N.B. For clarity, text that represents an argument put forward by an ideological opponent (not representing my own views) will be colored purple rather than black.
Arguments from a sense of paternalism and from humankind’s supremacy over other animals are pretty common tactics used to defend against the claim that we should give farmed animals rights (e.g. the rights to life and liberty). The argument from supremacy goes like this: humans are simply better than other animals, they’re smarter, more capable, and have earned in a life-and-death evolutionary struggle their right to be at the top of the food chain. Essentially, if another species like lions had beat humans out in the race to high intelligence, they wouldn’t hesitate to eat us, so why should we hesitate to eat animals we are clearly superior to? The argument from paternalism goes like this: we give farmed animals like cows, pigs, and chickens a much better life than they would have in the wild, protecting them from natural predators, feeding them, caring for them, etc., and so even though we eat a certain percentage of them from time to time, we are still treating them better than nature would. We brought these animals into what might be considered the height of their existence by offering them shelter from the brutal hand of nature, letting their populations grow much larger than they have ever been in natural history, and part of that bargain is that they’ll end up on our dinner plate. Which would you rather be, honestly, a chicken in the woods constantly worrying about being dismembered alive by foxes and struggling to find food, or safe in a fenced-off area with plentiful food with the caveat that you die a quick and relatively painless death when you get old?
Let’s start by recognizing some initial concerns with the argument from supremacy. Even people who oppose strong animal rights probably hesitate a bit to endorse the argument from humankind’s supremacy. It seems to be reminiscent of “might makes right” mantra of Social Darwinism, which in the past justified unconstrained conquest and domination of other human beings. Humans are not exactly living in nature anymore, so we ought to hesitate before modeling our code of ethical behavior on the brutality that we see in nature. Those who do ultimately do take up this argument from supremacy can defend against the comparison to Social Darwinism as follows. Humans all over the world are substantially similar to each other, and the differences in power between different people are usually due to accidents of history, not any intrinsic biological superiority of the people of one country or social class or race or gender over another. There is no innate biological advantage to being a white male, just a social advantage arising from a complex history of oppression, which we ought to condemn. In contrast, there are real, substantial biological differences between humans and other animals. Compared to the animals we eat, humans have many more neurons, a far more developed cortex, and the rare capacities for language with a generative grammar, written culture, formalized logical reasoning, and many other impressive capacities which ought to grant them a special status and moral consideration. In short, Human Supremacists can distinguish themselves from Social Darwinists (such as White Supremacists and Nazis) by noting that Social Darwinists base their theories of supremacy on unscientific bullshit, while Human Supremacists base their theory of supremacy on scientifically verifiable facts about the capacities of humans compared to other animals.
We should also recognize some initial concerns with the argument from paternalism. The argument from paternalism seems to be based on a wildly inaccurate picture of our relationship with animals. The vast majority of farmed animals are raised in factory farms with abhorrent conditions, have been selectively bred to overproduce meat, eggs, or milk, are slaughtered at a fifth of their natural life span, have lost reproductive autonomy, rarely get to see their offspring, if at all. Broiler chickens, for example, have been bred to grow so quickly that once they reach what would normally be adolescence, they are too heavy for their own legs to support them. Egg-laying chickens produce around an egg a day (their ancestors laid around an egg a month) which causes severe health problems due to leeching of calcium from their bones, among other things. Even if it is possible to justify eating an animal who has lived a long and happy life in old age, this simply isn’t what happens to 99.9% of farm animals. And there are strong economic reasons why this isn’t the case: the cost of animal products coming from animals allowed to live a full and natural life would be prohibitively expensive for most people, and farms which try to give animals even moderately better lives tend to find themselves out-competed in a free market by farms which instead devote their resources to making end consumers falsely believe their animals are treated well. Paternalism may be a good way to justify our relationship with dogs and cats, who we welcome into our homes and care for when they are sick, even at great expense. Most dogs or cats do not understand why we take them to the vet, but we take them there anyway for the same reason we give our toddlers shots, even when they explicitly don’t consent: we know better, and we are doing what is in their best interest. If they were able to understand why we are doing these things, they would certainly approve. But Paternalists would be hard pressed to say the same is true for farmed animals. Would farmed animals really consent to what we are doing if they had the capacity to understand our reasons? It certainly feels like with farmed animals, our intention is not primarily to give them a good life, but to exploit the resources they provide us with. At the very least, a recognition of how Paternalism has been used to justify “enlightening the savages” and keeping women in the home should give us pause. We should be asking ourselves, are we making a similar mistake people have made in the past, blindly putting our own desires ahead of those we are supposedly benefactors to? However, Paternalists can argue that while it is true that most farmed animals are not cared for in the way they should be, it is still possible in principle to treat farmed animals with respect and decency without granting them rights. Paternalists could argue that our relationship with farmed animals today is similar to our relationship with child workers during the start of the industrial revolution: we are over-exploiting them, but it doesn’t have to be that way. Paternalists might oppose factory farming (as well as child labor in factories), while still denying rights to animals (or children) that we give to adult humans. They might look to ancient instances of shepherding as positive examples to aspire to in our relationship with animals. To sum up: sure, we treat animals horrible now and in a non-paternalistic way, but that doesn’t mean that a form of paternalism towards animals couldn’t be an acceptable alternative to granting animals rights.
Before we delve further into these issues, we should try to understand at least one line of reasoning giving justification for animal rights. Although we might see issues with Human Supremacy and Paternalism, that does not automatically translate into a positive justification for granting animals rights. Rights are an incredibly subtle and complex topic, and there are hang-ups that can confuse advocacy for rights. The main hang-up we should address is that rights are largely a human construction, as are all explicit ethical codes. The Bill of Rights was written by fallible humans, using pen and paper. This is so even for human rights that we consider basic, such as the right to free expression. It’s worth noting that there was sufficient debate about the centrality of this right at the time that it was not placed in the U.S. Constitution itself (where the rights to life, liberty, and the pursuit of happiness are prescribed), but only as an amendment. The Supreme Court of the United States of America still regularly makes new rulings on where, exactly, the limits of right to free expression lie. Even for ancient ethical codes such as the Ten Commandments (which one could argue are a philosophical precursor of rights), you won’t ever discover them by looking at the structure of DNA or by performing sophisticated experiments. Ethical codes simply don’t have an objective existence in the same way that rocks and trees do. They arise from a complicated mix of thoughts in our brains and dialogue and tradition. However (and this is the important point) this does not mean that we should take an “anything goes” attitude towards ethics. We can recognize that the entire body of legal doctrine, from building regulations to the right to a trial by a jury of your peers, was thought up and written down by people over hundreds/thousands of years, while still recognizing that there is a logic, reason, and sensibility behind all of it which is important to preserve, even as we change the letter of the law. So as we make our ethical considerations, we want to be asking ourselves questions like, “Does this fit with the framework of ethics as I understand it? Are these two principles incongruous? Is this coherent, or arbitrary? How would I feel about these principles if I were someone else?” These sorts of questions can be fruitful. However, we probably shouldn’t (at least right now) entertain arguments about ethical nihilism, such as “Do rights really exist? Why not just act in a way that makes us feel good?” etc. Why not? Because discussions of ethical nihilism are really out of place in a discussion like this. Imagine starting a discussion in the UN about what constitutes ethical treatment of prisoners of war with, “Well, why should we hold ethical principles in the first place?” These discussions certainly have their place in a philosophy course on the foundations of ethics, but it is strange to let these concerns selectively derail discussions about serious issues like animal rights which affects trillions of sentient beings, while miraculously having no such concerns about the foundations of ethics when it comes to your sense of indignance at a neighbor parking where they shouldn’t or saying something mean to you.
This argument for animal rights is going to be crude, and intentionally so. The reason for making a crude argument instead of a refined argument is that we don’t want to get into the weeds too much either in the theory of rights, nor in the specifics of animal sentience, both of which are intimidating topics to do justice to. This argument is more a rough first-pass which is good enough to illustrate our point. The basic idea is we are going to estimate the amount of “mind stuff” which belongs to humans versus animals. We propose a simple ethical principle: any two equal amounts of mind stuff deserve equal moral consideration. When it comes to humans, we expect that most of them have roughly the same amount of mind stuff, so as a consequence all humans deserve equal rights. We’ll try to justify this ethical principle later, but for now let’s just try to figure out a proxy measure for “mind stuff”. A proxy measure is used when it is basically impossible to measure something directly. For example, if a farmer wants to estimate how many grains of wheat they produced in a year, they might weigh their total production, count how many grains are in 100g of wheat, and multiply these together to get a proxy measure for the total number of grains. Since we expect the number of grains to be roughly proportional to the total mass, this gives a reasonable estimate. And it’s much more practical than counting out millions of wheat grains by hand. It’s not guaranteed to be precise, but for a crude estimate, it works just fine. The reason we need to use a proxy measure here is that there is no way to actually measure something like “the amount of mind” something has. Philosophers of mind don’t even have a definitive way of empirically determining whether other human beings are even conscious (see the Wikipedia Article on Philosophical Zombies for more background). So we need something that we can reasonably expect to be correlated with what we’re calling “mind stuff”. The proxy measure for “mind stuff” we are going to use is pretty crude: number of neurons. A honeybee has four times as many neurons as an ant, so we estimate a honeybee has four times as much mind stuff. Now we need to make a heuristic argument why this estimate isn’t so bad.
First of all, we expect ten humans to have around ten times as much mind stuff together as one human. And we also expect ten humans to have ten times as many neurons together as one human. Furthermore, by analogy to multicore processors, doubling the number of transistors should roughly double the amount of computing power, so doubling the number of neurons should roughly double the amount of mental processing going on. I can already hear the objections coming in. Let’s tackle some of them:
Objection 1: Some arrangements of neurons are more important to a mind than others. For example, we expect perhaps that neurons in the cerebral cortex are more important when it comes to the human mind than neurons in the brain stem, because they are associated with more complex thought. Of course a person needs a brain stem to live, but perhaps it’s reasonable to suspect that the human mind, as we know it, is mostly located in the cerebral cortex. And how do we know that some animals with relatively large numbers of neurons aren’t just wasting their potential by having them arranged in a sub-optimal way which doesn’t bring about very much mental ability at all?
Response to Objection 1: Evolution is pretty good about not wasting resources. Animals like the sloth, which need to live off of very little energy, have evolved small brains relative to their body size. It’s simply too expensive to keep neurons around which aren’t doing anything important for survival. For this reason, it would be surprising if large swaths of neurons in the brain of an animal were to be useless to the mind of that animal. We don’t really know how neurons make minds precisely, but it would be unreasonable to suppose that nature created a bunch of brains that don’t do much. Furthermore, it’s not really true that the human mind is located in the cerebral cortex. For example, consider the following quote from neuroscientists Jeremy Schmahmann and David Caplan:
“The traditional teaching that the cerebellum is purely a motor control device no longer appears valid, if, indeed, ever it was. There is increasing recognition that the cerebellum contributes to cognitive processing and emotional control in addition to its role in motor coordination.”
“Cognition, emotion and the cerebellum”, https://academic.oup.com/brain/article/129/2/290/292272
Objection 2: Isn’t the number of neural connections in the brain, rather than the number of neurons, a better proxy for how much mind a brain has? If you double the number of neurons in a brain, all else being equal, the number of connections more than doubles.
Response to Objection 2: We aren’t aiming to be perfect. The reason for choosing number of neurons is that some neuroscientists believe that thoughts are associated with activation patterns in the brain (i.e., which neurons are firing, and how they are firing). At any one moment in time, it would seem heuristically the complexity of this activation pattern, in terms of the number of bits required to describe it, is limited more by the number of neurons than the number of connections between neurons.
Objection 3: I heard that brain to body ratio was a better proxy for intelligence.
Response to Objection 3: We are not measuring intelligence, which is typically measured by the ability to solve problems / puzzles. Hypothetically, someone could be capable of having amazing internal mental experiences while being horrible at passing IQ tests.
We could go into more depth here, but this would require delving into more neuroscience, and it seems like our time is better spent finishing this crude argument, especially since we are not aiming to give a perfect proxy, just something to guide our intuition.
Given our proxy measurement, we can now estimate the amount of “mind stuff” various animals have. The following table gives then neuronal count in the brains of various animals.
| ANIMAL | NUMBER OF NEURONS | |
| Elephant | 257000 Million | |
| Human | 86000 Million | |
| Gorilla | 33000 Million | |
| Brown Bear | 9600 Million | |
| Domestic Pig | 2200 Million | |
| Red Jungle Fowl (Ancestor of Domestic Chickens) | 315 Million | |
| House Cat | 250 Million | |
| House Mouse | 71 Million | |
| Honey Bee | 1 Million |
You may be surprised by some of the numbers here. For example, it appears as though elephants have roughly three times as many neurons as humans (and thus three times as much mind stuff, according to our proxy measure). We don’t have data for the number of neurons in a domestic chicken, but it appears that their wild ancestor has slightly more mind stuff as a house cat, so it stands to reasons domestic chickens likely have a comparable amount of mind stuff to house cats. Part of the reason these facts are counter-intuitive is because we see animals through a particular human-centric lens. We cannot communicate verbally with elephants, so it is hard for us to gauge the depth of their internal mental lives. Careful research into elephants has demonstrated that they hold funerals for their dead, engage in tool use, and engage in many other practices which were previously considered to be unique to humans. When it comes to cats compared to chickens, cats have been domesticated (that is, genetically selected) to interact with humans in ways that are engaging to us. For example, recent research has shown that cats only “meow” to humans: this specific communication method evolved specifically due to their domestication and integration into human societies. The path of domestication for chickens was quite different, so they have not had a chance to evolve any kind of special dialogue with humans. This makes it harder to us to recognize the depth of their minds. In addition, birds like chickens diverged from mammals a long time ago evolutionary speaking, so our brains don’t have as much in common as the brains of two mammals do. This makes it harder to humans to understand when chickens try to communicate compared to when mammals like mice or cats try to communicate.