Are there limits on how human beings can legitimately treat non-human animals? Or can we treat them just any way we please? If there are limits, what are they? Are they sufficiently strong, as some people suppose, to lead us to be vegetarians and to seriously curtail, if not eliminate, our use of non-human animals in `scientific' experiments designed to benefit us?

To fully appreciate this question let me contrast it with two different ones: Are there limits on how we can legitimately treat rocks? And: are there limits on how we can legitimately treat other human beings? The answer to the first question is presumably `No.' Well, that's not quite right. There are some limits on what we can legitimately do with or to rocks. If Paula has a pet rock, then Susan can't justifiably take it away or smash it with a sledge hammer. After all it is Paula's rock.

Or if there is a rock of unusual beauty or special human interest say the Old Man of Hoy or Mt. Rushmore it would be inappropriate, and probably immoral, for me to tear it down, to deface it, or to chisel out a section to use in my catapult.

These limits though, arise not from any direct concern for the rocks; rather, they are imposed because of the interests and rights of other humans. Susan can't take Paula's rock for the same reason she can't take Paula's eraser: it is Paula's and Paula has a right to those things which are hers. And no one can destroy or deface items of special natural beauty because by doing so one is indirectly harming the interests of other humans in them. So there are limits on what we can legitimately do to inanimate objects, but whatever limits there are arise from some human concern.⁽¹⁾

Not so for our treatment of other humans. We suppose that it is inappropriate to treat a human being just any way we wish. I cannot steal another human; that would be kidnapping. Nor can I smash someone with a sledgehammer; that would be, depending on the outcome, assault, attempted murder, or murder. And the reason I cannot do these things has nothing to do with what third parties do or don't want. It has to do with the interest and desires of that particular person. It is wrong for Susan to hit Paula, not because other people like Paula or because other people would be offended, but because Paula is a person. Period.

Thus, there is a fundamental contrast between those objects which we can treat as we please (except when limited by the interests of other humans) and those which we cannot. Ordinary rocks fall into the first camp; humans, into the later. Now, what about non-human animals? Do they fall into the first or the second camp? Or somewhere in between?

There are reasons to believe that many animals and certainly the higher-order animals are more like humans than they are like rocks. Thus, we have reason to believe there are constraints on how we can legitimately treat them, regardless of our particular wishes and desires. Or so I shall argue.

For the moment I will simply note that these are beliefs which most of us already have. That is, most of us presume that it is illegitimate to treat animals just anyway we wish. For example, most of us believe it is wrong to wantonly kill or torture a higher order mammal. Suppose we discover that some member of our community, say Jones, has a habit of picking up stray dogs or cats and decapitating them with his home-made guillotine';⁽²⁾ or we learn he has invented a machine which draws and quarters them. He uses these machines because he revels in the animals' pain, because he relishes in the sight of blood; or maybe he is a scientist who wants to study their reaction to stress. In this case we rightly surmise that Jones is immoral. We wouldn't want him to be our president, our friend, our next door neighbor, or our son-in-law.

In short, we all seem to agree that they are limits on how we can properly treat non-human animals, and that these limits arise because of the nature of the animals, not merely because of the desires of other humans to see animals treated well. That is, such acts are wrong not merely because other humans are bothered by them. We would think them equally wrong if they were secretly done so that no one else in the community knew about them. We think they are wrong because of what it does to the animal.

On the other hand, we are also part of a culture which rather cavalierly uses animals for food, for clothes, for research in the development of new drugs, and to determine the safety of household products. And many of these uses require inflicting a great deal of pain on animals. Record of such uses is readily available in various academic journals, and chronicled by numerous writers on the topic' (Ryder, 1975; Singer, 1978; Mason and Singer, 1980). But for the reader who might be unfamiliar with them, let me briefly describe two ways in which we use animals ways which inflict substantial pain on them.

Animals who are raised for food are obviously raised with the express purpose of making a profit for the farmer. Nothing surprising. But the implications of this are direct and obvious and deleterious to the animals. There are two ways for a farmer to increase her profit. One is to get higher prices for her goods, the other is to spend less producing those goods. Since there is a limit on how much people will pay for meat, there is substantial financial pressure to decrease the expense of producing the meat.

This understandably leads to over-crowding; after all the more animals a farmer can get into a smaller space, the less it costs to produce the meat. There are similar pressures to restrict the animals' movement. The less the animals move, the less they eat, thus decreasing the farmer's expense. For instance, farmers who raise chickens are inclined to put them in small `battery' cages. They are commonly kept `eight to ten to a space smaller than a newspaper page. Unable to walk around or even stretch their wings much less build a nest the birds become vicious and attack one another' (Rachels, 1977).

The average person seems equally unfamiliar with the extensive use of animals in laboratory experiments. Many of these are of only moderate significance';⁽³⁾ most of the them involve extensive pain on animals. For instance, N.J. Carlson gave high voltage electric shocks to sixteen dogs and found that the `high-shock group' acquired `anxiety' faster. Or researchers in Texas constructed a pneumatically driven piston to pound an anvil into the skulls of thirteen monkeys. When it didn't immediately produce concussions, the researchers increased the strength of the piston until it produced `cardiac damage, hemorrhages and brain damage' (Ryder, 1976). Or researchers at Harvard placed baby mice and baby rats into cages with starving adult male rats. The adults ate them. The researchers' conclusion: hunger is an important drive in animals. (That, of course, is something we are shocked to learn; we would have never known this fact otherwise).

The Options

Now, how do we square our absolute revulsion at our hypothetical Jones with his animal guillotine, and our rather blithe acceptance of the treatment of animals on the farm and in the scientific and commercial laboratories? It is not immediately clear that we can. What is clear, it seems, it that we have three options, three alternative beliefs about our treatment of animals. These are:

1) If we are repulsed by Jones treatment of stray animals, we are simply being inappropriately or unduly squeamish or sympathetic. We should have no aversion to killing, torturing, or using animals in any way we please, unless, of course, that animal is someone else's property, that is, her pet.

2) There are reasons why we should treat non-human animals better than we treat rocks; nonetheless, there are also reasons why we can use non-human animals in ways we could never legitimately use humans.

3) We should be treating non-human animals more like we currently treat humans. Many of our accepted ways of using animals are, in fact, morally objectionable.

The first position, it seems, is completely untenable. No sensible person, I think, is willing to adopt a position which says that torturing animals for fun is completely acceptable; no one is willing to say that Jones is a fit member of society. This belief, it seems, is virtually unshakable. Most of you understood perfectly well what I meant when I described Jones's behavior as `torture.' But this claim would be nonsense if we thought there were no moral limits on how we could treat animals.⁽⁴⁾ So we are left with the latter options. And, of course, which one we choose, will have a dramatic impact on the lives of humans and of other animals.

One necessary clarification: to say that animals should be treated more like humans is not to say that they should be treated exactly like humans. For instance, we need not consider giving animals the right to vote, the right to free religious expression, or the right of free speech. As far as I can ascertain, most animals don't have the necessary capabilities to exercise these rights. However, the same is true of very young children and of severely retarded adults. That is why they don't have these rights either: they lack the requisite capacities. Nonetheless, the mere fact that some adult humans are not given the right to vote does not mean it is legitimate to have them for lunch or to test bleach in their eyes. So why assume it is so for animals?

Why animals shouldn't suffer needless pain

Until now I have been trying to identify our own deeply held convictions about restrictions on the proper treatment of animals. Now it is high time to try to offer a positive defense of our ordinary understanding; a defense which will have even more radical implications that we might have supposed. That is, I want to argue for option three above; I want to argue that there are rather stringent limits on what it is morally permissible to do to animals. More specifically, I wish to argue that we should all become vegetarians and that we should dramatically curtail, if not eliminate, our use of laboratory animals.

Though there are numerous arguments which can be offered in this regard, I want to defend one particular claim: that we should not inflict needless pain on animals. Before I go on I should make it clear what I mean by `needless pain.' The point can be made most clear by use of an analogy.

Contrast the following cases: 1) I prick my daughter's arm with a needle for no apparent reason (though we needn't assume I derive any sadistic pleasure from it). 2) I am a physician and I inoculate her against typhoid. What differentiates these cases? In both I prick her arm; in both (let us presume) I inflict similar amounts of pain. Yet we consider the latter not only justifiable, but possibly obligatory; the former we consider sadistic. Why? Because it inflicts unnecessary pain. My daughter does not in any way benefit from it. Thus, unnecessary pain is that which is inflicted on a sentient (feeling) creature when it is not for the good of that particular creature. The latter is necessary pain; it is pain which the creature suffers for her own good.

There are two main premises in my argument. The first is the factual claim that animals do, in fact, feel pain. The second is the claim that the potential of animal suffering severely limits what we can justifiably do to them, it constrains the way we can legitimately use them.

That animals feel pain
That animals do feel pain seems relatively uncontroversial. It is a belief we all share. As I noted earlier we couldn't even make sense of `torturing' an animal if we assumed it was incapable of feeling pain. Nor could we understand being repulsed at Jones's use of stray animals unless we thought the animals suffered at Jones's hands. If Jones collected abandoned tin cans and cut them to pieces with his guillotine, we might think Jones terribly odd, but not immoral.

But more can be said. We have more than adequate behavioral evidence that animals feel pain and that they can suffer. Most of us have seen a dog which has been struck by a car, though not killed instantaneously. The dog convulses, bleed, and yelps. Less drastically, most of us have, at some time or another, stepped on a cat's tail or a dog's paw and have witnessed the animal's reaction. The reaction, unsurprisingly, is like our own reaction in similar cases. If someone steps on my hand, I will likely yell and attempt to move my hand.

But we needn't rest the case on behavioral evidence though it does seem to me to be more than sufficient. We should also note that we share important anatomical structures with higher order animals. A human being's central nervous center is remarkably similar to that of a chimpanzee, dog, pig, and even a rat. That is not to say the brains are exactly alike; they aren't. The cerebral cortex in human beings is more highly developed than in most mammals (though not noticeably so when compared with a dolphin or a Great Ape); but the cortex is the location of our `higher brain functions,' for example, the seat of thought, speech, etc. However, the areas of the brain which neurophysiologist identity as the `pain centers' are virtually identical between human and non-human animals. According to evolutionary biology this is exactly what we should expect. The pain centers worked well in enhancing the survival of lower species, so they were altered only slightly in succeeding evolutionary stages. Higher brain functions, however, are conducive to survival, and thus, have led to more dramatic advances in cerebral development. Given all this, it seems undeniable that many animals do feel pain.

That they feel pain is morally relevant
'So what?' someone might ask. `Even if animals do feel pain, why should that limit or at least seriously restrict our treatment of them? Why can't we still use them for our purposes, whatever those purposes happen to be?'

Let's turn the question around for a moment and ask why we think we should be able to use them for our purposes, given that they are capable of suffering? After all, we are staunchly opposed to inflicting unnecessary pain on human beings. If animals can also feel pain, why shouldn't we have the same reluctance to inflicting needless pain on them?

A crucial tenet of ethics is that we should treat like cases alike. That is, we should treat two cases the same unless there is some general and relevant reason which justifies the difference in treatment. Thus, two students who perform equally well in the same class should get the same grade; two who perform rather differently should receive different grades. By the same token, if two creatures feel pain and it is improper to inflict needless pain on one of them, it would likewise be improper to inflict needless pain on the other.

But the argument has progressed too quickly. This argument works only if the reason it is wrong to inflict needless pain on the one creature is that it feels pain. If there is some other reason some reason which could differentiate human from non-human animals then we would not be able to infer that it is illegitimate to inflict needless pain on animals. Hence, if someone wishes to show that it is not wrong to inflict needless pain on animals, then she must identify some relevant difference between human and non-human animals, some difference which justifies this difference in treatment.

And, of course, this is just what most defenders of our present treatment of animals are inclined to do. Though people once regarded animals as non-sentient creatures as mere automata that is no longer so. The belief that animals are incapable of feeling pain is not tenable in the face of all the behavioral and scientific evidence. So the usual move is to find some other difference which is thought to significantly distinguish humans from animals.

The most frequently cited and promising candidate: rationality or the sense of oneself as a continuing being. Humans, it is said, can reason and think; animals (it is presumed) cannot. Moreover, this ability to reason becomes reflected in the human's ability to see herself as a continuing creature as a being which has a past and will have a future.

Let us grant for a moment that humans are rational and animals aren't; that humans have a sense of themselves as continually existing beings and animals don't. Why should that make any difference? Or more precisely, why should it make as much a difference as it does? Does the fact that we are rational legitimate our using non-rational animals just anyway we please?

It seems not. It certainly doesn't legitimate abusive treatment of other humans. Some human beings are severely retarded or are in irreversible comas, and thus are no more rational than are the animals. Yet we think it would be inappropriate to use these humans either to ascertain the effects of ammonia on the skin or to charbroil them for supper. We assume that doing so would violate their rights. So why shouldn't we be equally reluctant to use animals in these ways? (If you find the suggestion of using humans in these ways repulsive, ask yourself: why is it so easy to use animals in these ways?) So rationality does not appear to be the foundation of the wrongness of inflicting needless pain on humans.

Moreover, we can imagine a seemingly analogous, through contrasting situation. Suppose a race of super aliens came to Earth, aliens whose intelligence was vastly superior to ours. Let us suppose they were brighter relative to us than we are relative to other mammals. If that happened (even though we suppose that it won't) would these aliens be justified in roasting us or using us to test some new cleanser for their spacecraft? I would surely have thought (and hoped) not. If they aren't, it seems we must conclude that intelligence and rationality do not justify our belief that it is wrong to inflict needless pain on humans.

Finally, we can note that the traits in questions are more properly associated with rights other than the right not to suffer needless pain. Rationality is more closely linked with rights to vote, free speech, etc., while the ability to perceive oneself as a continually existing being seems more closely associated with a right to life. (After all, death is not feared by a being who has no sense of itself existing in the future.) In contrast, the right not to suffer needless pain seems linked to just one trait, namely, the ability to feel pain. If humans had no pain center if they did not experience pain then they would not have a right not to suffer needless pain, no matter how intelligent or rational they were. Consequently, it seems that it is morally impermissible to inflict unnecessary pain on animals.

Objections to my view

Animal suffering is not unnecessary
Someone might grant all this yet contend that our use of animals is acceptable since the suffering of animals is not really needless. After all, most humans eat animals, and thereby gain nutrition from them; animal experimentation is a significant and vital part of our attempt to discover cures for devastating human disease and to protect humans from the introduction of possibly dangerous commercial products.

Doubtless it sometimes benefits humans to use animals in these ways. But is it genuinely necessary? Not obviously. For example, though most humans do receive some valuable nutrition by eating animals, there are more than adequate alternatives. One never need eat meat to be extremely healthy. In fact, vegetarian diets may be extremely beneficial; those on vegetarian diets, for instance, have less incidence of certain forms of cancer. Hence, the primary reason people are carnivores rather than vegetarians is that they prefer (or think they prefer) the texture of meat over the alternatives.⁽⁵⁾ But surely having one's taste buds excited in a certain way is not sufficient reason to inflict substantial pain on animals. To refer back to an earlier case: Jones may derive great pleasure from torturing stray animals, but that doesn't justify his torturing them.

Certainly too, many experiments on animals are unnecessary. The experiment may be senseless, or continually duplicated. Many experiments are doubtless motivated merely by the desire to receive a new publication (if one is an academic) or to market the 97th brand of toothpaste. Moreover, many critics have claimed that the vast majority of experiments can be done as well, if not better, using computer simulations and cell cultures' (Pratt, 1980).

I think the critics are obviously right in saying that many of the experiments are totally unnecessary that they just don't need to be done or that the desired goal can be reasonably accomplished in some feasible, alternative way. Nonetheless, perhaps there are some goods which can only be achieved or at least achieved quickly by the use of animal experimentation.

But why should we suppose that justifies inflicting extreme pain on the animals? It seems at least equally plausible to assume that there are some scientific gains than can be attained only through research on human beings. In fact, that is exactly the claim the Nazi's made when they conducted their `scientific experiments' on their Jewish detainees. Yet we presumably think that such experiments are morally objectionable no matter what good can (or did) come from them. Humans simply should not be used in such ways. But then why suppose animals can be?

It seems we face the following dilemma: either the laboratory animals are or are not sufficiently like us so that the studies on them can be generalised to human beings. If they are not sufficiently like us to warrant generalizing the experimental findings to humans, then the experiments do not do what they purport to do and thus, are senseless. On the other hand if the animals are sufficiently like us to warrant generalizing the findings to humans, then they are sufficiently like us so that we should presume that such experimentation is immoral. So either way, the experimentation is unacceptable.

I agree that this conclusion seems far too strong. We all see the benefits which can accrue from certain forms of medical research. It might even be that some limited forms of research can be justified though I am suspicious that it cannot. Nonetheless, if such research could be justified, that would in no way undermine the fact that the vast majority of laboratory research on animals could not be.

Sentience is not enough
Some commentators, most notably R.G. Frey, (1980) have argued that though animals are sentient, they are not sapient, that is, that cannot reason. Thus, he claims (to resurrect an earlier argument) we can use them for our own purposes.

Earlier I tried to argue that the animals need not be sapient to deserve our respect. The mere fact that they can feel pain grounds the claim that it is wrong to inflict needless pain on them. Now I want to challenge Frey's contention that animals are not rational. He contends that animals cannot reason. Any animal behavior which looks rational, he claims, is merely instinctual. To be rational one has to be able to have beliefs, and we have no reason to suppose that animals have beliefs. Why? Because they do not have the genuine use of language. Nor are they capable of lying, of deliberately telling a falsehood.

The claim that these animals do not have language or thought seems highly questionable. A number of studies with chimpanzees and apes have shown that they have the ability to learn sign language (Gardner and Gardner, 1969). Once they have mastered the language they communicate with the other humans; some have been known to teach the sign language to other apes.

Frey, however, claims that this behavior is mere mimicry or a response to stimulus. That seems wrong. For several of the animals have been shown to combine the words in ways they had never learned them in short, to create new words. Moreover, there is at least one reported case of a baboon's lying. And some researcher's have claimed that dolphins are capable of learning syntax (rules of grammar) as well as the meaning of certain words (Griffin, 1976). Given that such experiments are fairly new and have been promising we should conclude with Griffin, that animals even animals considerably far down the evolutionary chain may be capable of at least rudimentary thought.

What if we raised animals humanely?

Someone might object to my account in the following way: I have argued that we should not inflict needless pain on animals. But what if we were to rear them humanely and kill them quickly (and thus, relatively painlessly)? Would my argument give any reason to suppose that eating animals under these conditions would be wrong? If not, on what grounds could one plausibly object to eating meat in these circumstances?

This is an interesting theoretical question. But before I attempt to answer it, I should make it clear that the answer has no bearing on how we ought to act in the present situation. As I noted earlier, there are potent economic considerations which make humane rearing of animals highly improbable. Consequently, we will likely never have to decide whether we should eat animals reared humanely. Hence, even if it were morally permissible to eat meat in these imaginary circumstances, it would still be impermissible for us to eat meat in the actual circumstances (though, of course, none of this precludes working for more humane methods of raising farm animals).

Second, if contrary to all reasonable expectations, we were to begin to raise farm animals humanely, the resultant meat would be so costly that consumption would be severely limited. Hence, once again, it is likely that few of us would be faced with a real dilemma about whether to eat animals reared humanely.

But let us suppose, contrary to fact, that we could obtain meat from animals who suffered only slightly (either because the meat was reasonably priced or because we were wealthy). Would it then be morally permissible to eat them? The answer here, it seems, is more complicated. I have been concerned primarily to show that our present treatment of animals is morally indefensible since the practice of factory farming causes them substantial unnecessary pain. Thus, the relevance of my argument to this hypothetical case is not obvious.

I chose to use the argument I did because it was simple, yet convincing. That is, it seems virtually indisputable that it is wrong to inflict unnecessary pain on sentient creatures, and that our present practices do, in fact, cause animals such pain. Moreover, since our only genuine option is whether to eat animals reared in inhumane ways or to become vegetarians, then this argument is more than sufficient for the purposes at hand. Nonetheless, it does seem appropriate at the end of the paper to engage in some speculative flights of fancy.

My own, somewhat tentative, view is this: the argument from necessary pain helps one realize that there are moral limits on how we can legitimately use animals. Moreover, these limits emerge because of the interests of the animals themselves, not because of any parasitic interests which humans have in them.

But that is just to say that the animals are, in at least some significant sense, ends in themselves, things which cannot be legitimately used merely as means for human ends. If, however, their being ends in themselves makes it illegitimate to inflict pain on them to satisfy our taste buds, it seems it might also be unreasonable to kill them to stimulate our taste buds -- even if they had been raised humanely.

Now I recognize this response will not be entirely convincing. That is not surprising. I am not even entirely convinced of its force. Nonetheless, it appears to be a plausible extension of the earlier argument. And even if it is not wholly adequate, I am inclined to adopt a principle of conservatism here: that it is better to refrain from actions which might well be seriously immoral (even though one is not sure they are) if the potential gains from the questionable action are minimal; having ones taste buds stimulated in a certain way seems clearly to be minimal. Moreover, since the moral choice we actually face is not how we would act in this hypothetical case, but how we should act in the real world, then this admission is not in the least damaging to the argument presented here.

Conclusion

I realize that the claim that there are substantial moral limits on the way we can legitimately treat animals is rather at odds with our inherited attitude toward them. For though most people think it is wrong or at least tacky to torture animals, most generally assume animals are here for our use. To that extent my view is a radical departure from our culture inheritance. But in the light of the previous arguments, it is a well-merited departure.

Exactly where this view leads I do not know. I don't know if all animals experimentation is unjustified, I do not know exactly how to deal with certain pests, what to do with current livestock, etc. But the fact that all the details are not worked out does not count against the claim that our present view is morally unacceptable.

When women first started pressing for the right to vote or for equal rights in general they did not know exactly where their claims would lead us. They still don't; nor do I. But I am quite confident that it is a change for the better, even though the specific details of the changes will only unfold with time. The same is true for our treatment of animals. Maybe one day our children will look back on the current generation and wonder how we ever believed it was tolerable to treat animals the way we do. I sincerely hope so.

1. Actually I think the situation is a good deal more complex than I have suggested. There is a great deal to be said for the claim that there are limits on what humans can legitimately do to inanimate objects, and that those limits are not exhausted by human interests in them. But that position is admittedly controversial. Moreover, I can make the point I wish to make about animals without relying on it. So for the moment, at least, I will act as if the only constraints on our behavior toward inanimate objects stem from human interests. Other essayists will doubtless discuss the broader environmental concerns in their essays.

2. This example is not, as you might have supposed or hoped a mere piece of fiction. Some research scientists purchase miniature guillotines made especially for beheading laboratory rats. Advertisements for these devices frequently grace the pages of veterinary journals.

3. Professor Harry Harlow, whose research on baby monkeys is known world-wide said, `most experiments are not worth doing and the data obtained are not worth publishing,' in Journal of Comparative and Physiological Psychology. 1962).

4. I will now cease referring to `non-human animals' and, from here on out, refer to them simply as `animals.' The longer locution, though more accurate, is simply too cumbersome.

5. I say `think they prefer' because I have seen numerous people who have discovered, after eliminating or even cutting down on meat, that their diets are more varied and more tasty than when they were carnivores.

Frey, R.G.,Interests and Rights, Oxford, The Clarendon Press, 1980.

Gardner, B.T. and Gardner, R.A., `Teaching Sign Language to a Chimpanzee,' Science, 165: 664-72, 1969.

Griffin, D.G., The Question of Animal Awareness: The Evolutionary Continuity of Mental Experience, New York, The Rockerfeller University Press, 1976.

Mason J. and Singer, Peter. Animal Factories, New York, Crown Publishers, 1980.

Pratt, D., Alternatives to Pain in Experimentation on Animals, New York: Argus Archives, 1980.

Ryder, Richard, `Experiments on Animals,' in Animal Rights and Moral Obligation. ed. T. Regan and Singer, Englewood Cliffs, NJ, Prentice-Hall, Inc., 1976.

Ryder, Richard, Victims of Science: The Use of Animals in Research, London, Davis-Poynter, 1975.

Rachels, James, `Vegetarianism and the "Other Weight Problem,"' in World Hunger and Moral Obligation. ed. W. Aiken and H. LaFollette, Englewood Cliffs, NJ, Prentice-Hall, Inc., 1977.

Singer, Peter, Animal Liberation, New York, Avon Books, 1978.