Separating Humans from Animals

Preliminaries

Speciesism is predicated on the belief in a fundamental, morally-relevant difference between humans and other animals (in the same way racism, sexism, ableism, etc. are predicated on the belief in a fundamental, morally relevant difference between people of different races, genders, abilities, etc.). Like racism, sexism, etc., speciesism is not always manifested as conscious act by one individual targeting another. It can manifest as unconscious biases, or as problems with human-constructed systems which unfairly handle the interests of other animals.

Note that not all “-isms” are automatically bad. We could make up a term like “criminalism”¹ to refer to discriminatory behaviors/systems based on a belief in a fundamental, morally-relevant difference between people who have committed serious crimes (like murder, violent assault, etc.) and those who have not. We might say that systems like prison, which deprive people of freedom based on their status as criminals or non-criminals, are “criminalist”. But it’s not clear this is wrong. After all, most of us think there is a morally relevant difference between criminals and non-criminals: criminals have intentionally done things which have hurt other people and violated the rules constructed by our community. Don’t such people deserve to be treated differently? It’s not clear, however, that this difference between criminals and non-criminals is fundamental. Some people still oppose criminalism on the basis that many “criminals” are victims of circumstance (like those forced into a gang to survive) rather than because of any fundamental immortality or evil inside that person. However, a case needs to be made: what of the individual responsibility of those people? At least it’s not obvious that criminalism is a bad thing in the same way it is obvious to us that racism and sexism are bad.

Keep in mind, the question we are trying to answer is not:

“Is speciesism a real thing?”

it’s:

“Is speciesism (as we commonly practice it) OK?”

Speciesism is undoubtedly real: if you slaughtered, butchered, and ate a dog or cat as is routinely done to pigs, you would go to jail in many states. This differential treatment based on the species of the victim is explicitly encoded into our laws, with dogs and cats being afforded special protections that farmed animals are not.

Also, keep in mind that just because you oppose the more extreme forms of speciesism (like bull-fighting being a legitimate sport) does not necessarily mean you don’t support (either implicitly or explicitly) other forms of speciesism which may also be harmful. Remember, you don’t need to be lynching black people to be racist, and you don’t need to be campaigning to legalize wife-beating to be a sexist. There are plenty of more subtle ways of being racist, sexist, or speciesist. So perhaps a clearer way of phrasing our question is as follows:

“Are the forms speciesism which you commonly support (implicitly or explicitly) morally OK?”

Of course, this depends on what forms of speciesism you support. We’ll try to target this towards the typical “ethical omnivore”. This would be someone who, perhaps, buys only organic produce, local if possible; who buys meat and dairy only from Whole Foods with labels like “certified humane”, or from expensive restaurants, or a local butcher shop, charcuterie, fromagerie, etc.; who makes some effort to avoid products which cause excessive environmental destruction; tries to reduce their meat and diary consumption compared to a typical American; etc. We’ll assume you don’t explicitly support factory farming, flagrant animal abuse, bull-fighting, dog-fighting, unnecessary experimentation on intelligent animals like chimpanzees or dolphins, or meat products like foie gras and white veal. But you know what we’re not going to assume? We’re not going to assume you don’t implicitly support a bunch of really harmful speciesism. Because in all likelihood, you do (even if you don’t realize it).

The approach we are going to take to answer our question is to explore whether there are any fundamental, morally-relevant distinctions between humans and other animals which might justify the kind of speciesism we see in our society. Some proposed traits by which we may be able to distinguish humans from animals in such a way include:

• intelligence
• linguistic capacity
• self-awareness
• possession of advanced culture
• the ability to plan for the future
• possession of a soul / spirit
• ability to make laws and develop moral frameworks
• and many more …

There are a few ways of dismissing such a trait:

1. We can argue that the trait does not pick out something fundamental to humans and only humans. We would establish that this trait doesn’t really separate humans from animals because it is either not possessed by all humans we think deserve protection, or it is possessed by many non-human animals to whom we deny that protection.
2. We can argue that the trait is not morally relevant. These are things like skin color, XX vs XY chromosomes, socially constructed traits like citizenship, etc. which should not, in themselves, morally justify an individual being exploited or harmed.

It is of course easier to dismiss a trait by method (1) than method (2): for method (1), we only need to provide scientific evidence. For method (2), we also need delve into ethical principles. Since everyone and their grandmother has their own theory of ethics which permits all the things they personally like and forbids all the things they don’t like (think about all those people following the bible when it comes to being anti-homosexuality, but disobeying it when it comes to welcoming immigrants), this is a difficult task. Method (2) is difficult even when trying to rigorously argue against the holocaust, so try to be charitable and not just ad hoc come up with a new ethical theory every time to avoid each new problem we raise in our method (2) arguments. Here’s an example of such bad flawed ad hoc reasoning to avoid:

Slippery Obtuse Person: “Humans are better than other animals because we have opposable thumbs and they don’t”

Me: “Some people are born without thumbs or hands at all, and we do not think we should treat them worse because of it. Some frogs have opposable thumbs, but we do not treat them better. Shouldn’t our ethics care more what is going on inside their head than the shape of their body?”

Slippery Obtuse Person: “Well, this is irrelevant, because God gave humans dominion over other animals, and that’s all that really matters when it comes to ethics”

Don’t be like Slippery Obtuse Person. If you hold your position based on a particular ethical framework, don’t switch it out and argue on the basis of a completely different ethical framework just because your reasoning was challenged. That being said, let’s proceed.

Proposed Trait: Humans were created with souls, but animals weren’t. Humans aren’t animals.

Humans are animals, and this has been established by over a century of scientific work, starting with Darwin, and elaborated upon and confirmed by thousands of other scientists. All scientific evidence points to the fact that there is no sharp line between humans and other animals (be it presence/absence of an immortal soul, or any other radical difference in kind), because there is a continuous web of ancestry linking modern day humans to other primates, to other mammals, etc. In addition, the bible itself has passages critical of the idea that there is some fundamental distinction between the souls of humans and other animals:

“For what happens to the children of man and what happens to the beasts is the same; as one dies, so dies the other. They all have the same breath, and man has no advantage over the beasts, for all is vanity. All go to one place. All are from the dust, and to dust all return. Who knows whether the spirit of man goes upward and the spirit of the beast goes down into the earth?”

– Ecclesiastes 3:19

Proposed Trait: Humans have the capacity for language.

#NotAllHumans

Some people are born with or sustain damage to small regions of the brain known as Broca’s and Wernicke’s areas, which render them unable to speak or otherwise process language as most other humans can. Such people can often still demonstrate their cognitive faculties in other ways, and most doctors would not advocate forcibly impregnating these people, killing them at a young age, performing non-consensual experiments on them, or any of the other practices we commonly do to animals with a similar level of linguistic ability.

Some people with severe autism are completely non-verbal all through childhood. Some gain their ability to speak/communicate only through technology or much later in life, and some never do. No one advocates that these children be classified as property, as farmed animals with similar levels of verbal ability are.

While linguistic ability is essential for certain kinds of complex tasks we value as humans, there is no scientific reason to suggest that lack of linguistic ability makes sharp metal clippers or burning irons and other such things feel less painful on the flesh. So this is not a good reason to perform procedures on animals like branding, tail-docking, de-beaking, tooth-clipping without anesthetic as we do on farmed animals. There is no scientific evidence suggesting that a lack of linguistic ability prevents someone from suffering from sexual victimization through forced insemination and child separation.

The idea that animals suffer less from these things than humans is often assumed, but where is the scientific evidence in support of this? If anything, lack of linguistic abilities prevents animals from expressing to us their internal experiences, making it harder for us to judge when they are suffering in serious ways. It is this reason why non-verbal people with disabilities face high rates of victimization: they cannot effectively communicate to others how they are being victimized. Mother cows are known to yell for days after their calf is taken away (it is a distinctive sound). Is it fair to paint this as “just instinctual” because she cannot express her thoughts in English to us?

But there are even more problems with this viewpoint (that linguistic abilities are all that matter). It is known that Neanderthals existed at the same time as humans, and had a similar level of technology to humans. They held funerals with flowers, made stone tools, etc. They even had larger brains than us. But they did not have (according to Noam Chomsky, among others) the capacity for language with a generative grammar like we do. In other words, they might have had a finite number vocal signals like many other animals, but no ability to express complex thoughts through sentences constructed via grammatical rules. In fact, our ancestors as recent as 50,000-100,000 years ago may not have possessed this ability. This is incredibly short on an evolutionary time scale. For this reason it is overwhelmingly likely that the rest of our brains (dealing with, say, emotion, spacial perception, social relationships, etc.) have not drifted significantly from those of Neanderthals or of our ancestors 100,000 years ago who did not possess our capacity for language. Given this, it is reasonable to assume that the experience of living as a Neanderthal or as a human 100,000 years ago, would have been substantially similar to that of the experience of being a modern day human in many respects. If Neanderthals or our ancestors of 100,000 years ago had survived to the present, would we feel justified in exploiting them, enslaving them, doing live experiments on them, etc. because they lack the capacity to learn English or German? Most people would likely be opposed to this, because we recognize that lacking this particular cognitive ability (language) would not thereby remove our ability to suffer from pain, emotional loss, etc.

Physiologically, the parts of our brain that deal with things that hurt us the most deeply, like raw physical pain, emotional pain, fear, etc. are very old evolutionarily, existing also in the brains of cows, mice, and many other animals. It is true that a human can suffer in more nuanced ways because of language. For example, a human might suffer because someone tells them, “Your friend Zhou, he died last night”, where as Zhou’s dog would not react to this same sentence. But neither would someone who doesn’t speak English. Pigs, cows, chickens, and rats have all been proven (using brain scanning) to have an emotional reaction to others dying or being harmed. The fact that they cannot find out about the death of another through a verbal utterance does not mean they cannot suffer from such a loss.

Proposed Trait: Humans are self-aware, while animals are not.

The standard test for self-awareness is the “mirror test”. In the mirror test, a colored dot is placed on an individual that they cannot sense directly. The individual is then placed in front of a mirror. If they try to remove the dot on their own body after seeing their image in the mirror, this indicates they have recognized the figure in the mirror with the dot as themself (rather than someone else who looks like them), and thus they must have an awareness of themself. There are a few standard ways to control this experiment:

• Test a control group with a colored dot made of the same material as in the experimental group, but which matches the color of their skin (e.g., a black dot on a crow, or a grey dot on a dolphin). We should expect the control group to not react (since they shouldn’t see it). If they do react, then they may be detecting the dot by other means, such as smell, touch, etc. When doing this control, adjustments need to be made for the visual systems of other animals: some colors indistinguishable by humans are distinguishable by other animals and vice versa.

• Test a control group in front of a piece of transparent glass with other individuals of the same species on the other side who have dots on them. It may be that the reaction of trying to remove/scratch the dot on themself is a sympathetic reaction to seeing others with a dot, in the same way people often sympathetically laugh without actually understanding the joke, or sympathetically feel like vomiting when they see someone else eat something gross. If the control group still tries to remove the dot, the experiment needs to be refined to eliminate the possibility of it being a sympathetic reaction.

The important thing to keep in mind here, however, is that while passing the mirror test is typically considered good evidence for self-awareness, failing it is not good evidence against self-awareness. For example, blind humans will fail the mirror test. Dogs fail the mirror test, and it is suspected (but not proven) that they fail because scent, not sight, is their primary means of recognizing each other. Dogs do pass the “sniff test of self-recognition”, which is evidence in favor of this theory. Other animals may fail because they are simply not interested. In general, it is important to try to be aware of and try to correct human-centric bias when designing tests of animal cognition, just as it is important to be aware of and try to correct cultural bias when designing tests of human cognition (e.g., being aware of the cultural bias in test questions like “Marathon is to Runner as Regatta is to _____________”).

With this caveat, here are the animals who have passed the mirror test, with controls in place:

• Tursiops truncatus (bottlenose dolphin)
• Orcinus orca (killer whale)
• Pan paniscus (bonobo)
• Pongo pygmaeus (Bornean orangutan)
• Pan troglodytes (chimpanzee)
• Homo sapiens (human being)
• Elephas maximus (Asian elephant)
• Pica pica (Eurasian magpie)
• Myrmica sabuleti, Myrmica rubra and Myrmica ruginodis (species of ants)
• Labroides dimidiatus (cleaner wrasse, a tiny fish)

Notice that not only does this list include non-humans, like chimpanzees and bonobos (who are commonly tested on in laboratories, including lethal experiments), it also includes non-primates, like whales and dolphins. And not only does it include non-mammals, it includes non-mammals, like the magpie (bird) and cleaner wrasse (fish). And not only does it include non-mammals, it also includes non-vertebrates, like those species of ants. Here’s a summary of this study on ants (from wikipedia):

In a Belgian study from 2015, 23 out of 24 adult ants scratched at small blue dots painted on their clypeus (part of their “face”) when they were able to see the dot in a mirror. According to the published results, the ants were individually tested and were from three species, Myrmica sabuleti, Myrmica rubra and Myrmica ruginodis. None of the ants scratched the clypeus when they had no mirror to see the dot. None tried to scratch the blue dot on the mirror. When they had a mirror and a brown dot similar to their own color, only one of thirty ants scratched the brown dot; researchers said she was darker than average so the dot was visible. They also reacted to the mirror itself. Even without dots, 30 out of 30 ants touched the mirror with legs, antennae and mouths, while 0 of 30 ants touched a clear glass divider, with ants on the other side. Ants a few days old did not react to the dots.

You can read more about the controls in the study itself.

The important thing here is not so much who is on (or isn’t on) this list. It’s the immense diversity of animals on the list. We have both large-brained animals like chimpanzees who are incredibly close to us genetically, as well tiny fish like the cleaner wrasse and ants, who diverged from us evolutionarily more than half a billion years ago. What this all suggests is that there is nothing special about humans in possessing self-awareness. It is certainly not a trait which evolved only in modern humans, or only in animals very close to humans. It is still an open question why so many other animals fail, but at the very least self-awareness does not appear to be a good way to separate humans from other animals.

Now, at this point you could update your ethical beliefs by saying “Fine, I won’t exploit/kill/eat/test on chimpanzees, dolphins, cleaner wrasse, those three species of ant, Eurasian magpies, whales, etc. or anyone else who passes the mirror test. But chickens, cows, and pigs aren’t on that list, why should I feel guilty eating them?” In other words, you update your “line of discrimination” from one with humans on one side (or perhaps humans and a few “smart” animals like elephants and dolphins) versus all other animals on the other side. You move a few animals from one side of the line to the other (sacrificing the ability to exploit animals you really had no desire to exploit in the first place), and now you can still consistently exploit chickens, pigs, and cows for the things their bodies produce, right? But is this really an honest ideological tactic? I bet you weren’t going to classify ants and those tiny fish as animals deserving of protection before now, so this would certainly be a major shift in your attitude towards those animals, all to maintain self-awareness as the “gold-standard”.

But even if you update your ethical beliefs in this way, you’re still totally fucked. Not all humans pass the mirror test. In fact, humans only start passing the mirror test around 18 months of age, so you better start cracking those toddler skulls for your next potluck if you want to stay ethically consistent here.

Proposed Trait: Possession of Advanced Culture

Ah, you must be British. This wonderful excuse was used by the British to justify subjugating indigenous people around the world. There were actually legal proceedings where the British debated whether what they were doing to the Australian aboriginals was OK, seeing as it would violate the international laws they had been expounding elsewhere. What was their ruling? That these international laws only apply to “civilized” people.

Humans certainly have been capable of great accomplishment through culture, building on the knowledge of the past to reach new heights. But that doesn’t necessarily mean each individual in an “advanced culture” is worth more than that of an individual living closer to nature. In fact, the average person in an “advanced culture” is often missing skills that people living closer to nature would consider basic. You mean you can’t identify any of the wild edible plants here? You don’t know which water sources are clean? You don’t know how to find shelter?

And keep in mind, the “rights/privileges” we’re talking about granting these individuals who do not have advanced culture are not things like the ability to ride in our rocket ships and use our computers (the products of our advanced culture). They are basic rights like the right to bodily autonomy, the right to not be killed arbitrarily, the ability to raise their own offspring without them being taken away arbitrarily, etc.

Why should we think that the culture we are part of has any relevance to our moral status at all? You might try to make arguments like, “only those whose ancestors did the hard work of developing a justice system with due process deserve to benefit from it”. But then you are basically arguing against natural rights. You can do it, but do you want to? You’d be adopting a play right out of the fascist handbook (“it is the state/ancestry that gives you rights!”)

Alternatively, you might say that it is not about what culture you are a part of per se, but rather your capacity for developing an advanced culture (whether or not you get the opportunity to be in one). In other words, even if you are living alone in the middle of the woods, you still have the innate capacity to play a crucial role in developing a complex, lasting, constantly-improving culture (you are just not realizing it). A cow doesn’t have this capacity: they wouldn’t be able, perhaps even in principle, to develop tools to build tools, pass down knowledge indefinitely through the generations, etc. If that is your argument, then I hope you enjoy the leg-of-person-with-mental-disabilities I have prepared. Don’t worry, this person would never have been able to invent the printing press, or representative democracy.

But wait a minute, it turns out after all that we don’t eat human beings who are unable to contribute to advancement of our culture (due to mental disability or other reasons). We also don’t force them work as slaves, do live experimentation on them, sexually exploit them, allow them to be bought and sold, or anything of the sort (well, sometimes we do, but most of us agree that we shouldn’t). On the other hand, we do often deprive people with mental disabilities of the ability to enter into contracts, to vote, to make their own medical decisions, etc. The rationale here is that such a person would not benefit from these rights (in fact, they may even open themselves up to exploitation if they were granted some of these rights). I’ll be upfront with you: I don’t care if you deprive cows or pigs or chickens of the right to vote or enter into contracts. But I do care if you try make this argument that depriving cows, pigs, and chickens of basic rights is OK because they can’t develop an advanced culture like ours, while granting these rights freely to humans who are equally incapable of building an advanced culture such as ours.

At this point, many people change course: maybe it’s OK to buy and sell mentally disabled people, to sexually exploit them, etc. as long as they “don’t really understand what is happening to them” and “steps are taken to avoid them feeling physical pain”. Maybe we just don’t do these things because they look bad, but in principle there is nothing wrong with them. I’ll start off by saying that if this is the approach you are taking, you really might want to consider why you are being so stubborn on this “it’s my right to exploit other animals as a human” thing. Is the benefit really so great to being able participate in this exploitation? Wouldn’t you feel better about yourself as a human being if you abstained from it? But let’s put that aside and continue by addressing this line of reasoning. First of all, exploitation has a nasty habit of making its mark on someone, even when the exploiters are trying to make things “as comfortable as possible” for the individual being exploited. Mentally disabled people are often sexually abused, because they make easy victims. Their exploiters try to justify their actions with exactly the kind of reasoning you are making. The fact of the matter is that even severely mentally disabled people can be hurt greatly even by exploitation they barely understand. They way people are typically hurt through exploitation is not usually through actions committed by the exploiter with the intention of causing harm to the exploited. Rather, it is from incidental harms that happen to the exploited due to the carelessness or apathy of the exploiter as they obtain what they want from the exploited. This is not some wild theory. It applies to pretty much every form of exploitation. It applies to the bosses at the Triangle Shirtwaist Factory who locked the doors so their employees couldn’t take extended breaks, and thus led to their gruesome deaths when the factory caught fire. It applies to British colonial exploitation of most of the world. It’s not like those factory bosses or British colonialists were thinking, “Let’s go make a bunch of people miserable”. Quite the contrary, the British liked to think of themselves as civilizing, as spreading justice throughout the world. The British built massive infrastructure projects, ostensibly helping the people they were colonizing. But the interests of the exploiters take precedence over the interests of those being exploited, and when there is a conflict between these two, the exploiter will usually win out, and they will sometimes win out even when the harm caused to the exploited is disproportionately large with respect to the benefit to the exploiter. It is irrelevant whether the exploited understands that or exactly how they are being exploited. The problem is fundamental to the arrangement: the interests of the exploited are not being adequately represented. The interests of the exploited are respected only so far as the exploiter’s good will extends.

Proposed Trait: The Ability to Plan for the Future

A genus of spider, Portia, has been proven to plan for the future. They mentally model long, complex routes (which may take hours to traverse) while hunting to avoid bad situations (like being stuck in water, or visible to their prey). They are by no means unique: many animals are capable of planning for the future.

Proposed Trait: The Ability to Form Long-term Memories

Goldfish have memories longer than three seconds. They have pretty vibrant long-term memories, allowing them to remember how to solve puzzles they have seen before, even many months ago (it is likely years, but current studies only tested a time frame of months). The fact that this myth even existed and spread in the first place shows how absolutely abysmal the general public’s understanding of the cognition of other animals is.

If anything, other animals tend to have more limited “short-term” or “working” memory: this is the amount of information you can keep in your head at once (be it experiences, prior thoughts, etc.). But this is not universally true. Humans are actually beat by chimpanzees handily in tests of numerical working memory (the ability to keep long sequences of digits, like phone numbers, in your head). This is work done by Tetsuro Matsuzawa at the University of Kyoto. The absolute mental superiority of humans over other animals has been unequivocally refuted. We could, of course, try to select a more limited collection of mental tasks which humans tend to win at, but this is rigging the game (more than we already are by designing the tests ourselves).

Proposed Trait: Ability to Make Laws and Develop Moral Frameworks

Our response here is pretty much the same as for the “possesses an advanced culture” trait. Just because you don’t have the capacity to write laws or books about moral theory doesn’t mean you don’t deserve to be protected from harm.

Proposed Trait: Intelligence

Chimpanzees outperform humans in numerical working memory tests. Bats can perceive complex shapes through sound in a way humans cannot: our brains simply lack the appropriate wiring to do this complex cognitive task (our ears are just fine). Woodpeckers outperform all but the most mathematically trained humans in certain kinds of statistical decision making. Pigeons can outperform humans at fast-paced multi-tasking. Rats outperform humans in what are known as “implicit category-based generalization tasks”. To the question, “do humans perform better at mental tasks than animals?”, the correct response is, “which mental task, and which animal?”, because it really does depend.

Of course, you can respond, “Well, I’m not talking about specific intelligences, I’m talking about general intelligence, like the thing IQ tests measure”. But this is a kind of nebulous notion. If you look into the definition of IQ, it is defined to be an abstract variable which is correlated most with (i.e. which best explains) all the other measures of intellectual ability we care about (e.g. scores on verbal tests, school grades, etc.). A general theorem in statistics guarantees the existence of such a thing. That same theorem in statistics also guarantees the existence of a single abstract variable which is correlated most with (i.e., best explains) dick size, best score on guitar hero, and colon length. Ultimately, since we are the ones choosing which quantities are measures of “intelligence” (things like the ability to answer reading comprehension questions, logic puzzles, etc.), we are the ones giving meaning to “IQ”. It is not a natural, objective measure of some kind of “general intelligence” the way people like to portray it.

But putting al this stuff aside about IQ, intelligence simply does not make an individual more deserving protection. We should not mourn the holocaust victims because some of them were really smart and might have solved difficult problems for us if the Nazis hadn’t murdered them. We should be mourning all of them, because they were killed unjustly and cruelly. We should be mourning both the geniuses, and the mentally disabled who were mercilessly slaughtered there. If the Nazis has only killed “stupid” people (say people scoring below 80 on an IQ test), would we really be OK with it? What if it was 70 instead of 80? At what point do you say, “Well, this individual is just too stupid to matter.” Is there really an ethical answer to this besides, “Never”?

See also our response to the “possesses an advanced culture” trait proposal.

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1. In fact, this already has a conflicting definition as a synonym for “criminalness”, but let’s ignore this for the sake of discussion.↩