Do animals experience pain? Do animals suffer?
With human neuroscience still in its infancy as a discipline, animal neuroscience is even farther behind. I am usually reluctant to loudthink about either subject, because I assume that what I say will be proven wrong in a few decades, if not tomorrow. Not much in-depth research has been done on animal cognition and emotion yet, and the difficulty of studying the subject doesn’t offer much hope for some breakthrough into the animal mind. Based on what little we do know—science that is decades old—I believe we can answer both questions, not with “definitive” answers, but with reasonable inferences for the time being that can guide our actions and activate our morality.
I divide these questions because there are semantic and psychological differences between pain and suffering. One is considered a physical sensation, the other an emotional experience related to the pain—a psychological state that results from pain and is more existential than pain. The distinction shouldn’t matter, but unfortunately it does, because some people argue that inflicting pain on animals isn’t exactly the same as inflicting pain on humans. Other people, far more clearheadedly, argue that inflicting pain on animals is exactly the same as doing so on humans. By the end of this essay, I am going to float the idea that cruelty to animals is actually worse than cruelty to (adult) humans; that it is the moral equivalent to cruelty to human infants. That is why I will handle these questions separately.
“Do animals experience pain?” is the easier question of the two; decades of Pavlovian experiments have shown that animals will stop pressing a button or pulling a lever if it results in their getting zapped. They remember the pain they experienced, and they avoid provoking it. To claim that animals can’t experience pain, you would have to explain how an animal can remember something it never experienced in the first place. I make this point of establishing the reality of animal pain in order to get to the critical issue, which is animal suffering.
Neuroanatomists, historically, have called a specific part of the human brain the “primitive brain.” This, like so much else in scientific terminology, is a metaphor. Just as the location(s) of an electron is/are not a cloud, and the brainstem is not involved in the passage of nutrients and water, the primitive brain is not really primitive. All vertebrate brains develop from the same set of embryonic neural elements (rhombencephalon, mesecephalon, etc.); some of these elements swell and crinkle, others don’t, depending on the species and what the species needs.
In any case, all of the parts are interconnected, and probably more so than we realize; at some point in the future, we may regard modern-day functional maps of the brain as just as quaint as those old-school phrenology maps showing character traits as bumps and spots on the skull. Having said that, some parts do very clearly handle the bulk of the processing of some kind or another. You compose language and speak it using Werneicke’s and Broca’s area; when I, as a radiologist, diagnose ischemia in those regions on an emergent head CT, I know in advance what the Symptoms section of the requisition is going to say: “Slurred speech.”
So: The primitive” brain was called “primitive,” from what I can tell (the term seems to have antedated or escaped the neuroanatomists and neurologists I trained under), because non-human forms of life often show a great deal of development and activity in this region. The brainstem handles some of the most basic functions of survival—like breathing and awareness; the next most “primitive” part of the brain is the limbic system, which in mammals handles, in ways that are still mysterious, emotion/aggression, smell, and memory.
It shouldn’t surprise us to find this triplet of functions clustered together. Consider how much non-human mammals rely on their sense of scent to recognize one another, distinguish food, hunt, and mark territory. To destroy a dog’s sense of smell would be the equivalent of blinding a human: The most highly developed and depended-upon sense, stripped. (Our hyperdeveloped visual cortex is responsible, incidentally, for the power of the climax of Oedipus Rex: Oedipus running through the palace without the sense of smell is not quite as hard-hitting. Likewise Milton’s Samson Agonistes: The image of Samson imprisoned in Gaza, stripped of the sense of taste, is hardly as full of pathos.)
Consider also how critical memory is to animals, whether they’re returning to hibernation sites, breeding grounds, or the nest or burrow where their young are, after a food-gathering expedition. This ability to memorize and navigate intricate details of the natural landscape used to be highly developed in aboriginal peoples; it hasn’t atrophied in us, either, as we use it every time we commute to work and back; but it is crucial that we see how the intellectual process involved in whale or bird migrations is worthy of respect: the storing of thousands of visual and (probably) olfactory cues, and the spatial orientation of the self and/or group in relation to them. We take it for granted, but it’s no mean feat. When it comes to memory, numerous animal species possess it, or carry out functions related to it, more elaborately than humans do. Elephants are just the most obvious example. The fact that the kind of information these species can remember differs from the kind we can—no multiplication tables, for example—should not be counted against animal memory.
All this points out a singular trend in the limbic system, this concatenation of basic brain functions. Olfaction and memory are, in more than one species, superhuman. How about the third function, the generation of aggression and the processing of emotion? These are very hard to study and quantify, far harder for example, than olfaction.
What kind of aggression? Is it survival-directed—like stalking, pouncing, killing, eating—or intended to demonstrate primacy for mating purposes—like the locking of antlers—or forced upon the aggressor—like soldiers fighting a modern oil war—or carried out for its own sake—like serial killing? I am not out to set up a research study here, but I would like to point out that some animals are more aggressive, by any measure, than human beings. Wolves show up in so many fairy tales for good reason. Apparently boars are perpetually belligerent, too; that’s the animal, remember, that gored Adonis in the classical myth. The wolverine (technically a weasel) shows up in modern mythmaking, with an eponymous character in the X-Men comics.
So far, every function of the limbic system has turned up more than one animal showing supercharged functionality, relative to us. Only one function is left in question: Emotion.
What are the emotions of animals? Does suffering require a reasoned perspective on pain, or is the negative emotion related to pain sufficient to qualify as suffering? If animal emotions are just as elaborate or intense as animal olfaction, animal memory, and animal aggression, if this function of the limbic system follows all the others, then inflicting pain on an animal would be (at least) as morally horrific as inflicting pain on an infant. An infant’s brain, on MRI, looks basically like a crinkly bag of water; the fat (myelin) hasn’t sleeved its axons yet, which accordingly don’t conduct as quickly; it has a rudimentary sense of self, no personality to speak of, and no “perspective” or rational insight into its own pain. In other words, it resembles any of a host of “lower,” non-human animals.
But it gets worse. Animal suffering, like infant suffering, is not the same as adult human suffering. Subjectively—and all suffering, like all emotion, is subjective—it may well be worse. Consider all the abstract thinking and advanced neurological processes that we use to combat suffering in ourselves—everything from religious consolations, to music, to conversations with friends. Suffering animals, like suffering infants, have no access to these. Adult human ways of combating suffering are consistently “higher” cortical processes—we can conceptualize them as descending, inhibitive impulses from higher cortical centers on the limbic system. Even the pills we take against pain and depression are examples of cerebral-cortex ingenuity at work. There is clear neuroanatomical evidence, correlated with animal behavior studies, that the occasional animal, like the orca, can possess hyperdeveloped limbic areas that are suspected to be the ones that process emotion. Animals are trapped in their bodies and are alone with their pain; they have no form of escapism, no pill, no way to neurocortically “rise above” their suffering.
I realize that the opposite argument could be made, too: That being rationally aware of your own suffering and impending death feeds back to emotional centers, producing a more intense, dinstinctly human form and intensity of suffering that animals know nothing of. This may be true. But the thinking assumes that all non-human animals lack reason, a bit of obvious-sounding falsehood which dates back I think to Aristotle, who never saw footage of a capuchin monkey cracking a nut with a rock. (Tool use is the first stirring of reason, in my opinion.) It also assumes that animals are incapable of being aware taht they are about to die and freaking out as a result of that, which is contradicted thunderously by every stampede of every herd ever. Reason or no reason, conscious suffering or non-conscious suffering—note that we never extend this reservation to the suffering of human infants. In any case, the point of this essay was not to engage in oneupmanship in some kind of Relative Suffering Competition; the point of this essay was to answer a question.
Do animals suffer? The question seems to have been posed by our billion-dollar, animal-exploiting industries themselves; the question gives people the option of answering “No.” Based on the little we know for sure about human and animal brains and behavior, the question needs to be refocused: Not whether or not animals suffer, but whether or not they suffer more intensely than human beings. Whether their emotional response to pain is commensurate to their sense of smell and their faculty of memory.