It seems to be a common opinion among atheists and scientists that the animal-rights movement is ridiculous, and I’ve seen it criticized and mocked on many secular websites. And indeed, the tactics of some animal-rights groups, like PETA, have been such as to offend or turn off many people. PETA, for instance, shows ads featuring semi-clad women, and even though the ads are promoting vegetarianism and the non-wearing of fur, I know women who find them sexist, for where are the naked men? More important, PETA and other groups have engaged in violent activities, threatening researchers and trashing labs, and freeing lab animals that could never find an alternative home. Finally, some animal-rights groups decry owning pets (excuse me, “companion animals”), on the grounds that this leads to overpopulation of unwanted pets as well as stressful confinement of animals like cats and dogs, who still have their evolutionary instincts to roam free.

But regardless of the invidious tactics of some animal-rights groups, the general point stands: if you think animals are capable of suffering, and they are, then don’t they at least have some of the “rights” that we reserve for humans? Isn’t the criticism of groups like PETA, or the kneejerk feeling that any experimentation on animals is justified so long as it has potential to save human lives, simply something that we espouse to avoid thinking about the important issue of animal suffering?

Yesterday I saw a photo in the New York Times of a turkey farm (Thanksgiving is upon us); in it a farmer was standing in a huge building in which turkeys, obviously stressed, were packed wing to wing. (See photo at boottom.) The birds had no room to roam, and it was disturbing. Experiments have shown that chickens, for instance, much prefer wandering on grass than standing in wire cages. And what we do to chickens—confining them in cages, clipping their beaks, and crowding them horribly—is unjustifiable if you think that these animals suffer. The evidence suggests that they do, and who with a scientific and empathic turn of mind could deny that suffering, or the proposition that animals feel pain?

And the suffering we inflict on chickens also applies to many of our other food animals. Driving through Texas and the Midwest last summer, I saw cows crowded together in feedlots, getting fattened up before the slaughter. The lots were simply bare expanses of mud filled with stinking cow dung that you could smell miles away. I have no doubt that those animals were stressed.

These thoughts were prompted by a good book I’m reading, Darwin, God, and the Meaning of Life, by Steve Stewart-Williams (2010; Cambridge University Press). The book is the best discussion I’ve seen about the philosophical implications of the theory of evolution; and believe me, there are philosophical implications—dealing with issues like the existence of the soul, the nature of morality, and human exceptionalism. I recommend it highly: Stewart-Williams, an associate professor of psychology at Nottingham University, Malaysia Campus, writes very well and has thought deeply about these issues. Even if you think you understand the implications of evolution for your own worldview, you’ll still learn a lot.

At any rate, Chapter 13, “Uprooting the doctrine of human dignity,” contains this paragraph near the end:

Singer [Peter Singer, author of the excellent book Animal Liberation: A New Ethics for our Treatment of Animals] makes the extremely interesting and challenging point that the amount of suffering and pain caused by the tyranny of human beings over animals (particularly in food production) far exceeds that caused by sexism, racism, or any other existing forms of discrimination, and for that reason the animal liberation movement is the most important liberation movement in the world today. Women and disadvantaged ethnic groups have never been farmed, killed for sport, or systematically experimented on in anything like the numbers that non-human animals have. Furthermore, unlike women and slaves, non-humans cannot talk or campaign for their own liberation, and, because they can’t vote, they’re not a high priority for most politicians. This further underscores the importance of the animal liberation movement.

I see a lot of sense in that. For, when you think about it, evolution teaches that for some traits we’re different quantitatively but not qualitatively from our animal relatives, and that they, like us, can suffer and feel pain. Perhaps humans, because we have greater rationality and the presence of culture, may suffer more than some animals, but can you really say that a gorilla or chimp who is captive in a zoo, or subject to experimentation to cure human diseases, isn’t suffering? (Recognizing this, the US National Institutes of Health just joined many other countries in ending “invasive research” on chimpanzees.)

Those are our primate relatives, but what about guinea pigs, mice, and laboratory cats and dogs? They are subject to horrible procedures that cause them to suffer, not even considering just their confinement. People automatically assume that this is okay if such experimentation will save human lives, but how many dog, cat, or mouse lives are worth one human life? Could it be justified, as Stewart-Williams asks, to experiment on humans, killing a few humans to save thousands of chimpanzee lives? If not, why not? Why is the saving of human life worth the expenditure of vastly more animal lives, and perhaps—adding it all up—the greater suffering of animals than of humans?

It’s even less justifiable to eat factory-farmed animals, I think, for we can live without eating them. Why—and I am complicit in this—do we simply ignore all that suffering so that we can have a nice roast chicken or a plate of fried eggs on our tables? In our hearts we know that animals suffer to give us that food. Is their suffering truly worth nothing?

We need to face the fact that if we really care about suffering, there is no justification to limit our concern to the suffering of Homo sapiens. That’s especially true because, as Stewart-Williams argues, we cause immensely greater suffering of animals, and they have no representation save groups like PETA. If evolution and science tell us anything, it is that animals suffer as we do—perhaps not as intensely in cases like the death of a relative—and that many species are apparently conscious, and surely many feel pain. By what right do we ignore all of that when doing so is just a convenience for our own species? Is any amount of animal experimentation and suffering justified by its potential to save human lives? If so, why?

Few people have come to grips with these issues. Singer is one, Stewart-Williams another. But we need to face those issues if we’re to be consistent in our concern for the suffering of the disadvantaged. As for me, I feel pretty bad about all this, and consider myself a hypocrite for eating eggs and meat. I don’t know if I’ll do something about that, but at least we can oppose the confinement of animals in zoos, and agitate for humane treatment of the animals we put into our stomachs.

Here’s the picture from the New York Times that disturbed me; it’s from an article called “After bird flu scare, plenty of turkeys for Thanksgiving.”