We have an obligation not to cause suffering. Furthermore, we have no reason to limit this obligation to members of the human species—any sort of suffering is morally relevant, and the importance of the suffering derives not from who experiences it but from how severe it is . If animals can suffer then their suffering deserves equal consideration.
Many non-human animals (including most vertebrates) are definitely capable of suffering—physically, and often emotionally. True, most animals cannot know the range of suffering that humans can, but they still feel pain, discomfort, and distress, and they experience such feelings as acutely (or at least approximately as acutely) as humans do. (For those who doubt that mammals and other vertebrates feel pain to the extent that humans do, see Do Animals Feel Pain?.) We owe it to all animals—human and non-human—not to inflict painful experiences upon them. Furthermore, we have an obligation to prevent the suffering of animals in the wild.
If we grant that the suffering of all beings holds equal value, then what must we do to remain consistent with our morals?
It has been well-established that factory farms—through which nearly all domesticated animals (excluding pets ) are raised—cause animals a great deal of suffering. This essay will not go into details, as facts about such animals’ treatment are readily available (in many books as well as on the web; I recommend Peter Singer’s Animal Liberation, an excerpt of which may be found here). All that need be said here is that animals on factory farms experience an enormous, almost incomprehensible amount of suffering for their entire lives.
So-called “free range” or “cage-free” farms, while they often improve conditions, still create considerable suffering. It is difficult to find farms that raise animals humanely, and even certified “humane” farms create conditions that I would not wish for any sentient being to endure (for example, castrating animals without anesthetic). It may be possible to find happily-raised animals in stores, but I warn the reader to be skeptical of any products that claim to be humane. For more information, see “The Truth Behind Labels: Farm Animal Welfare Standards and Labeling Practices.“
In addition to causing unprecedented levels of animal suffering, factory farming heavily contributes to global warming—more than the entire transportation sector, according to the United Nations. (Perhaps strangely, advocates for solutions to global warming often overlook this factor.)
In light of these considerations, we hold an obligation to avoid animal products, especially food. Of course, reducing the quantity of meat one eats—while not as good as removing it entirely from one’s diet—does a great deal of good. For those who wish to prevent animal suffering but find it difficult to do so, there are a lot of resources out there that can help you. I recommend The 99-Cent Ultimate Vegan Guide by Erik Marcus, which you can purchase online for 99 cents.
Of all the animal products we consume, chicken and fish suffer the greatest total harm. A cow or a pig can feed many more people than a chicken or fish, so not as many have to be raised and killed in cruel conditions. And when industrial fishing boats capture fish, they end up killing many times more fish than they actually intend to harvest, simply by accident (Foer 49). Together, chicken, eggs, and fish probably account for over 95% of the suffering that the food industry creates. For more information on this subject, see “How Much Direct Suffering Is Caused by Various Animal Foods?”
One should avoid animal products not only to reduce suffering, but to make a statement. We will make serious progress toward reducing animal suffering when caring seriously about animals becomes a widely-accepted position. As it is, people who concern themselves with the suffering of non-human animals are considered radicals and often looked down upon—many consider it rude to even bring up the fact that you’re vegan. Every person who joins this “radical” position helps push it toward the mainstream; and the more mainstream the position becomes, the easier it will be to reduce animal suffering. Similarly, it is important to behave respectably when it comes to animal welfare issues; if you behave respectably, your position will get more respect. Incendiary organizations such as People for the Ethical Treatment of Animals can hurt the credibility of the animal welfare movement.
Other actions we can take include political action (such as lobbying for stricter legal standards for factory farms) and donating to charities that support animal welfare. Philosopher Brian Tomasik conducted a cost-benefit analysis of one charity, Vegan Outreach, and found it to be highly cost-effective.
I hear people give reasons why they cannot be vegetarian or vegan. It goes beyond the scope of this essay to address them all, but it is worth saying this: (a) extensive research has shown that a vegan diet can be healthy for humans in every stage of their lives (see this report by the American Dietetic Association); (b) I have never heard someone raise a problem that could not be solved by Googling it. (For example, a common complaint goes, “I can’t get enough protein.” Myriad sources in bookstores and on the internet explain how to eat adequate protein with a plant-based diet.)
The Importance of Animal Suffering
Given the sheer volume of factory-farmed animals, the meat industry represents one of the most serious problems facing the world today. Most people—including many vegetarians—grossly underestimate the importance of this issue.
Non-human animals clearly have many differences from humans: they cannot vote, they cannot attend school, and they cannot in most ways participate in human society. However, many species can suffer just as we can, and as such deserve moral consideration.
As Jeremy Bentham put it in An Introduction to the Principles of Morals and Legislation:
The day has been, I am sad to say in many places it is not yet past, in which the greater part of the species, under the denomination of slaves, have been treated by the law exactly upon the same footing, as, in England for example, the inferior races of animals are still. The day may come when the rest of the animal creation may acquire those rights which never could have been witholden from them but by the hand of tyranny. The French have already discovered that the blackness of the skin is no reason a human being should be abandoned without redress to the caprice of a tormentor. It may one day come to be recognised that the number of the legs, the villosity of the skin, or the termination of the os sacrum are reasons equally insufficient for abandoning a sensitive being to the same fate. What else is it that should trace the insuperable line? Is it the faculty of reason or perhaps the faculty of discourse? But a full-grown horse or dog, is beyond comparison a more rational, as well as a more conversable animal, than an infant of a day or a week or even a month, old. But suppose the case were otherwise, what would it avail? The question is not, Can they reason? nor, Can they talk? but, Can they suffer?
Any fair-minded ethical theory must grant that suffering is equally significant no matter who experiences it, and that includes non-human animals.
Humans living in factory farm-like conditions would probably suffer worse than other animals because out higher reasoning capacities would create additional forms of suffering. However, the great majority of human suffering in such a situation would arise in the very same manner in which animal suffering arises: continual physical pain and discomfort, inability to form social connections, and severely limited emotional freedom. Considering the tens of billions of animals raised in such conditions for their entire lives, it should be no surprise when I claim that factory farming represents one of the greatest evils in existence.
That said, the single most important source of suffering that we know of must be wild-animal suffering. Due to the sheer number of wild animals, they experience far more suffering than animals in factory farms.
Unfortunately, it does not look like we can do much about it right now, as we are not very good at predicting the impact of our actions. It is likely that our efforts to help will only make the situation worse. So consider this an open problem. We ought to spend time considering what we can do to alleviate the suffering of wild animals without inadvertently creating more. Perhaps we do not yet know what to do, but we have not spent much time considering the problem.
For now, we should stop using animal products, help promote moral sentiments that give consideration to animal suffering, and consider donating to effective animal-welfare charities.
 When I spoke to a friend of mine about the subject of this essay, he argued that human well-being is necessarily more important because humans have a greater impact on the global well-being than other species. If this is true, it does not give greater inherent value to human happiness, but rather gives them greater value because they create more significant side effects.
If a single human becomes more happy, his happiness spreads to other people—and hence, increasing a human’s happiness by X amount generally does more good than increasing a non-social animal’s happiness by X amount. But the added impact from a human’s happiness still does not compare to the extraordinary amount of suffering a human can prevent by taking on a few minor inconveniences (as described later in this essay).
 Factory farms represent the biggest source of suffering that humans inflict upon animals. This essay does not address the exploitation of animals for clothing, experiments, zoos, etc., because the sheer number of animals in factory farms far exceeds the number of animals in zoos and laboratories. And this essay excludes pets because we treat pets much better than most animals.
Foer, Jonathan S. Eating Animals. New York, NY: Hachette Book Group USA, 2010. Print.