sense. Why would plants evolve the ability to be sentient when they cannot do anything in response to an act that damages them? If you touch a flame to a plant, the plant cannot run away; it stays right where it is and burns. If you touch a flame to a dog, the dog does exactly what you would do—cries in pain and tries to get away from the flame. Sentience is a characteristic that has evolved in certain beings to enable them to survive by escaping from a noxious stimulus. Sentience would serve no purpose for a plant; plants cannot “escape.”

Because of plants’ lack of sentience, it’s fine to pluck a petal off a living flower. Plucking the ear off a living pig is a little different because, as you might gather from the pig’s reaction, that’s painful.

This reasoning makes sense to me. I understand why a pig having sentience might be a good reason not to put a hot poker through the pig’s eye. So I can see where vegans are coming from when they say “don’t torture animals.”

Where vegans lose me is in the leap from “animals are capable of suffering” to “animals have a right to life.” Why do vegans equate an ability to suffer with having an inviolable reason to live? It’s intuitive to not want to cause pain to something capable of pain, but I’m not sure what this has to do with right to life if the life can be ended painlessly. How do vegans get from “these creatures move around and it hurts when we punch them in the snout” to “we can’t stun them and then kill them”?

The vegan answer to this is that animals have “interests,” something Francione links with sentience earlier in that same entry:

The difference between the animal and the plant involves sentience. That is, nonhumans—or at least the ones we routinely exploit—are clearly conscious of sense perceptions. Sentient beings have minds; they have preferences, desires, or wants. This is not to say that animal minds are like human minds. For example, the minds of humans, who use symbolic language to navigate their world, may be very different from the minds of bats, who use echolocation to navigate theirs. It is difficult to know. But it is irrelevant; the human and the bat are both sentient. They are both the sorts of beings who have interests; they both have preferences, desires, or wants. The human and the bat may think differently about those interests, but there can be no serious doubt that both have interests, including an interest in avoiding pain and suffering and an interest in continued existence.

Though the “plants want to live too” line of argument that Francione disputes is certainly silly, all the New York Times writers lining up to rationalize meat eating by elevating the status of plants are nearly onto something. The vegan reliance on “interests” to help animals cross the border from something we’re not allowed to torture to something we’re not allowed to kill shows why.

The “interests” argument treads into murky waters because unlike sentience, “interests” can be applied to plants. Plants don’t have a central nervous system and thus don’t suffer the way animals do, but they do have an interest in living. Otherwise why would they have defense mechanisms like protective toxins, why would they lean toward the sun and why would they spread their seeds to propagate? It doesn’t hurt a plant to end its life, but it’s clearly trying to live, which means that if interests are a bridge to rights, we have to give up plants too and starve. Or we have to stop giving moral protections to our sources of sustenance, which is what The New York Times science section hopes we do.

Plants also have “preferences” in the sense that they generally prefer light to darkness and wet soil to dry soil. They may not be conscious of these preferences, but vegans don’t say that self-consciousness is the morally relevant difference between plants and animals. That’s probably because consciousness is harder to measure and prove. We can hear a dog yelp when we pull its tail, but we can’t see that a dog consciously thinks “I’d rather be licking myself right now.”

Another kink is that vegans violate animal preferences and interests all the time: feeding a cat a vegan diet, spaying and neutering companion animals, and PETA-operated kill shelters are some examples. If even vegans don’t treat animal interests and preferences as inviolable, including biggies like the right to sex or the right to life, why can’t we eat animals if we kill them painlessly? Because it would hurt if we kicked them in the face? So why can’t we just not kick them in the face?

The animal interest in living may be more complex than the plant interest in living, but the human interest in living is more complex than the animal interest in living, so we can’t consider complexity of interest as a factor – that could be used to justify giving humans but not animals rights. It could even lead to a hierarchy of rights within humans, with those having the most intriguing lives earning a greater right to live than 9-to-5 wage slaves. We have to treat all interests in living equally if we’re not going to let self-proclaimed Übermensches bogart all the rights; therefore, to say that an animal has preferences and an interest in life does not distinguish it from plants, who are also in a biological battle to survive and have preferences, even if they can’t move or scream.

If an interest in living doesn’t give rights to plants, and sentience by itself would only seem to justify not torturing a creature, I’m not sure how you can tack “interests” and “preferences” on top of sentience and get “right to life” from there. A life’s ability to suffer still seems unrelated to whether that life is worth more than its meaty covering.

Maybe using sentience as a shorthand for the ability to feel pain is too limited. What about pleasure? Some vegans say it is a crime to kill animals because we are taking away all future opportunities for the animal to experience the joy of eating and playing. (Sex is another animal pleasure we’d be depriving them of, but vegans have to leave that one out since most of them are okay with spaying and neutering pets, which removes the possibility of future sexual pleasure.) Would it be fair to say that the reason we shouldn’t hold a blowtorch to an animal is that the animal experiences pain, and the reason we can’t end an animal’s life is that it won’t get to relish the taste of VegeCat anymore?

To me, trying to use pleasure to justify a right to life raises the same question that comes up when you try to use suffering to do the same. It’s intuitive to say that ability to suffer means we should try not to provoke that suffering, and not at all intuitive to say that ability to suffer makes painless death impermissible. Pleasure giving a right to life makes a little more sense than suffering giving a right to life, yet where exactly does an ability to experience pleasure tie into freedom from early demise? Does this mean that someone in a severely depressed mood who finds no joy in life has a right not to be tortured, but not a right to life?

The pleasure aspect of sentience seems less important to vegans anyway. The question of insects having rights is a gray area for vegans, and the sole reason they give for this is that we don’t know if insects feel pain. As fun as it must be to hop and chirp to your little cricket heart’s content, if crickets don’t feel anything when we pull their legs off, vegans don’t give them rights. Vegans don’t care about squashing the future pleasure potential of insects. They don’t eat bugs or bug products because it’s possible that insects get hurt. (Also they think bugs are gross.)

The insect question is another illustration of the incoherence of adding sentience plus interest in living and arriving at the conclusion of rights. Insects unquestionably have an interest in life. They look for food, they mate, and they flee if you try to kill them. Yet vegans deem their interest in living meaningless if insects don’t feel pain, relegating them to the same philosophical junk bin as bivalves – animals that most vegans say we are allowed to eat because they lack a central nervous system, even though they too have an interest in living. But if pain is the only concern, can’t we eat animals with a capacity for pain as long as we don’t activate their pain receptors? No, say vegans, because somehow the capacity for pain makes the creature’s interest in living take on greater and more important proportions. This is the case even though Francione frames sentience as a purely situational adaptation that lacks any relevance to meaning of life – the reason plants don’t have sentience is that it wouldn’t help them since they can’t run away. Animals are not rooted into the ground, thus they have sentience as a survival mechanism, and because of this we’re not allowed to eat them.

The only thing stopping us from immediately putting the case for obligatory veganism on the no fly list is the Argument from Marginal Cases, which vegans desperately call in to mop up all their philosophical messes. Because of this argument, vegans can say that if sentience is not a basis for rights, then we can’t give babies, the senile, the comatose or the severely intellectually impaired rights without being horribly speciesist. And if you’re anti-racism, anti-sexism, anti-ableism and anti-homophobia, do you really want to mess up your anti-oppression streak and be pro-speciesist? You were on such a roll!

So let’s see what might be wrong with the Argument From Marginal Cases.

1) The Argument From Marginal Cases is about humans, not about animals.

If humans were born moral agents and there were no intellectually handicapped or senile humans, there would be no Argument From Marginal Cases because there would be no marginal human cases to reference. If humans replicated without an infant stage, suddenly it would be morally permissible to use animals for food, clothing and entertainment. After all, we would be able to say “Moral agency is required for rights, all humans are moral agents and no nonhuman animals are.”

So eating animals would be okay if there were no humans in a coma? Why does something that doesn’t change any qualities in the animals themselves (human marginal cases or the lack thereof) determine what we can do with them?

Last year I was emailing a vegan about marginal cases and so on and I asked him that question. Here is what he said:

the argument from “marginal cases” reveals a deeper moral intuition: regardless of one’s intellect, or favorable draws in the natural (and social) lottery, harm and death are bad to anyone capable of experiencing harm and death. There isn’t a logically or morally compelling link, in other words, between my ability to reason and the badness of being in pain. If there were no “marginal cases”, I suspect that acknowledging that intuition, or giving it voice, would be more difficult. Although, our natural capacity for empathy, pre-rationally, pre-reflectively triggered at the sight of suffering, is always there, and I believe it would enter into our moral calculations. However, the deep intuition, and the sustained moral argument that follows, is relevant regardless of any actual “marginal cases”.

Or, as I would rephrase it: the Argument From Marginal Cases creates the illusion of a logical argument, putting a smarty pants disguise on what is really just an emotional revulsion at the killing of animals.

2) The Argument From Marginal Cases wouldn’t spare us its devastating illusion of logic even if we had a proven nutritional need for animal products.

If some or all humans were obligate carnivores or obligate omnivores (and plenty of humans do claim to be at least obligate omnivores), this argument requires us to eat babies, the mentally impaired, the senile and the comatose in order to be morally consistent and avoid speciesism. Yet, annoyingly, the argument does not provide guidance for how much human we would have to eat in proportion with other animals to avoid speciesism. Would we have to eat exactly equal amounts of lamb, goat, yak, frogs, chicken, ducks, each kind of fish, nutria, each kind of snake, squirrel, each kind of insect, bison, cow, pig, babies, senile people, etc. in order to make sure we are avoiding speciesism to the fullest? And do we have to be sure to eat the exact right amount of plants too in order to not be kingdomist? Seriously, what would we make of this argument if it were established that we absolutely needed to eat animal products, or if we anecdotally feel much better eating animal products?

3) The Argument From Marginal Cases requires us to “treat like cases alike,” yet babies, the intellectually impaired and the senile currently have more rights than vegans are willing to give animals; this means we either have to give human marginal cases fewer rights than most people (including vegans) are comfortable giving them, or we have to give animals more rights than even vegans are comfortable giving them.

When vegans talk about giving animals rights, they don’t mean giving animals all the positive rights that adult humans often have. In a vegan world, animals do not have a right to health care, to vote or to drive on public roads. Instead, vegans want to give animals the basic libertarian negative right: the right to be left alone. We can’t kill animals (well, unless they’re eating our vegetables), but we don’t have to take care of them either. The reason for this distinction is supposedly not speciesism.

It’s okay to give moral agents (fully functioning adult humans) a few more rights than moral patients (marginal human cases and animals) because moral agents have greater capabilities. Penguins can’t vote and vegans aren’t afraid to admit this. Why should we give welfare, roads and health care to animals when they don’t pay taxes? It isn’t speciesism to acknowledge factual differences between species, and this may entail giving a few more rights to humans than to rats.

However, babies and the severely intellectually impaired are at the same level of other animals, supposedly, just in human form. Granting more protections to them than we would to animals is speciesism, because there is no difference in cognitive ability and moral agency. Vegans don’t see the pernicious potential here because they generalize the rights we give to babies and the intellectually impaired: treat babies and animals as equals and both get to live. Yay!

But actually, human marginal cases get a little more than the libertarian right to be left alone. If for some reason their parents are unable to continue being parents, or their parents die, society will step in and take care of the orphaned or maltreated babies and intellectually impaired. It would seem most people believe society has an obligation to take care of humans who are absolutely incapable of taking care of themselves. Animal liberators free minks who then get run over or die from overheating, but it would be a crime to “liberate” a baby or mentally impaired person by leaving them to their own devices if their parents were gone or incompetent. This raises the question, then, of animals that are similarly unable to fend for themselves. Does human society have an obligation to take care of every animal that is as helpless as an orphaned baby?

And if not, how is that not speciesism?

One solution is to give babies and the intellectually impaired fewer rights. Would we be okay with sterilizing babies and the cognitively disabled? If so, fantastic, we can keep spaying and neutering animals so that they don’t overpopulate. But if we are not okay with removing the sexual organs of babies and the cognitively impaired, any human meddling with animal population control is out.

Is it fine to have adoption shelters for baby humans and then put the babies to sleep if no one adopts them in time? If so, that means we can keep dog and cat kill shelters. But if we can’t do that with babies (and many people would be uneasy with this idea), kill shelters for dogs and cats would have to go.

Most vegans might be okay with that at first glance, but this means humans would have a legal obligation to feed and shelter all helpless animals indefinitely. Seeing an abandoned baby bird and not attempting to save it would potentially be a crime. And if vegans faced that spaying and neutering animals is a violation of animal interests and goes against vegan principles, it would become much harder to control dog and cat populations, making this obligation even more difficult to fulfill.

There are farm sanctuaries for rescued cows and chickens and vegans are happy to run them. But these are small and rare, which is fine because currently there is no obligation to rescue and raise all animals that can’t take care of themselves. If there were such an obligation – and the Argument From Marginal Cases says there is if we take care of parentless babies and the intellectually impaired – we would need more sanctuaries and volunteers than we might be willing provide.

Also, it’s a bit unsettling to try to perfectly align the moral status of babies, the intellectually impaired and other animals. I’ve seen a lot of news stories about cops going to people’s houses and shooting the dog if it barks at them. It’s always disturbing to hear about this, but wouldn’t it be worse for a cop to break down someone’s door and shoot the baby for crying, or the developmentally delayed boy for yelling? According to The Argument From Marginal Cases… no it’s not. Shooting a baby is no worse than shooting a dog. Isn’t there something off about this?

The Argument from Marginal Cases is an appeal to consistency, but it is a consistency that no one wants to agree to once we look more closely at the rights that infants and the cognitively impaired have.

4) The Argument From Marginal Cases is based on a false premise; as animal rights professor Jean Kazez argues, sentience is not actually what we have on our minds when we don’t kill and eat babies and the intellectually impaired.

We used to not give the intellectually impaired rights. Is this because we were unaware of their sentience? When someone throws their baby in the trash can, is this because they are ignorant about the baby’s ability to feel pain, thinking that nerves develop later in life? If sentience were the thing that mattered to us, animals would already have their rights.

One concern with killing and eating babies might be that this would hurt the babies, but we don’t seem worried about causing babies pain when we circumcise them. The excuse “Oh, he won’t remember the pain!” after cutting off foreskins suggests that we aren’t opposed to inflicting pain per se, but pain that will traumatize rational beings. Anyway, if causing pain to sentient beings was what bothered us, we could figure out a way to kill babies painlessly. The real reason we don’t kill and eat babies is that this would subvert our rationale for having them: we want to head a family and for our children to grow up and replace us, keeping some semblance of our genes and values in the world after we die.

Some vegans say that it’s unfair to look at what babies are going to become as we assign rights; we should look at what babies are and not what they will be. If we took this “argument from potential” to its grim final conclusion, these vegans say, we could see babies as future dead adults. So if we can give babies more rights than animals because babies are going to grow up to be moral agents, we could also look a little further and see babies as corpses and based on that potential take away all their rights completely.

However, ignoring the potential that babies have to become grown-ups makes for a strained argument since the fact that babies grow up is precisely why we have them.

Say that most humans were born as fully formed moral agents and that babies as we now know them were an occasional breeding mishap. What would we do with babies if they did stay babies forever, never growing up? Would we avoid killing them because of their sentience? Or would we eventually grow tired of their screaming, hungry ways and find a convenient, “humane” method of disposal? My guess is the latter. Babyhood is a temporary state, and that’s what makes babies worth protecting.

On the other hand, severely mentally incapacitated humans could serve as a counter-example to that. Aren’t they just grown-up looking versions of forever babies? And don’t we protect them anyway? Arguably yes, but again, I am skeptical that sentience is the only or main factor here.

First I should say that I would not want to live if my brain were functioning at the level of a pig’s and had no hope of improving. I’ve often heard people say, “If I ever get to that state, please shoot me,” and though I wouldn’t shoot them if they were in that state (awkward), I would wish the same for myself. To me it doesn’t seem like a life worth living. The reasons that I enjoy life and want to live as long as possible would not exist for me in that condition. If I were about to be born and I was told there was some chance that I would be born as a severely intellectually impaired person who would never be capable of accomplishing more than a squirrel, and I had the choice of being killed immediately or living out that life, I would pick death. This seems like a contentious thing to say, but maybe it’s not.

Nevertheless, there is a reason to protect these lives, and I don’t think sentience is it.

Usually when people talk about extending lives that most of us wouldn’t want to live ourselves, the reason is to “protect human dignity.” There is something disturbing about lining up severely mentally impaired people and marching them to the hospital to be put to sleep, even if most of us would say, “If I’m ever in that condition, please march me to the hospital and put me to sleep.”

Killing humans who have lives that most of us don’t feel are worth living just looks too much like killing humans… which it is. There is a slippery slope fear here – how do we define extreme intellectual impairment and what if we start getting less choosy about it? – but there’s more to it than that. We brought the mentally impaired people into this world, and though some parents would say this means “we can take them out,” a more common feeling is that we can’t get rid of them just because they don’t have the features that we think makes human life worth experiencing. To a vegan this may sound like speciesism, but I think a fairer way to put it is that because humans created them, and they are from us in a sense even if we aren’t their parents, we feel responsible for them. Something being sentient does not in itself inspire that same sense of duty.

Also, protecting babies (even theoretical forever babies) and the intellectually impaired does not entail much loss other than convenience and money – though this can amount to a lot of lost convenience and money for families directly related to the intellectually impaired. This exchange may be worth it in order to tell ourselves that we are moral people who don’t do such a thing as kill humans for not being up to normal functioning human standards.

Everyone giving up all animal products to try to achieve a similar feeling is a much bigger sacrifice, and in my opinion, a terrible exchange.

5) Humans invent morality to improve life for humans, and obligatory animal rights as a consequence of following the Argument From Marginal Cases is a moral rule that does nothing but makes life worse for humans.

And why would we be so foolish as to concoct and obey a moral rule that only serves to make our lives worse?