Interview with Peter Singer

«Some humans are not persons, and some nonhuman animals are persons»

Philosopher and Professor of Bioethics at Princeton.

Peter Singer

Peter Singer is Ira W. DeCamp Professor of Bioethics at Princeton’s University Center for Human Values. Often deemed the most famous and publicly influential living philosopher, he was also listed among the 100 most influential people in the world by Time in 2005. He is the author, co-author, editor or co-editor of over forty books. His book Animal liberation (1975) was translated into Spanish (Trotta, 1999) and twenty-three other languages. His Practical ethics (1979) appeared in eighteen languages and is among the 100 more important philosophical texts ever. In 2021, he received and donated the prestigious Berggruen $1,000,000 Prize.

In 1993, he co-edited with Paola Cavalieri the book The great ape project and cofounded the organization of the same name. In 1998, I started to collaborate with him in this organization, creating with Paco Cuéllar and Jesús Mosterín its Spanish branch. We have now co-authored Los derechos de los simios (Trotta, 2022) which sums up thirty years defending the great apes, and updates the 1993 book in view of the numerous legal, scientific, and philosophical developments that have taken place in this time.

In June, he visited Barcelona to present our book as well as the documentary Persona (no) humana and take part in the event Two days with Peter Singer at Pompeu Fabra University. This is the origin of this interview.

The Great Ape Project

Besides prohibiting biomedical research and private possession of great apes, what else do you think a Great Ape Law should contain? The creation of a large, state sanctuary, eventually open to all captive apes? Lori Marino, who I have recently interviewed in Mètode, will administer contraceptives to the whales of her sanctuary. She finds captive breeding of such intelligent animals unacceptable, because their offspring could never survive in the wild since captive groups have lost their culture. Now, Duni, a young, Spanish female gorilla, has just been taken to breed in Prague. Considering that a) captivity causes similar cultural loss, suffering, neural atrophy, and other pathologies in apes, b) zoos are worse than sanctuaries, and c) ape breeding typically entails the permanent separation of young females from their families, it seems we should also oppose it. Do you agree?

I agree that we should oppose breeding apes for zoos.  But I do not oppose it for sanctuaries that can provide the conditions that enable apes to live enjoyable, varied lives, in a social group suitable to their needs. You might ask: what is the difference between a zoo and a sanctuary? My answer is that the goal of a zoo is to entertain visitors (and in the better zoos, to educate them as well). In achieving that goal, there will inevitably be compromises with the well-being of the animals confined in the zoo. The goal of a sanctuary for animals is to provide an environment that is not only safe, but also one that gives its residents the best possible lives, within the limits of the resources available to the sanctuary. If visitors do come to observe the animals, that should not be allowed to interfere with the animals getting on with their lives in the manner that is best for them.

Zoo breeding also reduces incentives for conservation, creating the illusion of an acceptable plan b. But what if zoo breeding was a species’ only realistic survival chance?

I would hope that zoo breeding would not be a species’ only realistic survival chance, and that if a species is unable to live freely in its own habitat, the sanctuary alternative I just outlined would always be available. But if it really is not, despite the best efforts of all involved, I would permit breeding to avoid extinction, while arguing for the responsibility to provide the best possible conditions for all individual members of the species.

My reading about primates, evolution, animal cognition, and ethology to defend apes and other animals slightly changed my views on animals, and massively changed my views on humans and gender. What are the scientific readings that most influenced your views?

Going back a very long way, it was Jane Goodall’s In the shadow of man. On factory farming, Ruth Harrison’s Animal machines had a huge impact.  But there have been many other works since. Victoria Braithwaite’s Do fish feel pain? convinced me that we need to pay more attention to the vast quantity of suffering that humans inflict on fish.

Animal liberation

You are currently revising Animal liberation. What are the main updates?

It might be better to ask: what remains unchanged? All the factual material needs to be brought up to date – that includes my accounts of factory farming and of experimentation on animals– as well as taking a more global perspective, including what is happening in China now. The ethical arguments have changed less, but I do say something about topics such as the suffering of wild animals, which I treated far too cursorily in the previous edition. In that area, the work of the Spanish philosopher Óscar Horta has been influential, and also of your colleagues at Pompeu Fabra University, Catia Faria and Eze Páez. I am, in fact, currently reading the text of Faria’s very clear and persuasive forthcoming book, Animal ethics in the wild. In the new edition I also respond to some more recent objections to my views.

What do you think is the next thing the European Union should do regarding animal welfare?

Ban cages. I was pleased to see that the European Commission endorsed that in principle. Now all Europeans concerned for animals must work together to make sure that it happens.

Animal liberation discusses some horrific speciesist practices (rather than individuals), but today, speciesism, understood as «unjustified differential treatment of some species», has become an insult people call those they disagree with. Even you, Will Kymlicka, and other animal advocates have been called «speciesist». I imagine you neither intended not expected this…

I did not expect it, and speciesist should not be used just as a term of abuse; but if the effect is to have a serious discussion about what speciesism really is, and why it is objectionable, I am willing to have that discussion, of course.

«We are continually learning new things, and no generation has a monopoly on wisdom»

There are authors like Peter Vallentyne or Shelly Kagan who vehemently reject as speciesist any subjective partiality to our own species but then consider the interests of all persons as objectively more important than the comparable interests of nonpersons. Isn’t that worse?

It is not speciesist to take that position, because persons does not pick out a species. Some humans are not persons, and some nonhuman animals – the great apes, for example – are persons, or at least closer to being persons than, for example, anencephalic humans. If the claim is made that the interests of persons are objectively more important than the comparable interests of nonpersons, we can ask why that should be so, and then examine the reasons we are given.  So – and in contrast to those who simply assert that they care more about members of the species Homo sapiens than they do about any other sentient beings – the claims about objective differences can lead to a fruitful discussion. Nor should we assume that it is speciesist to argue that, for example, cognitive differences affect the kind of interests that sentient beings may have, and that some interests may be objectively more important than others. If those who make this argument are prepared to acknowledge that nonhumans who have these capacities to a high degree have interests that are objectively more important than the interests of humans who have these capacities to a lower degree, then that isn’t speciesist, because the preference for (most) humans would not be based on their species.

Some animals live in the moment with no mental contiguity, autobiographical recollections or plans, and in Animal liberation you discuss the question of what could be wrong with painlessly killing them and replacing them with other animals with equally happy lives. What is your current thinking on this matter?

When I wrote the previous editions of Animal liberation, I was a preference utilitarian, and I argued that it is more serious to kill a being when doing so thwarts the being’s preferences for the future.  Killing a being not capable of having such preferences, I argued, is less serious, and possibly not wrong at all, if the being can be replaced with another whose welfare, understood in terms of preference satisfaction, will be at least as good as that of the one killed. Today I am more inclined to favour hedonistic utilitarianism rather than preference utilitarianism. That means that whether killing a being is wrong depends on the extent to which the killing reduces happiness or pleasure, not only for the being killed, but for all others affected too. It is possible that this view will also lead to the conclusion that the killing of beings with higher cognitive capacities is typically more serious than the killing of beings lacking those capacities, because the former beings may have greater capacities for happiness or pleasure, and also because beings with higher capacities are more likely to know that others like them are being killed, and hence fear that they will be killed, which will affect their lives in a strongly negative way. I am still not sure what to think about the replaceability argument – that is, the idea that it is all right to kill an animal who is living a good life if the killing is painless and the animal will be replaced by another animal who will then have a good life, and would not have existed if killing the first one was not allowed. This argument is used to defend «humane farms» that give animals a good life and would not exist if they could not kill the animals they raise and sell their corpses. I am uncomfortable with this, and concerned about the impact it has on our attitudes to animals.  But taken in itself, is it wrong? Who is made worse off because of it?  For the animal, it is arguable that a short pleasant life is at least not worse than no life at all.

Some philosophers argue that we should minimize animal suffering with large-scale interventions in nature, even if this destroys biodiversity, wilderness, and nature itself. Others hold more pluralist views that recognize the value of environmental preservation as well as that of suffering reduction. Since you recognize only one value (pleasure or no-pain), will you also advocate the end of nature, if this was an effective route to minimize animal suffering?

That way of putting the question may suggest that I am a negative utilitarian – in other words, that I care only about minimizing suffering, and not about increasing happiness. So, to rephrase your question: would I advocate the end of nature if this was an effective route to maximize the net surplus of happiness over suffering – and not only for animals, but for all sentient beings, present and future? Then I will answer yes, because as you correctly point out, I do not think that environmental preservation is an intrinsic value. It is important, though, because of its consequences for the well-being of sentient beings. In our present state of knowledge, I favour environmental preservation because I believe that this «end of nature» scenario would have highly negative consequences.

Although Animal liberation is known as the animalist Bible, bibles tend not to get updated. What do you think are the most urgent updates other holy books need? Including meat and CO2 in the sin’s list? Gender equality and LGTBQ+ rights? Advocating redistribution and contraception?

That is an interesting question, but first I must say that I do not believe in Bibles, so I do not want Animal liberation to be thought of in that way. We are continually learning new things, and no generation has a monopoly on wisdom. Treating some ancient text as if it must be obeyed is a terrible idea. The texts commonly taken as sacred focus, naturally enough, on condemning acts that were seen as harmful to individuals and to society at the time when they were written. So, they have rules against maiming and killing, against stealing, and against sexual promiscuity, because in the absence of contraception they wanted to ensure that children would be cared for and looked after. But they also had rules against non-reproductive sex, because societies with few people were likely to be overpowered by those with more people. The rules were made by men, whose greater physical strength enabled them to dominate women, so these rules gave women a subordinate status. On the other hand, as your question indicates, these ancient societies did not have the ability to change the climate of our planet, so that did not fall under any of their rules. And while rules about helping others are prominent, these rules extended only to those with whom there was some kind of regular and mutually beneficial contact, not to distant strangers, because it was impossible to know about, or assist, people suffering from famines in far-off countries.

Photo: Jordi Play

Procreation ethics

My favorite philosopher, J. S. Mill, argued (already in 1848) that once there are sufficient people, there is no reason to keep on creating more and more, and also producing more and faster in order to feed them. Instead, we should adopt a stationary state of zero material or population growth and focus on redistribution. Has your recent work on the overpopulation taboo reached similar conclusions?    

Not exactly. I agree with the need to focus more on redistributing the means for living well, so that everyone can do so, but at least in theory, if there can be more people living happy lives, I see that as a good thing. I am troubled about the taboo on discussing population growth because those countries in which population is growing fastest are also among the world’s poorest countries, and it is going to be extremely difficult for them to provide an adequate standard of living for populations that are predicted to triple by the end of the century.

Natallie Evans discovered she had cancer when undergoing fertility treatment with partner J. He suggested fertilizing her six eggs with his sperm. She sought options that did not require J.’s future consent, but he reassured her that it would not be withdrawn. In the two years she needed to recover, J. left Evans for another woman, and ordered the destruction of all six embryos, obtaining the European Court of Human Rights support. I found this unjust as it was her last chance to conceive, he could have declined earlier and he harmed her rather than merely failed to benefit her. What is your view?

I agree with you that Evans had more at stake than J. did. There is no right to prevent a woman having a child merely because the child carries your genes.

J. got a second chance to change his mind for free. She did not. This also happens with the so-called male abortions. Two people have sex. She gets pregnant unintentionally. He says: I cannot force you to abort, but I will not give you a cent, family name, information, chance to meet as adults, nothing. When Lukasz Wybranczyk asked you about this case, your reply was that he has the right to do so, but that a good person would not do it. This surprised me. You hold neither a rights-based nor a virtue-based view. And why should men have, in addition to the right (that women also have) to decline sex (or embryo production, in Evans’ case) a right to a second chance to change their minds costlessly? If they lacked a legal right to engage in such wrongdoing, they will become more careful, kids will have fathers, etc. The likely consequences will be better. So why should they have this right?

You are correct that rights are not the foundation of my view. I should have made it clear that I was asking whether society should recognize that right. That question should be answered by considering if there would be better or worse consequences, if society were to recognize it. To give a better considered answer, I would need to know more about the case we are discussing. Did both partners know that, if they had sex, a pregnancy might result? If so, then it would be reasonable to say that the man cannot coerce woman to have an abortion, and should she decide not to end her pregnancy, he should share the costs of supporting the child and do what he can to make the child’s life a good one. Here I would say that the law may require him to do so. But suppose that the couple agreed that a pregnancy should be avoided, and used contraception that unexpectedly failed. Then the situation is that only the woman can carry out their joint undertaking of having sex without having a child together. Admittedly, once she is pregnant, that is not as simple as using contraception, but if she has access to safe and affordable abortion, and declines to use this way of avoiding the birth of the child, I do not think that the man should be compelled by law to support the child (although he would be a better person if he did so). A law requiring that a man in such a situation must support the child would be open to exploitation by a woman who wants a man to be involved in the support of their child, but he does not want to have a child. She may therefore pretend to be using contraception or to be infertile when she is not.

Antivaxxers and antimaskers endanger others, which is something in between killing them and merely letting them die. But some a) magnify the difference between killing and letting die, and b) insist that failure to vaccinate or wear mask is a merely omission. How will you challenge both?

The failure to vaccinate or wear a mask may be an omission but going out in public places without getting vaccinated or wearing a mask is an act, and it is an act that increases the risk that you will harm others.  Even if being unvaccinated does not increase the risk that you will spread the virus – which may be true with some variants – it does increase the risk that you will get seriously ill and require a bed in an ICU, which will mean that others with less urgent medical needs may not be able to have treatment, and are therefore more likely to die, so it still puts others at unnecessary risk of harm. As a consequentialist, I do not think the difference between killing and letting die is intrinsically important. Confusion about this arises because the distinction is relevant to our assessment of the agent. If you go out of your way to kill someone, that tells us something different (and, normally, worse) about you than if you let someone die by not supporting an effective charity that would have used your donation to save a person’s life. But someone ends up dead in both cases, so the consequences may be equally bad.

Finally, having accomplished so much in your life, do you have regrets about something you could not do, or wish you had omitted or expressed differently?

There are many things I wish I could have done, but there is never enough time to do everything you want to do. As for things that I wish I had omitted or expressed differently, you may have in mind some things I have said that have given rise to a lot of criticism. Perhaps you are thinking of my suggestion that parents should be able to choose euthanasia for their severely disabled infants, or of my acceptance of an invitation to write a review of a book about people having sex with animals. (In the review I raised the question why human-animal sexual contact is a crime if the animal is not harmed and is free to move away and avoid the contact.) I do not think either of these issues are anywhere near as important as the issues I raise in such books as Animal liberation or The life you can save. So, would it have been better if I had not written about disabled infants or sexual contact with animals? Perhaps it would have been better. If I had not written on those issues, I would have avoided some unpleasant moments, including occasions on which I was prevented from speaking. I would regret having expressed those views if I knew that I would then have influenced more people to act on the views expressed in Animal liberation or The life you can save. But I do not know if that is the case. It is also arguable that the opposition backfired. It made me a more controversial figure who got more media attention, and as a result, more people may have read my work, including Animal liberation and The life you can save. Since I do not really know, I do not regret having written about the topics I have mentioned. In addition, I have not been persuaded by any of the criticism I received that the ethical views I expressed are unsound, and I believe that, like everyone else, I should be free to put forward arguments for controversial positions.

© Mètode 2023 - 116. Moments of science - Volume 1 (2023)

ICREA researcher, co-director of the del UPF Center for Animal Ethics and president of the Great Ape Project-Spain.