with Spencer Greenberg
the podcast about ideas that matter

Episode 161: Where philosophy meets the real world (with Peter Singer)

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June 8, 2023

How have animal rights and the animal rights movement changed in the last few decades? How has the scale of animal product consumption grown relative to human population growth? On what principles ought animal ethics to be grounded? What features of human psychology enable humans to empathize with and dislike animal suffering and yet also eat animal products regularly? How does the agribusiness industry convince people to make choices that go against their own values? What are some simple changes people can make to their diets if they're not ready yet to go completely vegetarian or vegan but still want to be less responsible for animal suffering? What attitudes should vegetarians and vegans hold towards meat-eaters? When, if ever, is it possible to have done "enough", morally speaking? What are the things that matter intrinsically to humans and other sentient beings? What is the most complex organism that is apparently not conscious? Will we ever have the technology to scan someone's brain and measure how much pleasure or suffering they're experiencing? How uncertain should we be about moral uncertainty? What should we eat if it's eventually discovered that plants can suffer?

Peter Singer is a philosopher and the Ira W. DeCamp Professor of Bioethics in the University Center for Human Values at Princeton University. His work focuses on the ethics of human treatment of animals; he is often credited with starting the modern animal rights movement; and his writings have significantly influenced the development of the Effective Altruism movement. In 1971, Peter co-founded the Australian Federation of Animal Societies, now called Animals Australia, the country's largest and most effective animal organization; and in 2013, he founded The Life You Can Save, an organization named after his 2009 book, which aims to spread his ideas about why we should be doing much more to improve the lives of people living in extreme poverty and how we can best do this. In 2021, he received the Berggruen Prize for Philosophy and Culture for his "widely influential and intellectually rigorous work in reinvigorating utilitarianism as part of academic philosophy and as a force for change in the world". He has written, co-authored, edited, or co-edited more than 50 books, including Animal Liberation, The Life You Can Save, Practical Ethics, The Expanding Circle, Rethinking Life and Death, One World, The Ethics of What We Eat (with Jim Mason), and The Point of View of the Universe (with Katarzyna de Lazari-Radek); and his writings have been translated into more than 25 languages. Find out more about him at his website,, or follow him on Facebook, Twitter, or Instagram.

JOSH: Hello, and welcome to Clearer Thinking with Spencer Greenberg, the podcast about ideas that matter. I'm Josh Castle, the producer of the podcast, and I'm so glad you've joined us today. In this episode, Spencer speaks with Peter Singer about animal suffering, the perception and psychology of eating animals, and utilitarianism and resource distribution.

SPENCER: Peter, welcome.

PETER: Thank you, Spencer. It's good to be talking with you.

SPENCER: You, too. I think it's really no exaggeration to say that you're one of the most influential living philosophers. And you've actually had a really big impact on me. I first read one of your books in college. I read Animal Liberation and it really influenced my thinking about animals. And it's very, very appropriate for today, too, because I understand that you have a new edition coming out, Animal Liberation Now.

PETER: It's almost a new book, really, because it's over 30 years since it was last fully revised. And there's so much change that about half of the material in the book is new.

SPENCER: Oh, well, yeah. So let's start there, talking about Animal Liberation and how that field has changed, and how treatment of animals has changed, and then, we'll get into a whole bunch of other philosophy stuff towards the second half of the recording. So what has really changed that has caused you to rewrite so much of the book?

PETER: The book has, as you might remember, two descriptive chapters. One on the use of animals in research and the other on factory farming. And because it hadn't been updated since 1990, that was really seriously out of date. So people reading the book would find out what experiments were done on animals in the 1980s but that's not very relevant today. And in terms of factory farming, there are clearly a lot of things that have also changed. So those two chapters had to be fully updated. Factory farming is also more global now. So I had to take account of what China has been doing, which is not good, I have to say. And China is also a bigger player in research on animals, too. So that's there, it's more global. Climate change has come into decisions about what we eat. I wanted to bring that in and give it quite a bit of space. And then there's just the fact that there's now a strong animal movement. And a lot of people ask me, "What progress has been made? Have we made progress? Have we gone backwards?" So, I want to answer that question and highlight some of the positives that have occurred while certainly not downplaying the distance that still needs to be covered for us to be able to look honestly at what we're doing to animals and say, "Well, we've changed and we now give animals what they are due." We're just very far from that.

SPENCER: Right. So one factor is population growth. The more people that are on earth, the more animals are being eaten and being raised in factory farms, presumably. But if we kind of adjust for population growth, would you say that the treatment of animals has overall gotten better or worse?

PETER: If we're talking about numbers and we're talking globally, you'd have to say it's gotten worse, even allowing for population growth. Because if you look at just China, for example, their population has grown, of course, since the first edition of the book in 1975. But also China has become more prosperous. In general, it's a good thing that hundreds of millions of people who were living in poverty in China now have better lives. But those better lives have more disposable income, which means that they're eating more meat. Whereas, meat consumption in affluent countries has been fairly flat or close to it, and in a couple of cases actually has declined. In China, it's just like one of those hockey stick curves where it just goes up. And so even though there is a population growth, there's a lot more meat being consumed. And China is developing huge factory farms to cater for that demand. Multi-storey skyscraper-like buildings. There are 26-storey buildings in China that are just filled with pigs on every floor to meet the demand for pig products in China.

SPENCER: I imagine a lot of my listeners are familiar with some of the arguments around animal suffering and why factory farms are gonna be problematic. But maybe you just want to give just a very quick overview of why this could potentially be such a huge issue on a moral level?

PETER: I see it as an issue that is, in some ways, parallel to other huge moral issues that we're familiar with, such as racism and sexism. And when we look at those issues, we see that there has been a dominant group: Whites for racism and males for sexism. And they have used those who were outside that group for their own benefits and purposes. Most viciously, of course, in the case of slavery, but also in other ways. And the ways in which men have dominated women and given them few options but to do what the men wanted. And along with that domination and abuse have come an ideology, which the inner group is used to justify what it's doing. So the superiority of Whites over those of other races. The idea that it's natural for women to be subordinate to men. And I think there's a real pattern here that we, as humans as a whole, do this to other species. We are dominant over them. We have power over them. We use them, exploit them, and enslave them, you could say. We use their bodies, eat them, use their products like milk and eggs. And we use them as tools for research and/or take their furs from them, and kill them for that. So there is that clear usage. And there is also an ideology that justifies that. One example is the idea in Genesis that God gave us dominion over the animals and the interpretation of this as meaning we can do what we like with animals. And that's been very explicit for many centuries in the Christian tradition. And then, there are ideologies that they don't really feel. They can't think, they don't feel at all. I don't think many people believe that. But we still tend to downplay their feelings and their sensitivities and their social needs (if they're social animals) in order to avoid the cognitive dissonance when we know that we're using them in ways that are causing them to have miserable lives or to suffer extreme pain. And that is certainly the case with factory farming, with the use of animals in research, with a whole lot of other areas that we're making use of animals and killing animals, catching wild animals like bait fishing in absolutely vast quantities. So all of that is, I think, a form of speciesism, which is a term that I use to make that analogy with racism and sexism.

SPENCER: I can imagine when hearing you talk about that, some people might think that you're advocating not using them as a means to an end. But my understanding of your approach is that you're actually much more focused on the suffering and utility aspects of it rather than sort of, "Oh, we shouldn't use animals because they're not ours to control." Do you want to kind of unpacked a little bit like the perspective you're coming from?

PETER: Sure, that question goes fairly deeply into more underlying ethics. The idea that we must not use others as a means to our end is an idea that comes from Kant. Whereas I take my ethics more from the English utilitarian School of Jeremy Bentham, John Stuart Mill, and less well known, but I think more philosophically sharp, Henry Sidgwick. So you're right, for me what is important is the consequences of our actions and what those consequences do for the well-being of other sentient creatures; so what do we do in terms of producing pain, pleasure, misery, or happiness. And unfortunately, what we do to animals in vast numbers is overwhelmingly to make their lives miserable and often very painful, as well. And we do this for purposes that are in no way essential for us, arguably don't benefit us at all, but actually harm us in the long run in terms of health, in terms of the ecology and the climate of our planet. The major use of animals is actually harmful rather than beneficial. But we continue to do it without really giving the interest of the animals the kind of consideration that I believe we should.

SPENCER: I think one thing that's easy for people to overlook, if they've never looked into this area, is just the staggering quantities we're talking about. If we look at how bad the lives of many of these animals are in factory farms, and we multiply it by the number of animals, it's absolutely mind-blowing the amount of suffering being created. Do you want to say something about its scale?

PETER: Yes, absolutely. You're right. The scale is really difficult to conceive. Globally, humans raise and kill something like 200 billion vertebrate animals for food each year. The largest number of those are fish because of the growth of aquaculture. And fish are sentient beings. Aquaculture is completely unsuited to their needs. But even putting the fish aside, we have something like maybe 85 billion vertebrate land animals raised for food. Chicken are the majority of those. The United States alone produces something like 9 billion chickens per year. And just to give one example of the kind of suffering that occurs, these chickens have been specially bred to grow extremely fast. So fast that in some cases, their immature leg bones collapse under them. The birds collapse on the floor, unable to move to food or water. Now, because you have 20,000 to 30,000 birds in a single shed, there's no individual care for birds at all. And those birds who can no longer walk or move will just die of dehydration or starve to death. And then somebody might walk through the shed once a day and look for corpses and pick them up and throw them out. But the industry average for birds who die — as I said, these birds are very young when they are killed, they're about six to seven weeks old — over 5%, one in 20 of them, don't even make it to slaughter. So that's close to half a billion birds who actually suffer to death. They don't get taken to slaughter, which is supposedly quicker than collapsing and dying of thirst or starvation on the floor. But if you think of that, it's happening every day on a vast scale. More than a million birds are suffering to death every day in the United States under their factory farm system. And that just goes on and on. And most of the people who eat chicken don't even know about it.

SPENCER: I was 18 when I had my first reading in utilitarianism. I was reading Bentham and there was a line and paraphrase that was something like, "The question is not do animals reason, but do animals suffer?" And that line just struck me so hard. And I actually became a vegetarian that day because of just that idea, "Wait a minute. It doesn't matter how smart they are. It matters what they experience and what we're doing to them." And so, that really resonated with me. And then reading Animal Liberation a few years later kind of really consolidated that view for me. So, it was very impactful in my own life. But when I go around the world and talk to others who are sort of not steeped in these ideas, it's just so different from the way people are used to looking at it. It's somehow we go about our lives, allowing the suffering to exist all around us get so normalized, that it's just totally normal to go eat another creature and not think twice about it. So I'm curious to hear some of your thoughts on the psychology of eating animals, and sort of how people sort of, on the one hand, care about animal suffering — because I think most people actually think it's awful to hurt animals and think that it'd be horrible to kick a dog, it'd be horrible to kick a pig for no reason even — and yet, they go and eat animals every day. Which I think I totally understand because it's so normal to do but I'm curious to hear your thoughts.

PETER: Yeah. So just before I talk about psychology, I just want to say that I think it's really wonderful that something that Bentham wrote more than 200 years ago is still affecting people. It still affected you. You read it, and you decided to stop eating animals. That's a really powerful example of what philosophy can do. And it is a powerful statement. I agree, you've got it right. He's considering the idea that we are more intelligent than animals, that we use language and he says, "The question is not can they reason, nor can they talk, but can they suffer?" And that is the crucial question. And I repeat that in Animal Liberation. Now, what's the psychology of this is, as you say, if somebody walked past somebody who was kicking or hitting a dog in the street, they would be horrified. And they would do something to stop this. And we like to think of ourselves as being kind to animals. But the same people who would be horrified by seeing someone hitting a dog in the street, are eating cows, pigs, and chickens, which often suffer much more than a dog being hit in the street. So what is going on there? I think to some extent, there is an ignorance of (for example) the things that I just said about all of these half a billion chickens who suffer to death. And people don't know about that. But I also think that they don't really want to know about that because they don't look at it. When I tell people why I'm not eating animals and start to tell them about factory farming, they say things like, "Oh. Don't tell me, you'll spoil my dinner." When you think about it, it is really quite a horrible thing to say. But people say it quite calmly and cheerfully as if it's a reasonable thing to say. Essentially, it's saying, "If you give me this information, I may realize that I'm doing something horribly wrong, terribly unethical. And I don't want to know that. I'd rather just go on doing it." I don't generally compare what we do to animals with the Holocaust, but in this respect, the psychology is a little similar to those Germans who saw the Gestapo taking the Jews (their neighbors perhaps) away and didn't really want to know what was going to happen to them. Because if they did, they maybe would feel that they had to do something to try and stop it or protest. And that in Nazi, Germany would have been extremely dangerous, obviously. They could have been taken in by the Schutzstaffel themselves and imprisoned or killed. So in a way, those Germans who turned away from what the Nazis were doing to the Jews, actually had a stronger defense for not wanting to know about it than people who say, "Don't tell me, you might spoil my dinner," who aren't in any danger at all, except perhaps in the danger of deciding that they need to change what they eat. So that's part of the psychology of not wanting to disrupt your habits and what you're doing. Another part of it, which has been shown in interesting experiments, is that we tend to avoid the cognitive dissonance that we might get by thinking less about the capacities of the animals we eat. And this was demonstrated in an experiment in which psychologists invited students to come in to answer some questions in research. And when the students came in, they were given a whole lot of different questions. But some of the questions were about animals and what they thought of the capacities and intelligence of cows and pigs and other farmed animals. So the students answered that. And then they did other tasks for another hour or two, then they were told that lunch would be served. And they were randomly selected in two groups, one of which was told that they were going to be eating a beef hamburger for lunch. And the other was told that they're going to be eating salad and a plant based meal. But before they sat down to eat, they were asked to just go over and refresh some of those answers that they've given. The ones who had been told that they're going to be beef gave different answers to the questions about the capacities of cows and answers which were in the direction of reducing the intelligence and awareness of cows. Whereas, the ones who were expecting to eat no meat didn't change their answers in that respect. So it really showed in quite a neat way that we are uncomfortable with thinking that we're eating intelligent, sensitive beings with a range of emotional needs. And we try to tell ourselves that that isn't the case when we're sharply aware of the fact that we're about to eat them.

SPENCER: This is an interesting study. My experience has been, when people dig into this topic, they have this moment where it seems like their subconscious is projecting forward, "Wait a minute, if I keep going down this line of thinking, then I might have to give up something that I care about or feel like I'm a bad person, or feel guilty or something like this." And at that moment, there's sort of like a branching path. They can either come up with rationalizations to make themselves feel okay about it or they can cause this thing that they see as bad for themselves (like giving up a food they like or feeling guilty or whatever) and so, you can see why the mind is like, "Oh, wait. We can protect ourselves by rationalizing, by just looking away." Right?

PETER: Yes, that's right. I think that is the easiest ad for some people. Obviously, I don't think it's a good ad. And I expect that there is still some dissonance that is going on in them even if they've suppressed it. And I have to say that personally when I became a vegetarian more than 50 years ago, I found that satisfying, really, to have my values in harmony with my actions. And I enjoyed the switch to different kinds of foods. When I was in England at the time, I was a graduate student at Oxford, it really meant switching from British (or even more broadly Western European cuisine) to exploring the cuisines of other cultures. India obviously has a huge range of vegetarian dishes. China has quite a few as well. Middle Eastern dishes have a number of vegetarian dishes; everybody knows falafel. Italian, Mediterranean. I suppose that was the one that I had been eating most of before. But it was really fun exploring those cuisines, and I felt good. It felt a little lighter without the heaviness of meat as part of my main meals every day. So I didn't think it was a sacrifice. In fact, the biggest difficulty was explaining it to our friends and at that time, there were very few vegetarians. So some people thought that would somehow become Frankenstein. But in terms of the actual change, it was good. I think I really didn't benefit from it.

SPENCER: It's funny that after I became vegetarian, one day, I was walking down the street. And I'd been having trouble adjusting, I had no idea how to eat vegetarian. So I had no idea what I was doing. And I was struggling, and I was feeling hungry. And I ran into the only vegan that I knew at the time. And I was like, "Oh, my gosh, I'm so glad I ran into you. How do you do it? I feel hungry all the time." He's like, I feel hungry all the time, too. And I was like, "Oh, no. I've made a terrible mistake." But then it just turned out, I was just being an idiot [laughs]. I just needed to get a few basic things right. And I was like, "Oh. Actually, it's extremely easy to be a vegetarian if you just kind of spend a little time reading about it."

PETER: Yeah, that's right. I certainly feel good and don't feel hungry. You were lucky that, well, maybe this vegan friend wasn't particularly helpful, but when I didn't know any vegans when I became vegetarian, there were most people — in fact, I didn't understand what the word meant until somebody explained it to me — who was a vegetarian and said, "Ah, there are these people who actually don't even eat dairy products or eggs." And there's a British Vegan Society that was surprisingly founded in 1944. But it had, I think, 300 members, something like that. And my guess is that there weren't too many vegans, apart from those 300 people in Britain. So yeah, it was really a different world. And now I think it has gotten a lot easier for people to make that change. And there's a much greater variety of foods on the market. They're sold in every supermarket. When I decided to give up dairy milk and buy soy milk, I had to go to a special health food store to get it, you couldn't find it in any supermarket. That's a very different situation now.


SPENCER: I think the idea of a moral circle is very important here. And I know that's an idea that you talk about. And one thing that brings to mind for me, is the way that many human travesties that have been committed have involved putting other humans outside of our moral circle. So let's say the enemy tribe is outside the moral circle, so it's okay to kill them. Or the people over there in that other country are outside the moral circle, and you kill them. And same thing with animals. Many people will put animals outside that have that moral circle. But it doesn't have to be just animals, humans in history have put all kinds of different humans outside of their moral circle. And so, I'd love to hear some of your thoughts about where the moral circle comes in with animal treatment.

PETER: Yes, you're right. I think it is a continuation of a process that we can see that has been going on for a very long time. And that when humans lived as small tribes, I think that the general thinking is that we evolved living in groups of more than 150. And people's loyalties and commitments, their social ethics, were limited to members of that tribe. And that continued across with those who were living quite into the end of the 20th century. When I was about 18, I went to the highlands of New Guinea and there were people there who would not walk across the ridge of mountains into the next valley because those were different people and their lives might be in danger. So we have then expanded as we lived in larger communities. As we were able to travel more, as we developed states with some kinds of more enforcement of that, we expanded our concern to members of our nation or state. We eventually expanded beyond that to the idea of wealth and the Universal Declaration of Human Rights in the mid 20th century. The idea that all humans have rights. And many people thought that once we did that, then that was the end of this expanding circle, that all of the beings who had moral status were now included. But of course, I don't think that's the case. I think that we do need to push that circle wider and include all beings who are capable of feeling pleasure or pain, or beings who are conscious whose lives can go well or badly from their own subjective point of view. We're not justified in leaving them out. They have interest that it's just as bad if a cow, a pig, a horse, or a dog feels pain as if a human feels a similar amount of pain. Humans certainly have different interests. We have an interest in being educated. We have interests in listening to philosophical discussions, which animals don't. But where our interests are similar, like not suffering physical pain (but also a wider range of interests, too) then I think we should expand that moral circle and give equal consideration to the similar interests of all beings who are conscious.

SPENCER: It seems to me that the meat industry has a very important role to play in this whole thing. And that in many ways, it makes it easy for people to be in denial about harm they're causing. We get these advertisements about these happy cows eating happy grass. Every message is like, "Oh. It's not that bad." Actually I ran a survey asking people (just the general population in the US) about their views on animals. And what I found so interesting is how many people actually said they cared about animals, even about farm animals, and how wrong they thought it is to hurt farm animals. And yet the place where they diverged, from what a vegetarian would say, is that they thought that the animals they were eating were probably treated okay. So they're like, "No. It's not okay to hurt farm animals. But I'm not doing that by my actions." It seems to me that part of that is sort of just propaganda from the meat industry and sort of allowing people to take actions that are, in many cases, totally out of alignment with their own values. I think that most people, if they live in line with their own values, would try to avoid harming animals to a large degree in their lives.

PETER: Yeah, right. But of course, it's true that it is very unlikely to not be harming animals if they're eating meat. And they may have a picture of cows grazing on grass, which cows will do. Some cows will do. So beef cattle are initially raised on grass before being transported a very long distance to feedlots where they're not on grass. And they're being fattened on grain, because that makes them put on weight faster, come to market faster. And also produces that kind of marbling that Americans will pay more for, which is like veins of fat that are running through the meat. So their lives are not good. But the lives of cattle, who are at least outside and have a bit more space to walk around, are probably, in general, still significantly better than the lives of the animals who are inside all of their lives, which is 99.8% or something of chickens produced in America. Inside the vast majority of laying hens (hens who lay eggs) are confined inside, and a majority of them are still in very small wire cages, where they can't really even stretch their wings fully. And they can't escape other birds, who they're sharing their cage with, who might be more aggressive. And pigs, too, are inside all their lives, typically. And there are a lot of kinds of suffering that go on there that people don't ever even think about. For example with both the pigs and the chickens, as I said, they've been bred to grow extremely quickly. And to do that they've been bred to have huge appetites and to put on weight very fast. Now, that's their genetics. Now think how do those animals come into existence? Well, they have to have parents with the same genetics. But the parents have to live longer than the chickens and pigs who people eat, because they have to be sexually mature — and the pigs and chickens are slaughtered when they're young and not sexually mature — so you have these animals with huge appetites, wanting to eat very fast, wanting to eat a lot and will grow very fast, but they have to live long enough to be able to reproduce. And if they did eat what they wanted to eat, they would get so obese that many of them would die. Many of the chickens, for example, would collapse from heart attacks. And they might not be able to mate, either. They would be so obese that they might not be able to actually mate. So the solution to this for industrial agriculture is essentially to starve these animals: to feed them, for example, this standard thing called the skipper-day feeding pattern, which basically means you feed these chickens, that you've bred to have huge appetites, only every second day. You starve them one day out of two. And that causes other problems. You can read this in the [inaudible] journals. Sometimes these chickens will drink too much, and that can be bad for them. Because they're hungry, and they can't get food, they're just taking in a lot of water. What do you do, then? Well, you turn off the water. So then, they're hungry, as well as thirsty, because your only real objective is to get them to be able to live long enough to reproduce. And the same is true for the cows. In particular, the breeding cows will also be kept on rations that are far less than they would like to eat. So there's all these kinds of suffering that go on that a standard that those who work in this industry know about but the public is completely ignorant of.

SPENCER: So crazy to think that if there was a murder factory in your town, and you just knew it was there. You know people were being ground up into grinders. People would be up in arms and we wouldn't let that happen. And yet, we've created this sort of murder factory, this suffering machine that just is all around us, and we kind of just live our lives normally.

PETER: Yeah, that's right. Now, it's interesting that there are some states in the United States where citizens can initiate referenda. California is an example. And when animal advocates have put some of these forms of post-confinement of animals on the ballot — and therefore they had the chance to inform the public about it because it's something that is coming up at election time — they win in California, that ballots to give found animals more space. There was one when Obama was first elected president in 2008, it got more votes than Obama did in California. And of course, California is a very strongly Democrat state, and I think about 60 something percent, but the referendum on giving animals more space got even more. And in Massachusetts recently, it got 78%. So if you can get this before Americans and really explain to them what's going on, they will vote against it. But it's only about half or less than half of the states of the US where you can do that. And when it comes to other methods of politics, especially at the federal level, the agribusiness lobby is so powerful that you can't get changes through for farmed animals. And of course, in the states where factory farming is really big, like Iowa, Nebraska, North Carolina, you can't get anything through their state. Congress has it but the agribusiness lobby is just in complete control.

SPENCER: The way I approach eating in my own life right now is when I eat out, I'm vegan, and at home, I'm vegetarian, but the animal products I source, I try to source them from more humane sources, which is not perfect. But for me, that seems to be a pretty good balance. And I'm wondering for people who don't want to go vegan, what are some small changes that they can make that don't affect their life too much, that make a big difference to the animals, whether this was really low hanging fruit in terms of reducing suffering?

PETER: I think one kind of low hanging fruit that isn't the fruit, of course, is to try to get eggs from hens who are really allowed to range freely. And that's possible, although it's not as easy in the United States, as it is here where I am speaking to you now, in Australia. Because in Australia, we have eggs sold in supermarkets sorted into three categories. And they're labeled appropriately. Caged eggs, barn laid eggs — so they're indoors without a cage — and free-range. In free-range, they have to be outside the majority of the day. And there are limits on the stocking densities, how many birds you can have per hectare. But in fact, the free-range egg producers compete to have fewer hens per hectare, so I can walk into a store near me and there are eggs for sale, where it says 200 hens per hectare — the hectare is two and a half acres — so that's plenty of space. I think Canada's free-range. they would be allowed to have up to 10,000 hens per hectare (which I wouldn't think is a good situation) but if you're buying those that have some hundreds of hens per hectare, I think their hens have good lives while they're alive. Now once their rate of labor drops off, they will get killed. So they will have shorter lives than they would naturally. The males of the egg-laying breeds are killed instantly as soon as their sex. Although there is some work going on to try and actually detect sex, if you like the fetal stage when the chickens are still in the egg. And even there's other work to try to get hens to lay only female eggs, that seems to be possible too. So maybe they'll solve the problem of the chicks being male to [inaudible]. But I don't think they'll solve the problem of the hens being killed when the rate of lay drops off. So it's still not ideal, but I think we could say, "Look, the hens get a decent life. And I don't want to be completely vegan, so I'll have some eggs to eat." That's one of the kinds of low hanging fruit. There's a tiny number of dairies that don't separate the calves from their mothers. Because that's the standard thing. It's another thing people don't know, by the way, but if you buy dairy products, then you are buying products made from the milk of a mother, whose calf has been taken from her within hours of being born. And the bond between a cow and her calf is very strong. The cow will call for the calf. Oftentimes, that may go on for days, even for weeks. Some farmers have said when a cow pastures the place where the calf was taken away, they stop and look around and call for the calf. So it's really pretty heartbreaking when you think that milk involves that separation. And the calf, the male cows, will probably be raised to veal, or they may be killed at an early age. The females may be taken away and grown up as dairy cows. But as I was saying, I have just a tiny number of dairies that keep the cows with their mothers, and only take the surplus milk. But I believe that there was one in New England somewhere that I read that it closed, so I'm not sure if there still is. So that's actually probably not realistic. And of course, the milk is significantly more expensive. But I think the alternatives to dairy products are now very good. And I don't think you really need dairy milk. I guess the vegan cheeses are not that good yet, but they're improving all the time. And I'm hopeful to see that we are getting cellular milk. In other words, milk produced from the cells of milk that are grown, so that there's no cow involved. And if that happens, and is economically competitive with dairy milk, it could really put the entire dairy business out of business, which would be a very good thing not only for animal suffering, but for reducing greenhouse gasses as well because cows are major emitters of methane. So that is a future possibility, though it's not on the market yet. It's funny that some people say to me, when I talk about being vegetarian, "Oh, I've stopped eating red meat, but I still eat chicken or fish." And actually, I think from an animal suffering point of view, that's worse. They should go back to eating cows, because cows are much bigger. They're rather much more valuable animals. So they're not going to be treated as badly as chickens and fish will be treated. And when you eat the chickens and fish, there's many more of them that it takes to satisfy you, to provide you with those meals, than that makes a cow. So I think if you switch from eating beef to eating chickens and fish, you're actually causing more harm to animals than if you'd stayed with the cows. But you might be causing less harm to the climate.

SPENCER: Yeah, I remember a number of years ago, Julia Galef did an analysis of calories per life. And milk had the most calories per life, about 17 million. So you were causing the least death by drinking milk, with cheese as second, and beef after that. And then the worst was broiler chickens and then eggs from laying hens. But broiler chickens were by far the worst among the group.

PETER: Yes, and of course, that's per life. But I would be interested in if we can quantify that suffering: how much pain and what the quality of those lives were as well. And that would still make probably broiler chickens the worst and it would make eggs from caged hens around the worst as well. But I think it would make fish, particularly carnivorous fish raised in aquaculture or factory fish farms. So we talked about salmon. You don't only have the suffering of the salmon — who was trapped in a net and salmon, of course, famously have instincts to swim across the oceans and back again to breed — so they're trapped in a net and they're swimming in circles around the net. They're also often suffering from sea lice because they're very crowded, which would be an irritating, painful condition for them. But in addition, because they are carnivorous fish, they have to be fed other fish or fish pellets. And to provide that, the trawlers are going out into the oceans and scooping up vast quantities of low value fish that humans don't want to eat directly. And those fish are dying painful deaths, because there's no humane slaughter for those fish. They're suffocating to death, typically, or they're being crushed to death, because they're holed up in huge nets with thousands and thousands of other fish on top of them. And then they're being fed to the salmon. So that the salmon that you buy then, is actually responsible for, I think, something like 80 or 90 other fish that died. So if you're talking about the number of deaths that you're causing per calorie, farmed salmon is going to be pretty close to being the worst, as well as in terms of the amount of suffering.

SPENCER: When it comes to perception of vegetarians and vegans, I think it's fair to say a lot of people will have a negative reaction. They just sort of get this vibe that they're being judged. This holier than thou attitude. And I'm just kind of curious how you think about this, because when I meet people that eat animals, I really don't hold it against them at all. I don't judge them at all for it. And I think the reason for that is partly because I think that people can contribute to the world in different ways. And while I do think it'd be better if they didn't need animals, like they might be way more ethical to eat lots of other ways. And I know, I'm imperfect. And so I also know that we're just incredibly mimicking species where we copy each other. And I do that as well in other domains. And suddenly, I'm curious about what you think about meat eaters? Does it affect your opinion of them, and so on?

PETER: Well, I'm not quite as tolerant as you, I would have to say. I do judge them. I might not express that judgment, because that's not going to be helpful. But especially when people clearly know about some of these things that I've been talking about. I meet people who say, "Oh. I've read your book. I read animal liberation. I think it's horrible what we do to animals, but I just like eating meat." And sometimes, I have been out with people who know my views, and who will still order chicken and eat it. And I really think, what is the problem here? It's not so difficult to avoid eating those products that you know you're causing a lot of suffering. Now, some of them may be very good people and otherwise. Sure. And they may say, "Look, my issue is helping refugees or working for people in extreme poverty." Okay. I can still say, "Well, they're good people. They just have this kind of blind-spot." But there's a lot of people who are not doing any of those things either. And I think, in fact, people who are concerned about animals, and who are vegetarian or vegan because of that, typically are doing much more for other people as well. Certainly, that's true in the Effective Altruism movement. People I know, who are doing a lot for people in extreme poverty, for reducing risks of extinction, some people who have donated a kidney to a stranger, I think that vegetarians and vegans are much more likely to be doing those things than people who are not vegetarians and vegans.

SPENCER: A funny coincidence happened last week. I knew you're gonna come on the podcast this week and I was on YouTube and a video popped up that it was recommending to me, and it was about your philosophy. But the title of the video was something like "The Most Controversial Philosopher Who Says We're All Evil" or something like this. And I thought that it was really interesting that they were positioning your philosophy that way. Because I think that is a way to interpret your philosophy. But I'm wondering, I imagine that you wouldn't accept that framing of it. So I'm curious how you react to that?

PETER: I wouldn't use the word evil myself really, partly because it has religious connotations or some sort of greater depth. As you said, there are reasons why people don't do these things. We are a conformance species. A lot of people don't want to do something that's different from what their friends and family are doing. They don't want to feel that they'd be judging their friends and family who are doing things that are wrong. So I don't think they're basically evil. I do think that they're (I don't know) lacking moral backbone, I could say. Except that's a vertebrate thing to say as if it's better to have a back bone than to be an invertebrate. But yeah, I think they're lacking the resolve and to take steps to reduce the harm that they're inflicting on the world. So if you'd said that I'm a philosopher who thinks that most people fail to live ethical lives when they could do much better, that would be a better way of putting it than saying that I think most people are evil.

SPENCER: The question of "How bad are most people?" is where you draw the line, right? Everyone could do better. Everyone could be more ethical. Even the most ethical person could probably find some way to be more ethical. And I think this is something that bothers people about utilitarianism. This sort of, "What is enough?" It's just sort of an infinite burden.

PETER: Yeah, that's true. And I don't claim that I'm doing everything that I should be doing. I think I could be doing more in various respects, including in particular, living more simply and cheaply and using more of my earnings to help people in extreme poverty. So I'm certainly not claiming to be a saint or perfect or anything like that. The question is, what is enough? Well, you're right. That really to live up to everything that utilitarianism would say we ought to be doing is extremely demanding. But if we know that we're doing a lot better than most people in the community we're living in, I think we can take some solace in that. And we can say, "Look. I'm not a saint. But I'm doing reasonably well when I look around and I compare myself with others. I don't have to feel bad about myself anyway. It could be better. I don't have to feel bad about myself." So I think that's the kind of comparison that we might make. But I think we should certainly be doing something significant on major questions like our treatment of animals, which is something that most people are involved in every day. If they're not vegan, they're involved everyday in some sort of involvement in the way animals are treated. I think people who are middle class or above in affluent societies should be doing something significant to help people in extreme poverty. And again, just how much that means will depend on how much disposable income you have. I think we should all be concerned and be active about climate change. That's another huge unfolding issue. But that may be being politically active more than trying to get off the grid and not emit any fossil fuels at all, which certainly makes life very difficult.

SPENCER: Now, I wanted to ask you more about your philosophy. My understanding is that you used to identify as a Preference Utilitarian. And now, I'm not quite sure if the right word is a hedonic utilitarian or classic utilitarian. How would you describe your current views?

PETER: Well, I consider myself a hedonistic utilitarian. It is the term I would use. But classical utilitarian is fine because the classical utilitarians, the ones I mentioned earlier (Bentham, Mill, and Sidgwick) were all hedonistic utilitarians, or said they were anyway. With John Stuart Mill, there's something he said which I don't think is compatible with being a hedonistic utilitarian but he thought he was. So, I did make this shift. And it was really connected with an even more fundamental shift that I made. Because early in my career as a philosopher, if you'd asked me, "Are there objective moral truths?" I would have said, "No. I don't think that there are." And I held a position that was derived from a professor who taught me at Oxford. He is R.M. Hare and the position was called universal prescriptivism. So he said moral judgments are prescriptions. They're like imperatives. They're things that we prescribe to ourselves: how we should act to others, how I should act. But we do it under a constraint. That's why they're universal prescriptions. Constraint of having to universalize and accept these prescriptions, even if we are the ones who would be harmed by them, rather than benefited. And that constraint Hare thought means that we end up with a kind of utilitarianism in which we should do what's going to satisfy people's preferences the most. Because we're putting ourselves in the position of everybody affected by our action, or even every animal affected by our action, and taking on their preferences, and then doing what we would most want to be if we were in that situation. So that was a view that I held for quite a while, for the first decade or two after I graduated. But I always have some doubts about it, particularly about why it is that you have to universalize? What's the basis for it? There's no objective truth in morality? Hare's answer was, "It's part of the meaning of the moral terms." So if I say, "You ought to do something." The word ought carries this idea that I'm using it in a universal sense. And I'm not, for example, an ego saying you want to do this because I'll be better off. Even if it would make you worse off, you still have to do it. And I didn't think that that idea that this is part of the meaning of moral language got you very far. Because you could always just say, "Well, I'll stop using ought." And I'll say, "Do this or do that." And then essentially, that's what Hare called amoralist. And he admitted that he had no real arguments to describe the amoralist, except perhaps prudential arguments that amoralists might not have a very good life if they don't act ethically or don't even pretend to be acting ethically. So that was a position I held. And gradually, I got persuaded that, in fact, Hare was wrong to deny that there are objective moral truths. And he was part of a kind of a wave in moral philosophy in the 50s. It started early with A.J. Ayer and his book Language, Truth, and Logic which was published in the 30s. But then it really took hold in English language philosophy in the postwar period, particularly in the 50s. It was called motivism. It was another non-objective sort of moral philosophy at that time. And Hare was part of that general school. And I came to think under the influence of philosophers like Thomas Nagel was one of them, and subsequently, Derek Parfit when he published his first two volumes of On What Matters. It was really a major work of our philosophy. I was persuaded that this was all a mistake, and that we can defend the idea of objective truths in ethics. And once I became persuaded of that, then I was no longer supporting Hare's view and the idea that we get more tomorrow's judgments by universalizing our preferences. It wasn't necessarily something that I would have needed to accept. I could accept a range of other views. And I could think about the things that are objectively valuable and what things are not objectively valuable. And I reread Sidgwick. I co-authored with a Polish philosopher Kataryzna de Lazari-Radek a book called The Point Of View Of The Universe, which is a phrase from Sidgwick, and which in some sense resembles his idea of universalizability, but on the basis of there being self-evident objective truths in ethics. And I came to accept that idea. And that pain is something that is objectively bad. It's objectively bad for pain to be inflicted on any sentient being capable of feeling pain, unless there is some justification such as this will cause less pain overall or cause so much pleasure and happiness, that it will be outweighed by that. So pain is something objectively bad, pleasure is something objectively good. You could also use terms like happiness and misery to show that we're not just talking about physical pains and pleasures. That became the basis of my utilitarianism. I was still a utilitarian, but going back more, as you said, to that classical version of utilitarianism, rather than to the more 20th century version that maximizes preferences.


SPENCER: If we look at what humans value, it seems that they value a lot more things other than just pleasure and pain, or even generalized versions of those like well-being. What convinced you or convinces you that those are the only two things that matter or the only thing that matters?

PETER: I suddenly think that there are other things that matter. But I think they matter instrumentally rather than physically. So I think that justice, fairness, and knowledge are good things. But when I asked myself, suppose that someone commits something that is unjust, but in doing so, they prevent some pain or suffering and there are no other consequences for any conscious beings. So injustice doesn't set an example that leads more people to be unjust. It doesn't lead to resentment that somebody says, "Hey, you dealt with me unjustly. That's bad and I feel humiliated by that, or I feel that you don't consider me or respect me." You put aside all of those things, and ask yourself, just the fact that this injustice has been committed. Perhaps, it's an injustice that nobody even knows about. And the consequences of this injustice are there is less suffering and more happiness in the world. Why is it wrong to commit that injustice? I can't say that it was. I can see why you would think that it was, unless you're being misled by the idea that, normally, we want to promote justice because it does lead to better consequences. And you're not sufficiently able to separate that 'normally, justice is a good thing' from the fact that this is a special situation in which you've been told that the injustice has no bad consequences and only good consequences.

SPENCER: With that justice example, I find that fairly convincing. But at least from my own perspective, I don't find it convincing for all these different thought experiments. For example, if we imagine one world with ten utilities but one person has all that utility versus another world where the utility is spread more equally between people but there is slightly less total utility. There's 9.99 units instead of 10. My brain says, "Oh. It's actually better to sacrifice a little bit of utility if you can spread it around, rather than just have one being have all the utility." And I think that I'm in the majority on that thought experiment, and most people have that intuition. So yeah, I'm curious about a thought experiment like that. What's your reaction?

PETER: Well, I think you're also being misled or most people are. I can't speak for you. Because normally, spreading resources more equally does produce greater utility. So I'm an egalitarian. In that sense, I would like to see more redistribution to those who are worse off. Especially when we think about this globally, it seems to me very obvious that when we have 700 million people in the world who are living on less than currently $2.15 per day (as the World Bank's standard of extreme poverty) and then you have other people who are earning over $100,000. It's pretty obvious that if you took the $1,000 from the person who's earning $100,000 and they now only have $99,000 and you gave it to the person who is living on less than $1,000 a year, you would make a much bigger improvement in their well-being, than you would cause harm to the person who now only had $99,000 rather than $100,000. And I think we tend to think about that when you describe these situations about more equal distribution. We tend to think that a more equal distribution will actually make people better off. And the situation in which one person is on 10 and the other people are on zero or something very low is one where we could increase utility by redistributing something from the person who has 10. So the example is a kind of curious one, where you're asking people to bracket that off and not think about that in terms of resources but thinking about it in terms of actual experienced happiness. And I think that's pretty difficult to think about. It's even difficult to think about what it would be for somebody to have this very high level of happiness and it not be based on something that could be distributed to someone else and make them better off.

SPENCER: I totally agree that it's very easy to kind of fall for that mistake with that thought experiment. But I think there are ways to concretize it that, at least to me, make me feel the same way. Imagine you have to distribute a bunch of electric shocks. Does everyone get a small electric shock? Or does one person get a huge electric shock? And I think most people's feelings are like, "Well. It's actually better to distribute it more equally." And that's even true, if the total amount of electric shock is slightly greater in some, they're willing to sacrifice at least a little bit of the utility to spread equally. And I do think that when I tried to be careful about that experiment. I do think I come to the conclusion that I value equality a nonzero amount. And so I wonder, do we just have to have different intuitions here, or do you think there's an argument like, one's making a mistake to value equality?

PETER: I think we do have different intuitions. I'm not sure that I would say that you're making a mistake if you differ from me. It's possible that you're not. And I don't think that I can really prove my view to you. I think the kind of example that you just gave there is a little bit like sometimes people say, "You have a choice between a million people having slight headaches, or one person being in real agony." I think that raises questions about what is the scale in terms of how we compare those different things? Now, because people don't just want to maximize utility or minimize suffering. They will say, "Well. There's no number of slight headaches that could justify leaving one person in agony, because they just aren't qualitatively different." I'm not sure about that. I think the number has to be very large, because I think the scale of the kinds of pains that people have is one in which you can get very far from the neutral point. If you have a neutral point where you're not in any headache, and then you just move a tiny bit. So yes, you've got a headache but it's very close to being in the neutral point. And then I think the scale goes a long way into the negatives, when you're talking about people really being in agony. I think, incidentally, the negative scale goes further than the positive scale. So I think the difference between being in extreme agony and being at the neutral point is greater than the difference between being at the neutral point and being as happy or blissful (or whatever) as any human can possibly be. So that's part of what's going on there. And then you have to say, "Well, suppose it takes 10 billion slight headaches to one person suffering extreme agony." Can we really imagine that? Do we have the capacity to submit what we are saying with that? With animals, we can't grasp the fact that there are nearly 10 billion chickens that are living in horrible conditions. And can we grasp the fact that there's a 10 billion population estimate whether that is better or worse than one person being in agony?

SPENCER: Yeah, it's a really good point. I mean, there's so many biases that kick in when we try to think about these things and make it really difficult, like scope insensitivity. We just can't understand the magnitude of 1000 people suffering versus 10 people suffering. Our minds just really were not built to deal with these kinds of things. But just to tell you a little bit of my story. So I identified as a utilitarian when I was younger. And then eventually, what started happening for me is I started thinking, "Why do I actually believe in objective moral truth?" And it came down to the fact that I really felt like some things are objectively morally true, and some things are not. And that was really at the core of my belief (just this feeling). But then as I thought about it more, I started thinking, "Well, wouldn't I feel that way exactly as much if, in fact, all objective moral truth was something that is an evolved mechanism that helped our ancestors survive?" In other words, we have these moral intuitions because they're really useful for survival. And that's why they evolved through hundreds of thousands of years. And that's why I have this feeling. And then as I thought about that more. I started thinking, "Yeah. Maybe, I don't have a really strong argument that it's objective, even though it feels so compelling for me internally." So I'm curious how you kind of think about where evolution fits into your perspective. If these moral intuitions did evolve, why would they evolve to sort of match what's objectively true about the world, if that makes sense?

PETER: Yes. And I think the answer is that they wouldn't necessarily evolve to tell us what's objectively true about the world. And to me, the evolutionary explanation of intuitions tends to discredit them, not to confirm them as intuitions that we want to believe and accept. Philosophers call this evolutionary debunking of certain views. Let me give you one example, which comes from Jonathan Haidt. He tells a story about an adult brother and sister — if I remember rightly, they are called Mark and Julie — and they're having a holiday together in a remote cabin with nobody else around. And they decided, just for fun, that it would be interesting if they were to have sex. So Julie is on the contraceptive pill, but just to make sure that there's no pregnancy resulting, Mark uses a condom as well. They have sex. They enjoy it but they decided that they won't continue and repeat it because it will interfere with their sibling relationship or something of that sort. So there was simply this one episode which they enjoyed and had no other consequences. Now you tell this story to a group of people — or this is what Jonathan Haidt reports, a group of students — and you asked them, "Was what Julie and Mark did wrong?" And the majority of them say, "Yes, it was wrong." And then you ask them, "So why was it wrong?" And they experienced what Haidt called moral dumbfounding. They can't really give any reasons why it was wrong. They just have this intuition, "Yuck! Brother and sister. Adult brother and sister having sex, yuck!" Or sometimes they come up with things that are ruled out by the story such as, "Well, they might have a child who would be abnormal," but we know they wouldn't have had child members. I think that's a good example of an intuition that ought to be debunked. So the intuition that it's wrong for a brother and sister to have sex in circumstances where there's no harmful consequences and conception can take place, I think we should reject that intuition. Even though I may actually feel it myself if I think about such a situation, because that's something that I believe evolved because there is a higher chance of abnormalities, and it was better for the survival of your offspring if you didn't have sex in the pre-contraceptive age with a sibling. So I think that there are a number of intuitions like that that can be debunked, but not all. And this goes back to the work that Kataryzna de Lazari-Radek and I did on Sedgwick in The Point of View of the Universe, where we discuss these arguments. And we bring them to bear on a problem that Sedgwick called the profoundest problem of moral philosophy, which is the conflict between egoism and universal benevolence. So utilitarians are universally benevolent in that they want the good of everyone. That's at least what the theory says they ought to be aiming at. Whereas egoists are interested in promoting their own good. And in Sidgwick, in his masterwork The Methods of Ethics, was examining egoism and utilitarianism, as well as the third method called Common Sense Morality, which is a kind of intuitionism. By the end of the book, he thought that he could show that this common sense morality was not a defensible ethical view. That in fact, it's the kind of indirect form of utilitarianism, a bit like what we were saying before that justice is not intrinsically good, but is beneficial because of its good consequences. But Sidgwick was not really able to resolve the opposition between egoism and utilitarianism, because he thought that there is a kind of — although he thought that universal benevolence is something that you can argue for as being self-evident, that is — the idea that the similar interests of anybody else should be given equal weight to my own interests, at the same time, he also felt that he couldn't really reject the intuition behind egoism, which is somehow that I have reason to be especially concerned about my interests, that I do not have to be concerned about the interests of everybody else. But if we bring the evolutionary story to bear, then I think we can see that the intuition-egoism does have an evolutionary explanation that is beings who care first and foremost about their own interests, and then perhaps about the interests of their offspring, more likely to survive and more likely to leave offspring who themselves survive and get to reproduce, than if they cared equally about the interest of strangers. So I think the intuition that so troubled Sedgwick behind egoism can be debunked as the product of evolution. And that leaves the utilitarian idea, or universal benevolence idea, as an intuition that is not to be explained by evolution, and rather is something that we can see having developed a certain level of reason. We can simply see that there's nothing special about my interests that mean that they should weigh more than the interests of others. I can take that broader point of view, that point of view of the universe, in which I kind of detach myself from my own interests and look down on the interests of all and say, "Yes. Those people who are capable of suffering just as I am shouldn't make them suffer, even if there is some benefit to me that is really less than their suffering."

SPENCER: Before we wrap up, would you be up for doing a quick rapid fire round where I ask you some short but difficult questions and just get your quick response?

PETER: I'm happy to do that.

SPENCER: Fantastic. All right. So first rapid fire question. Do you think that if we were to ever encounter technologically advanced aliens, there's a decent chance they might have also invented utilitarianism?

PETER: Yes, I do. I think that these basic truths would be reached by any rational beings who were also capable of pain and pleasure.

SPENCER: One thing I think is really admirable about you is the way you speak your mind. You say what you think is true, even if people get upset, even if people think you're a monster. But do you believe you're doing the right thing, and so you say it because it's what you think is good. And I'm wondering, has your view on this change at all on just the pragmatic value of being controversial? Would you kind of have done things differently if you knew how controversial some of yours would be, would you have done it the same way, in retrospect?

PETER: I think I would have done it the same way. Some people have told me that I shouldn't have said some of the more controversial things that I've said, because I tend to get more opposition for that. And the things that these people then agree with, like my views about animals and global poverty, would have been more widely accepted. But firstly, I'm not really sure whether that's true, in fact. And secondly, I think it's important as a philosopher to say what you think is true, and not to try to pull away from the consequences of your views. And utilitarianism does have these consequences that shock a lot of people in some circumstances. But I think that it's educational for people to see that these are the implications, but that one doesn't have to shy away from that. One can bite the bullet and say, "Yes, that's the way it is. And that's what I believe."

SPENCER: Are there examples where you felt you were wrong about the implications of your own belief system? And then now, in retrospect, you would have had to come to a different conclusion about what utilitarianism implies?

PETER: So I struggled with the question that half is discussed and raised about whether it's better to have a larger population of people whose average well-being is lower. But whether there's a greater total amount of well being in the universe, because the population is larger. When I first encountered that, which was when I was a graduate student at Oxford because Patrick was giving classes on that in the early 1970s — although he didn't publish on until much later — I thought that that was wrong. I tried to argue that we should be concerned with the well-being of those who exist or will exist in future rather than those who might possibly exist if we choose to bring them into existence or if we change policies so that other people will bring them into existence. But I now think that my early views on that were wrong. Halford himself wrote a devastating reply to one thing that I wrote, and I don't accept it anymore. But I still find the problem baffling. And I don't have a really clear view on what is the right answer for those questions.

SPENCER: Maybe a young philosopher that is listening will say, "Saw that."

PETER: Others have tried. I have to warn this young philosopher that there are many, many have tried.

SPENCER: So, imagine that one day, there's a super intelligence that could remake the whole universe into the perfect utilitarian universe. I'm wondering what your intuition says about what that looks like? Is that like, tiny, miniature algorithms that are orgasming at all moments, or some giant single mind that's perfectly happy or something else?

PETER: I want to say something else. But it's hard to say what it is. I do think that it would be a world in which there wasn't pain. If the super intelligent could design it so that well-being and happiness was maximized without any pain. Some people say you need to have some contrast to appreciate the good things. But if we assume super intelligence could design it, so that wasn't the case, then that would be good. But would it just be the pleasure of the super orgasms? Or would the pleasures of enjoying great literature and the company of other people and, for that matter, the pleasure of thinking through philosophical questions and being stimulated to think deeply about big issues? To me, that's one of the great pleasures of the world along with those orgasms. So I don't know. I suppose super intelligence could quantify and say, "No. Super orgasms are better than the pleasures of discussing the ultimate nature of the universe." Or maybe vice versa. Super intelligent would allow us to be discussing these deep questions because the pleasure would be greater. But let's suppose it came out in the qualification in favor of the super orgasms, would I just accept that that's the best possible world? Again, if I have to bite the bullet on that, I suppose I have to say, yes it would. I tap into that hypothetical case, I can't deny that that would be the best possible world based on my hedonistic utilitarian outlook.

SPENCER: Well, you certainly bit a bullet there. Nobody can deny that. What is the most complex organism that you think is probably not conscious? So here, of course, by conscious we mean is able to have experiences of any type.

PETER: Yeah. Probably there are some invertebrates that are complex but not able to have experiences. I think at the moment, a reasonable place to draw the line is to say that there are some invertebrates that can feel pain. Octopus is a good example. There's good evidence that lobsters and crabs can feel pain. But there may be some other complex invertebrates that can't. But it's really hard to be sure, because it's possible that bees, for example, are conscious. Again, complex behavior. They communicate the distance and direction of sources of pollen by performing the famous waggle dance. So I couldn't really name one, but I assume that there is a point at which you still have a certain amount of complexity without consciousness. And of course, we know more about the complexity of plants now. So maybe there are trees that are complex organisms but are not conscious.

SPENCER: Would that be horrifying if it turns out plants were conscious? Oh, my god. What a disaster it would be.

PETER: Yeah, it wouldn't be a problem. But it wouldn't actually be a reason for eating meat, because the animals who we would be eating would have consumed far more plants than we would consume if we ate the plants directly. So I don't know how much it would change.

SPENCER: Okay, just a few more for you. So, suppose there was a movement society to genetically engineer people to suffer less. So that you're born with genes that make them happier and feel less pain. Would you be in support of that?


SPENCER: That's easy [laughs].

PETER: It's a very rapid answer.

SPENCER: Do you think in theory that a device could be built that could scan someone's brain and measure how much utility they're experiencing? Even if [inaudible] technology, do you think that could be done, in theory?

PETER: In theory, yes. How you would verify that this was actually what it was doing, and it could detect who was suffering more than who less. It would be difficult because we don't have that direct experience of the subject of consciousness of others. But possibly one day, we could break out our brain so that we kind of put our own brain on hold and channel the experiences of someone else. And then we could say, "Oh, wow. You're much more sensitive to the dentist drilling the nerve in your teeth than I am," for example. So yeah, it's possible that we could do that.

SPENCER: Some people argue that you should be morally uncertain. In other words, you should assign probabilities to different moral theories and kind of act in a way that sort of takes into account those probabilities. But it seems like you kind of go all-in in utilitarianism. So I'm wondering what you think about moral uncertainty.

PETER: I think there are good arguments for saying that we should be uncertain about some things and take that into account in our decisions. I am pretty all-in about utilitarianism, but it's possible that I could be wrong. And if someone will say to me, "Look. Suppose you're wrong, then what you're doing here is really bad and/or what you're advocating is bad. And that would outweigh the benefits of you being right." I don't really reject those arguments. What's less clear is how the calculations are going to come out, and what kind of balance of the uncertainty plus the degree of confidence I have in my own utilitarianism, what that would lead me to do that's different from what I'm doing now.

SPENCER: A final question for you. Many people in the Effective Altruism community are very concerned about risks from AI. And they worry that advanced AI could destroy the world or could cause some really, really bad outcomes. I'm wondering, where do you rank AI in your list of world priorities among things like global health and to help animals, and so on?

PETER: It certainly ranks. Extinction risks, in general, rank. And AI is one of those extinction risks, super intelligent AI. But we also have to consider to what extent we can be confident that anything we do now will actually reduce the extinction risk. And compare that with other things where we can have high confidence that we're doing good, like reducing the suffering of animals in factory farms or assisting people in extreme poverty, or even working on more practical extinction risks where we have a better idea of what we need to do, like tracking large asteroids or comets that could collide with our planet, considering how we might detect them early enough to build rockets that would collide with them and deflect their path away from us. Those seem to be things that we could start doing now that might help us. I'm not sure that we're close enough to superintelligent artificial general intelligence, who really know how to reduce that risk. I think that it's possible that the work that people are doing now might turn out to be irrelevant when we actually try to do it. Which is not to say that I'm against people saying we should be thinking about this issue, we should perhaps be considering whether we should have a moratorium on advancing superintelligent AGI, although how we could get that moratorium to stick is another problem. So I'm glad that there are some very bright people thinking hard about these issues. I just don't think that this should be an issue that should dominate the Effective Altruism movement in a way that sometimes it comes close to doing or at least appears to be doing. I don't think in fact, it has dominated the movement, but it certainly has soaked up a lot of attention in the media and that's given that impression.

SPENCER: Peter, thank you so much for coming on. This is such a fun conversation.

PETER: Thank you very much, Spencer. It's been great talking to you.


JOSH: A listener asks: What would make the biggest difference in combating the bystander effect? Whenever I've heard of the bystander effect, it's normally in the context of physical danger. Like, you're on a boat and the boat is sinking, and everyone's just sort of standing around, like "What do we do?" And no one's taking charge and that kind of thing. But I think this person is also asking about cases like injustice or abuse or things like that, where there are just bystanders?

SPENCER: Yeah. If you think about it, why do people not always act when something bad is happening? Let's say, there's a crisis where someone is hurt and nobody's doing anything. Or someone's known to be an abuser, and nobody seems to do anything about it. And I think there's a few different forces going on. One force is that most people look around to others to get their social cues. And here's what they had found or at least seem to find in some of the classic studies on this, where if you had actors that were doing nothing, then people would be less likely to, let's say, do something about the smoke coming through under the door. Because they kind of looked around and said, "Oh, well, they don't seem to be freaking out. So maybe it's no big deal." So we kind of look to others for our cues. And this suggests that one thing you can do is you can be the one who actually acts, because if you go and say, "Hey, there's smoke coming in the door, what does that mean?" Then that can spur others into action. Whereas, if you sit there just looking around not doing anything, maybe others look at you and say, "Oh, well. They're not doing anything. Maybe it's fine." So that's one piece. Another piece is people worry about social rejection, or they worry about retaliation, so on. So, if there's an abuser in the community, it's one thing if the abuser is really low status. It's another thing if the abuser is high status or even a leader. But then the question is who's willing to challenge this person? Or what can you do? Because this person may be able to retaliate if you call them out. And I think they're often the best solution is power in numbers. So maybe the person has high status. But still, if you get a bunch of people together, all acting in a coordinated way, you can still fight against them. It's very hard to do it if you're much lower on the totem pole. It's very hard to do it one-on-one, if they are of much higher status in this hierarchy than you. People may side with them, and they may not believe you. Especially if the person is willing to lie, spread rumors about you to take you down. But if you can get three other people that were also abused by them and the four of you work together, there's a very high probability that you can depose that person. So I think that's something to think about.




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