Not a Meat Eater FAQ

There's an element of preaching to the choir in posting this here, and of course dietary choice seems much less important than choices around where to donate. But I still think this FAQ, which is really more of a Q, could be of interest to EAF users.

Preamble

Why did you write this FAQ?

I wrote this FAQ to explain why I think it is the case that animals raised for food suffer a lot, and why, as a result, people oughtn't to eat meat. Others have written similar things, but I wanted to explain my own reasons for not eating meat. Some people think eating meat is bad because it causes greenhouse gas emissions. Others avoid meat for health reasons. Personally, I would not eat meat even if it turned out that eating meat helped fight climate change.^[1]

(That said, as I'll discuss later, I also think actions other than going vegetarian or vegan can have even greater impact. For example, donating to effective animal charities often does more good, and eliminating factory-farmed eggs reduces more suffering than eliminating beef. I don't claim that vegetarianism is the best thing one can do for animals, only that it is very good compared to doing nothing.)

If I'm right about the suffering of factory-farmed animals -- and suspend your judgment on that point for now -- then what we're doing to those animals is one of the worst moral catastrophes in history, comparable to the worst instances of slavery, war and genocide. If so, it is an ongoing moral catastrophe affecting victims that cannot advocate for themselves.

Generally speaking, whenever we risk making a serious moral mistake, we should think it through carefully and honestly, just like those involved in the Atlantic Slave trade or the Great Leap Forward (or other risky endeavours that had more positive outcomes) should have thought carefully and honestly about what they were doing.^[2] But a lot of the arguments against vegetarianism that I see are weak, suggesting to me that most people have not thought carefully enough about eating meat. Even if one ultimately concludes that eating meat is fine, that decision should at least be grounded in solid evidence and reasoning.

Why should I read this if you're just trying to persuade me?

Clearly I'm not a neutral observer here. But I've made a lot of effort to let empirical facts and good-faith reasoning speak for themselves. And you stand to gain from reading this! The most obvious benefit is that you would be doing some of that necessary careful thinking I mentioned above. But also:

• You may be curious to find out what I think
• You may want to better understand why a vegetarian/vegan friend or relative might have made that choice
• You may want to find the part where you disagree with me
• You may be one of those rare people who just enjoy challenging their beliefs

In many ways, the deck is stacked in favour of eating meat. When someone first questions the morality of eating meat, they face multiple mental and social obstacles. First, they must admit that their previous behaviour has been wrong, a difficult thing. Second, they have to either change their attitude towards eating meat to one that disapproves of their behaviour, or change their actual behaviour, harder things still. And third, they may fear stigma, disapproval or awkwardness from telling others they no longer eat meat. (That is the case, at least, in many social settings, though not all.) These factors create psychological pressure to avoid seriously considering ethical issues around meat consumption.^[3] These considerations don't prove anything, but they are reasons to keep an open mind.

How is this FAQ organised?

The FAQ comprises ten sections:

1. A preamble (you are here)
2. The basic case for why I think eating meat is wrong
3. The natural and divine
4. The moral status of animals
5. Whether animals truly feel or experience things
6. Benefits humans can gain from eating meat
7. Benefits that animals can gain from being farmed
8. Whether an individual's meat consumption truly causes animal death and suffering
9. Possible disadvantages of vegetarianism
10. Implications following from the earlier sections

Why Think Eating Meat Is Wrong?

Why do you think eating meat is wrong?

Here's the argument in the fewest possible words:

1. Every day, hundreds of millions of farmed animals are killed, the majority of whom are factory-farmed (Ritchie 2023). In the US alone, around 10B farm animals are killed each year, an estimated 99% of which are factory-farmed (Ritchie 2023).
2. The lives of factory-farmed animals are characterised by deprivation, pain, suffering and boredom. At minimum, raising an animal for meat involves killing the animal as soon as it's grown to its full weight, which occurs when they are still very young compared to their natural life expectancy. Because these animals are very likely capable of feeling and perceiving pain, boredom and so on, their pain and suffering matters.
3. This state of affairs would hardly exist, or at least be greatly diminished, if it wasn't for people eating meat. Hence, it is wrong to eat meat.

Obviously many will dispute some of those claims. The first claim is empirical, while the second and third claims involve a combination of evidence and value judgments. The remainder of this FAQ will explore all three in more detail.

But first, let me expand a little on the staggering scale of factory farming. Each year, over 100B animals are killed for meat and other animal products (Ritchie 2023), about as many as the number of humans who have ever lived on Earth.^[4] Humans eat lots of different animals, from cows and pigs to dogs and horses and fish and whales and insects, but let us focus on the most commonly eaten land animals: cows, pigs and chickens. In the US, 33M cows, 130M pigs and 9.4B chicken are killed annually. That is 10%, 38% and 2,800% of the US human population (340M), respectively. In the EU, according to my estimates, 24M cows, 290M pigs and 9.3B chicken are slaughtered for meat annually.^[5] Most of these animals are raised in factory farms. In the US, 98% of pigs, 70% of cows, and 99.97% of chicken are factory-farmed (Ritchie 2023). The global number is likely lower, but still suggests a majority is factory-farmed; according to one estimate, about three quarters of global land livestock is factory-farmed. These numbers are fairly rough but the orders of magnitude are uncontroversial.

Ok, so why did you stop eating meat?

I stopped eating meat for the reasons I just outlined.

I ate meat for a little over 25 years, having grown up in a meat-eating household. I think I stopped in 2014 or 2015, so about a decade ago. But by then I had already for some time arrived at the conclusion that eating meat was wrong. In fact, I looked through my email history just now and learned that I wrote, on 24 March 2012: "If I had any power of will I would be a vegetarian. But I'm too lazy and I like meat."

So at some point around or prior to 2012 I must have been persuaded that eating meat was wrong. I don't remember exactly what persuaded me, but I remember that it was the moral argument about animal welfare, not arguments around health or climate change, that persuaded me. I especially came to think that torturing animals in factory farms was bad and wrong. I did not overcome my laziness to become vegetarian until 2016 or so. In 2021, I became vegan.

Isn't "torture" a little extreme?

I'm using the word "torture" according to the dictionary definition: to "inflict severe pain or suffering on" or "cause great mental suffering or anxiety to" someone.

Animals on industrial farms are routinely confined to highly restrictive spaces that prevent them from walking, turning around or extending their limbs. In 2008, the Pew Charitable Trusts -- hardly an animal rights organisation -- published a report on US industrial farm animal production. The report was chaired by a former governor of Kansas who had previously been a dairy farmer and it concluded: "After reviewing the literature, visiting production facilities, and listening to producers themselves, the Commission believes that the most intensive confinement systems, such as restrictive veal crates, hog gestation pens, restrictive farrowing crates, and battery cages for poultry, all prevent the animal from a normal range of movement and constitute inhumane treatment."

These "most intensive confinement systems" are extremely common, especially in the US. Sows and chicken spend many weeks immobilized in body-sized cages, but even short periods are distressing. As one Auschwitz survivor put it (describing a standing cell):

It was a terrible state, as I thought that it was over for me, everything seemed so indifferent and distant to me. I couldn't lie down, I couldn't squat, the best thing was to stand, stand for six days and six nights. [...] With your elbows you touch the walls on both sides, with your back you touch the wall behind you, with your knees the wall in front of you. [...] This is no punishment or pre-trial detention, it is torture, straightforward medieval torture. I had bloodshot eyes, was stupefied by the bad air, and just waited for the end.

Animals in factory farms are routinely mutilated. For example, when pigs are overcrowded and deprived of stimulation, they sometimes bite each other's tails. The standard solution to this problem is to cut off the pig's tail when it is young (Sutherland and Tucker 2011). Male piglets are restrained and their testicles are cut out with a knife in order to avoid a bad smell ("boar taint") when cooked (De Briyne et al. 2016; von Borell et al. 2009). Chicken have parts of their beaks removed to prevent injury and cannibalisation (Kuenzel 2007). Calves have their horns cut off using clippers and hot irons (Gottardo et al. 2011).^[6] All these things are routine in the meat industry, often done without anesthesia or even painkillers, and rarely carried out by trained veterinarians. The pain they induce is most likely excruciating.

I don't trust those accounts of animal abuses. Sure, maybe some factory farms are that bad, but in most of them, animals are probably treated humanely?

If you are skeptical that anyone would treat animals like that, consider this very simple explanation. The meat industry's primary purpose is to generate shareholder value. There's nothing wrong with that as far as it goes, but it means there's strong pressure on companies to generate meat as cost-effectively as possible -- to reduce costs and maximise throughput. However, there are very few laws regulating the conditions of animals on factory farms -- in most places, the meat industry is free to do almost as it wants, so long as it is considered a necessary part of meat production.^[7] (In the EU, things are a bit better than elsewhere, with directives setting some minimum welfare standards and some countries banning some of the most unseemly practices.^[8]) As a result, the default outcome is that animal welfare concerns take a backseat in favour of cost reduction and efficiency.

This plot from Mekonnen et al. (2019) shows how animals now produce far more food than in the 20th century. A chicken born today contains twice as much meat as one born in 1960. A dairy cow born today produces three times as much milk as one born in 1960. In a way, this is good, because it means fewer animals need to go through factory farms to produce a given amount of meat. But it also involves placing more stress on the animal in a highly optimised system, as they are selectively bred and managed to grow extremely fast and to ever greater weights, causing lameness and other health issues (Clark, Potter, and Harding 2006).

Adding to those problems, farmed animals are often handled roughly and not unfrequently subjected to outright abuse. They're put in crowded, featureless environments depriving them of their natural behaviours. Their living spaces are unsanitary and disease-ridden -- for example, >500M chickens have been killed ("depopulated") to contain various avian influenza outbreaks between 2005 and 2024 (Al Awaidy, Asghar, and Zaraket 2024). They get injured and their injuries are often left untreated. Females are forcefully impregnated with rods. Piglets are weaned from their mothers at two to four weeks instead of the natural three to four months and dairy calves are separated within hours (compared to the natural weaning period of ten months) (Faccin et al. 2020; Lewis 2016). When transported to slaughterhouses, they are packed into crowded trucks and denied food and water for extended periods; according to one estimate, "20 million chickens, 330,000 pigs and 166,000 cattle are dead on arrival, or soon after, at abattoirs in the US every year [...] 800,000 pigs are calculated to be unable to walk on arrival". And so on. Again, these are just the natural consequences of a system designed to maximise cost-effectiveness with minimal oversight. There would be nothing wrong with this if it were not the case that the products are living animals.

(Benjamin Hilton has written an excellent essay describing conditions in factory farms in more detail, and quite even-handedly. Less even-handedly, the documentary Dominion has a lot of factory farm footage.)

You can't just tally billions of animals like that and conclude they are more important than a smaller number of humans. Aren't you assuming utilitarianism?

I think it is wrong to eat meat under any reasonable moral framework. That includes utilitarianism, deontology, virtue ethics, care ethics and plain common sense. Putting aside the empirical questions for a moment, all I assume here is that it is good and important to promote the general welfare. That view is compatible with utilitarianism, deontology, virtue ethics, care ethics and any other reasonable moral theory I can think of. You can find arguments for and against eating meat by philosophers of just about any school.^[9] Arguments against eating meat include Singer (1975) from utilitarianism, Regan (1983) and Korsgaard (2018) from deontology, Adams (1990) from feminist ethics and Scully (2002) from conservative Christian ethics. Even Roger Scruton, one of few philosophers who took up the position against animal rights, condemned factory farming: "Someone who was indifferent to the sight of pigs confined in batteries, who did not feel some instinctive need to pull down these walls and barriers and let in light and air, would have lost sight of what it is to be a living animal" (Scruton 1996).

Anyway, I mention the numbers because the numbers matter. Behind each number are many individual animals. When you see a number like "73,000,000,000 chickens slaughtered per year", it is only a number. But at the risk of stating the obvious, those are 73,000,000,000 individual chickens, each with its own mind and personality. Just like saving two human lives is better than saving one human life, if killing one animal is bad, then killing 73B animals is far worse. For a typical person in the West, a decade of vegetarianism could save something like 210-280 chickens, 4-6 pigs, 0.5-1 cows and many other farmed (and wild caught) animals.^[10]

How can you say eating meat is wrong according to common sense? Nearly everyone eats meat. Like, for many thousands of years the proportion of humans that have abstained from meat must have been well below 10%. Shouldn't we expect most people to be vegetarian if eating meat were truly so terrible?

I don't think most people have made a serious attempt at figuring out whether it is good or permissible to eat meat. Many vegetarians and vegans probably have, since most of them grew up as meat eaters, and they must have switched for some reason. But the majority of people grow up as and remain omnivores and probably never seriously consider whether eating meat is permissible -- as in, they may vaguely think about it once in a while, but don't sit down and run through the arguments the way we are doing here. (Very few omnivores grew up as vegetarians or vegans, so the reverse doesn't apply.)

People often unconsciously process information in a way that supports their pre-existing preferences or self-interest -- this is called motivated reasoning and is a widespread finding in psychology (Epley and Gilovich 2016). Since most people grow up eating meat, the way they seek evidence and evaluate arguments will tend to favour eating meat. The reverse is true of vegetarians and vegans, by the way, but most vegetarians and vegans have also at some point been on the other side. We can't assume that just because most people do a thing, it is morally justifiable. Slavery is not morally justifiable and was widespread for millennia of human history. Just as societies can cling to false empirical beliefs for centuries in the face of contrary evidence (e.g. heliocentrism), they can also persist in moral error for centuries.

God and Nature

Animals kill animals all the time. It's the natural state of things. The wolf kills the deer, the owl kills the field mouse and the lynx kills the hare. So why shouldn't the human kill the cow, the pig and the chicken?

If children constantly bully each other, does that make it fine to bully children? It's true that animals murder, rape, steal and destroy their offspring. But that does not automatically mean we are free to do all those things to the animals. (And it's worth noting that many commonly farmed animals, like cows, pigs and chicken tend not to kill and eat each other.) Animals do terrible things to each other because they cannot do otherwise. They just act instinctively. They lack the cognitive abilities needed to make moral judgments. We, on the other hand, do have those abilities and can act morally. And when we don't, we are blameworthy.

I think it's important not to mistake moral agency from moral standing. Moral standing is the right to have one's interests factored into others' moral choices, whereas moral agency is the ability to make moral choices. My claim, summarised in the table below, is that animals have moral standing, but not moral agency. (More on the moral status of animals later.)

Thing Moral standing Moral agency

Human Yes Yes

Pig Yes No

Rock No^[11] No

Didn't God give humans dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth?

I'm not religious, but from what I can tell, the Bible does not provide clear moral guidance when it comes to animals and factory farming, and so Christians can't rely solely on scripture for these ethical decisions -- they need to engage in independent moral reasoning. The "dominion" passage (Genesis 1:26) is probably the most important and action-guiding one. I haven't read Scully (2002) but I know it's written by a conservative and I gather it argues we should interpret the dominion passage as a call to stewardship, not a carte blanche to do whatever we want with animals. When humans are called on to rule over humans, that doesn't normally include a right to torture them.

It is true that various Biblical passages condone or depict meat eating, animal sacrifice and so on. For example, after the Flood, God gave Noah explicit permission to eat meat (Genesis 9:3): "Everything that lives and moves about will be food for you. Just as I gave you the green plants, I now give you everything." I suppose Adam and Eve were vegan initially, and Daniel and his companions chose a vegetarian diet for a while (Daniel 1:8-16), but as far as I know there are no ethical vegetarians in the Bible. But the Bible seems to condone and depict many practices that we now reject, like slavery, polygamy and capital punishment for minor offenses. It was written (or inspired) at a time that was extremely different from today, so we can't naively use it as a direct guide for contemporary moral issues like factory farming, especially since factory farms didn't even exist back then.

What's more, some Biblical passages offer guidance that seems incompatible with modern factory farming. For example, Proverbs 12:10 says "the righteous care for the needs of their animals". Exodus 20:10 says that, on the Sabbath, "you shall not do any work, neither you, nor your son or daughter, nor your male or female servant, nor your animals". In God's covenant with Noah after the Flood (Genesis 9:9-10), He includes "the birds, the livestock and all the wild animals ... every living creature on earth".

Would you also not eat lab-grown meat? That's meat, too -- at least according to you vegetarians and vegans. And what about roadkill -- would you say it's fine to eat that?

What matters to me are the experiences that animals live through, and the practices causing those experiences. I keep the rule "don't eat meat" because I find it simpler and easier to keep a simple rule, but I don't think it's necessarily always wrong to eat meat. Eating roadkill, eating lab-grown meat and eating meat when it is necessary for survival, all seem acceptable to me. I'm only saying that, for most people, and in most situations, the benefits of eating meat (that came from animals) are greatly outweighed by the harm it involves.

The Moral Status of Animals

How can we know that animals matter morally at all?

There is no certainty in ethics, but I think most ways we can justify caring about other humans' welfare also end up justifying caring about many species of animal (if perhaps to a lesser degree). In particular, most would agree that pain and suffering are intrinsically bad, and it seems irrelevant whether the pain or suffering is happening to a human or some other animal, so long as it is being consciously experienced.

I will discuss animal sentience (the capacity to perceive and feel) later, but for now, let me point out that I'm not arguing a minority position here -- there is widespread agreement that animals matter morally. Most countries have laws against animal cruelty, and many Western countries formally recognise non-human animal sentience.^[12] In fact, nearly everyone acts as if at least some animals do matter morally -- they just don't apply the belief consistently. The vast majority of people -- at least in modern societies^[13] -- consider it morally wrong to, say, douse cats in acid or punch dogs. Why would those actions be morally wrong if animals don't matter?

Kant argued that animal abuse is wrong only because it damages our own moral character. Maybe that is why we have those laws and reactions against animal abuse, and not because of the animals themselves?

I don't think so. When we oppose animal cruelty, we typically feel we do it because animals deserve protection for their own sake, not because being kind to animals makes us better people. My moral intuition, at least, tells me that an animal's pain matters directly, even if it does not affect human character. That is one common critique against Kant's argument. Another critique, which I came across in Korsgaard (2018), argues that Kant's reasoning is "almost incoherent". If we only care about animals because it ultimately helps us treat humans better, then we do not really care about the animals themselves -- we are only using them as tools for our own moral development. But that does not seem like an attitude Kant would want us to cultivate, since he also argued strongly that we should not treat moral patients (humans, in his view) as mere means.

I think there is some truth in Kant's reasoning: it is good for us to take a benevolent attitude towards sentient beings, because that makes it more likely that we make good moral decisions. If we acknowledge that animals can suffer and that this suffering matters enough to create indirect duties, we've already implicitly granted them some form of moral status that can't be coherently reduced to mere instrumental value for human character development. That is, why would torturing an animal be damaging to our moral character? The simplest explanation is: because torturing an animal is morally wrong. (For a more comprehensive summary and critique of Kant's reasoning on this question, see Korsgaard (2018).)

But even if Kant is right and animal abuse is wrong only indirectly due to its effect on us humans, that would still be a problem for factory farming. Because factory farming is a form of animal abuse and it is nothing if not human-caused.

Are you sure you're not just falling for anthropomorphic bias? How do you know your compassion for animals isn't a misfiring of caregiving instincts we have for infants?

I agree that anthropomorphism is a real phenomenon that can distort our intuitions on these questions. That is why I put a lot of weight on observable markers like animals' brain structure, their behaviour and our shared evolutionary history, more on which later. And as a result, I think there is good reason to also care about animals that are dissimilar to humans, like cephalopods, fishes and crustaceans, even though these are likely less sentient than cows, pigs and chickens.

Still, there is probably some accidental truth to anthropomorphism. Sentience probably exists on a spectrum, as a result of its having evolved gradually over millions of years.^[14] Since humans appear to possess the highest degree of sentience, it makes sense that our closest evolutionary relatives would be more sentient than distant ones. These closer relatives also tend to share more physical and behavioral traits with us.

Animals are much less intelligent than humans. Isn't that a reason to treat them differently from humans?

I do not have a good answer to this question, because I never understood why intelligence would matter when determining the moral status of animals, except as a correlate of factors that do matter, e.g. the capacity to experience pain. We certainly don't consider intelligence relevant when deciding the moral status of humans; ignoring any second-order effects, it is equally bad to inflict pain on a human with an IQ of 110 as it is on someone with an IQ of 90. Some humans are severely intellectually disabled -- enough to be less intelligent (for any reasonable definition of "intelligence") than some animals -- and yet their suffering matters too.

It is possible that greater intelligence unlocks some types of higher-complexity suffering. For example, Robert Oppenheimer probably suffered from the moral dilemma he faced in the development of the atomic bomb. That exact flavour of suffering is probably not available to chickens. (Or perhaps it is, and it is only the cause of the suffering that is unavailable to chickens.) But you could also imagine intelligence helping to alleviate suffering, for example, by allowing sophisticated mental coping strategies. I don't know what the net effect is. Either way, that still leaves the other animals with plenty of important varieties of suffering that are unlikely to require substantial intelligence, e.g. physical pain.

Okay, but severely intellectually disabled people are still members of the category of humans, doesn't that count for something?

That sounds arbitrary to me. What is it that makes "being human" morally relevant? Why draw the circle around "human" and not around "European" or "those who dream in black and white" or "mammal" for that matter? Suppose tomorrow scientists discovered a group of Neanderthals or Denisovans living in caves underground -- can we then do whatever we want to them because they are not members of H. sapiens, despite their possessing all the traits we associate with personhood? Species membership just doesn't seem like a morally relevant characteristic, especially compared to things like "capacity to suffer" and "having preferences", where the relationship to morality is obvious.^[15]

Animal Sentience and Consciousness

How can we possibly know that animals feel pain?

I am not saying that we can know animals feel pain. There is no certainty in sentience. How can you know other humans feel pain? They can tell you they feel pain, but there's always some chance they're lying or mistaken -- you have no access to their internal experience. You can only know that you feel pain and observe that other humans are similar to you in relevant ways.

Because we cannot know for sure whether the other animals can feel pain, we have to make decisions under uncertainty. So we need to find out how probable it is that animals feel pain (and so on), and then decide whether or not to eat meat with that probability in mind. Given how terrible conditions are in factory farms, and given that eating meat necessitates killing animals, we ought to avoid eating meat even if it's only somewhat likely that those animals feel pain.

Okay, then how can we be sure it's somewhat likely that animals feel pain?

Let's start with a shared premise:

1. It is almost certain that humans typically can feel pain.
2. Humans' ability to feel pain derives from certain structures in the brain and body.
3. Those structures evolved through natural selection, presumably because pain sensing conferred survival and reproductive advantages.

Humans and other animals have a long shared evolutionary history resulting in many common neurological features. For example, many animals have neural pathways (e.g. pain receptors) similar to ours that detect and respond to potentially damaging stimuli (Smith and Lewin 2009). There are also common brain regions (e.g. the amygdala and the anterior cingulate cortex) that show similar activation patterns in humans and other mammals when exposed to adverse stimuli (Hayes and Northoff 2011, 2012).

These similarities are borne out by behavioural studies (and common experience) showing that animals typically go to great lengths to avoid harmful stimuli, as you'd expect if they found pain unpleasant (Sneddon et al. 2014). For example, in one experiment, rats learned to push bedding in front of them as a protective shield when approaching shocking electrodes (Pinel, Mana, and Ward 1989). Animals' responses to harmful stimuli also change if you give them painkillers like opioids or NSAIDs (Fischer 2022). That is not just the result of painkillers reducing overall activity -- for example, when given the option to self-medicate, lame chickens will actively take more painkillers than healthy chickens (Whittaker and Howarth 2014; Danbury et al. 2000).

Maybe animals have pain responses without really being aware or conscious of pain?

Maybe. Sometimes when I am in pain for a longer period of time, the pain can fade from awareness as I get distracted by other things. But when my attention is called to the pain, I become aware of it again. A pain receptor firing (nociception) and triggering motor responses is different from the raw feel of pain -- the actual sensation that makes us want it to stop. So it seems fair to ask whether animals are in that state of unawareness constantly, only reflexively responding to negative stimuli?

I think the best approach for answering this question is, again, to look at evolutionary, neurological and behavioural parallels with humans. The behavioural evidence in particular seems hard to reconcile with the "unawareness of pain" view. For example, some animals demonstrate pain-related behaviours well after the initial nociceptive response would have faded. As pet owners know, animals can learn to avoid areas where they encounter pain (Rushen and Congdon 1986; Dunlop, Millsopp, and Laming 2006; Crook 2021). In other experiments, rats and even fruit flies learned to seek out stimuli experienced right after getting shocked, probably because these stimuli meant "the shock is now over" (Gerber et al. 2014). And as mentioned previously, some animals learn to self-medicate when in pain. In my estimate, these behaviors suggest pain awareness reaches higher-level cognitive processing and influences decision-making, rather than just triggering reflexive responses. (For more on animal sentience, again, see the essay by Benjamin Hilton.)

While the behavioural and neurological evidence isn't as robust as it is for pain, I think other important aspects of well-being, like pleasure, agency, social connection and feelings of awe, are probably also present in many animals. My favourite example is an experiment where octopuses spent more time, and engaged in more physical contact, with other octopuses after being given MDMA (ecstasy) (Edsinger and Dölen 2018). I only focus on pain because pain, or rather the absence of pain, seems extremely important to well-being -- probably more important than all those other aspects. When someone is in severe pain, almost nothing else matters except making the pain stop. The same is not true for most other negative experiences, or the absence of positive experiences.

How can we be sure that plants don't feel pain, too?

It is true that some plants respond to harmful stimuli and stress in some rudimentary sense. But plants almost certainly do not experience pain or suffering, as they lack nervous systems and brains. They are also far more distant from us evolutionarily than farmed animals: humans and cows/pigs diverged nearly 100M years ago, humans and chickens diverged around 300M years ago and humans and fish around 390M years ago, but humans and plants diverged around 1.5B years ago.

Do you eat fish? Fish don't feel pain.

I used to eat fish and, when I was a child, would occasionally go fishing with my uncles and cousins. I was not a successful fisher but I remember distinctly hooks being pulled out of piscine cheeks and our vigorously bludgeoning pike and perch to death with our boots. I also distinctly remember believing that fish don't feel pain.

It has now been over a decade since I last ate fish and I now think it's very likely that fish do in fact feel pain, though the case is weaker than for birds and mammals (Brown 2015; Lambert et al. 2022). Even if fish are less sentient than mammals, eating fish might cause more total suffering because you need to kill many more individual fish to get the same amount of meat. For example, replacing one cow with thousands of sardines or dozens of salmon could mean causing more total harm, even if each individual fish has less capacity for suffering. Comparing moral status across species is incredibly complex and difficult but also unavoidable if we want to make moral decisions. We are constantly making choices that (explicitly or implicitly) compare the moral worth of different species.

How about bivalves like clams, mussels, oysters -- do you eat those?

I don't, but that is mostly because they are not very appealing to me. Since bivalves lack brains and have only rudimentary nervous systems, it is probably fine to eat them, and I know of several animal advocates who do.^[16]

Benefits to Humans from Eating Meat

Don't you find meat tasty?

I don't know. I certainly used to, though now I find the idea of eating meat off-putting. Either way, I grant that many people do derive substantial pleasure from eating meat and that this matters.

How much does it matter? I think preventing torture is clearly more important than having access to better-tasting food. We don't generally accept "but I enjoy it" as a justification for causing serious harm. Say you are willing to pay $X to upgrade a vegetarian meal to a pork-based meal. A modern pig yields enough meat for about 400 meals and lives for about six months until it's slaughtered, meaning each meal corresponds to about 14 hours of pig-life in a factory farm. (Or if you do not eat pork, take chicken. A meal of chicken would mean an entire week in a factory farm, because chickens are so small.) Now how much would you pay to avoid being confined to a factory farm for 14 hours? How much money would you need to be paid to let your dog, or a friend's dog, be treated like a factory-farmed animal for 14 hours?^[17] You'd probably pay more than $X to avoid the torture.

Don't you need to eat meat to feel healthy and energetic? Humans did evolve as omnivores. Meat provides calories and nutrients that benefit us.

It is true that we are omnivores who have essentially always had meat as part of our diets. It could have been the case that it was necessary for us to eat meat to be healthy. But the health effects of vegetarianism have been fairly extensively studied, and I think we can be confident that it is possible to eat a healthy vegetarian diet. There is no nutrient necessary for human health that can only be found in meat.

I previously reviewed evidence around the health effects of veganism, concluding that "vegan diets are healthier than common Western diets, and perhaps also somewhat healthier than good Western and non-Western omnivore diets [if] the vegan gets all the nutrients that they need". It is, of course, essential that vegans do get the nutrients they need, by supplementing some nutrients. But vegetarianism is far less restrictive than veganism, so supplementing often isn't necessary for vegetarians. For example, vitamin B12, which vegans must supplement, is available in dairy. That said, the health effects of vegetarianism and veganism is one of the areas in this FAQ that I am less sure about. I'm reasonably confident that vegetarianism especially is not significantly detrimental to people's health the way, say, drinking alcohol is. But it seems hard to rule out minor disadvantages (or advantages) given the current evidence base. It is probably a good idea to take a nutrition/vitamin deficiency test, regardless of your diet.

Can you get enough protein without meat?

Meat products do typically have more protein per calorie than plant-based products. But legumes like beans, lentils, peas and chickpeas are delicious, cheap and full of protein too. Nuts, seeds and whole grains (oat, barley, quinoa, brown rice, whole wheat) are also useful. Tofu and tempeh have about as much protein per calorie as eggs, salmon and beef. Depending on where one lives, there are also plant-based meats that improve in quality and variety every year. And, if you must, dairy products like milk and cheese are protein-rich. The Mediterranean diet is famously good and involves relatively little meat but lots of nuts, legumes and whole grains.

If you need a lot of protein, for example, because you are an athlete or go to the gym, there are plant-based protein bars and powder. I am neither an athlete nor a gym rat, but I am given to understand there are several successful vegan and vegetarian athletes and bodybuilders. For example, Carl Lewis, Lewis Hamilton and Venus Williams were all vegan during most of their careers.

But meat eating is a continuation of a long-standing cultural practice.

Here are some other long-standing cultural practices: chattel slavery, foot binding, public executions and female genital mutilation. A practice being traditional does not automatically mean we should continue it. It could mean we should be careful about stopping it, since it may have evolved to serve a useful function. Being careful about stopping eating meat means thinking through arguments like those presented in this FAQ.

We tend to think the way things happen to be, is the way things ought to be. For example, in discussions of efforts to cure aging and prevent death, people sometimes argue that doing so is wrong because aging and death is what grants life meaning. Those arguments are probably often the result of status quo bias. If the world were different and no one aged past thirty, and we could choose when to die, no sane person would ever advocate arbitrarily and compulsorily ending people's lives at a hundred, in order to make those lives more meaningful (Bostrom and Ord 2006). You can apply the same reversal test to meat eating by imagining a society where universal vegetarianism is the default and the moral burden of proof falls on meat eaters.

Aren't there animals that are raised with high standards, and that lead happy lives?

There surely are farm animals out there living happy lives. Those happy animals are almost certainly not living in factory farms, though, and, as mentioned, most animals raised for food are raised in factory farms. In the US, seven in ten cows, 49 in 50 pigs, and 3,332 in 3,333 chickens are raised in factory farms; the European numbers are likely similar. So I would need to actively seek out humane meat. If conditions in factory farms are as bad as I think they are, I would want to be very sure that the meat in fact did not come from a factory farm. Not only that, I would also want further evidence that the animal was treated well, since not all non-factory-farmed animals are raised humanely.

In practice, that seems like a tall order. If I buy meat in a supermarket, I can look for animal welfare labels, but food labels can be misleading -- for example, "natural" in the US only means no artificial ingredients, not that animals had outdoor access, as many think (Spain et al. 2018). Other labels are not regulated, or regulated but not verified. Knowing whether meat is humane is even more difficult if I am eating at a restaurant, in an airplane, while traveling abroad or at a friend's home. And researching different suppliers and standards costs time and effort.

Still, perhaps you could find some meat that you are highly confident is humane, and you could eat that meat while being vegetarian otherwise. Maybe wild game from hunting could count, for example.

Yes, perhaps I could. It is, of course, better to eat animals that were raised with high welfare standards than to eat those that were not, all else equal. There are three reasons why I still do not eat meat:

1. Even if an animal lives a happy life, someone still has to kill it for me to eat it. Everyone agrees that it's wrong to kill a human, even when he or she is not made to suffer.^[18] If animals also matter morally, it seems similarly wrong to kill an animal.^[19]
2. Strict vegetarianism (or in my case, veganism) offers useful signaling advantages. Vegetarianism is a clear, binary choice that others can easily verify and understand. That creates a clear coordination point for building social norms against factory farming. By contrast, humane meat eating is fuzzy -- it is hard to agree on what counts as humane and hard to verify that someone eats humane meat.
3. It seems better to me to have the clear boundary that vegetarianism (or veganism, or any other well-defined rule) provides. Once you start making exceptions, I think it often leads to a gradual slide back to regular eating habits, because there's no stable middle ground. Without a clear boundary, I think people tend to make more and more exceptions until their diet is mostly back to normal, and the original moral motivation becomes diluted. I think it is easier to stick to absolute rules, as they make lapses more obvious and harder to excuse, but even so, it is of course important to adopt pragmatic and achievable rules.

If I were to eat some amount of meat selectively, I would first of all make sure to eat beef rather than pork or chicken. That is because, to get the same amount of meat as I could get for one cow, I would need to eat three or four pigs, or nearly two hundred chickens. Also, pigs and chickens typically face harsher conditions than cows.

Benefits to Animals from Eating Meat

If everyone were to stop using animal products, cows, pigs and chickens would go extinct. Doesn't that seem bad for them?

I find it very unlikely that they would go completely extinct. Just like horses and carrier pigeons, animals that lose their practical use to humans don't go extinct, they survive as pets or in sanctuaries, just in smaller numbers.^[20]

All right, but there would be far fewer cows, pigs and chickens. Don't most cows, pigs and chickens owe their existence to us meat eaters?

I am not sure I know what it means for a life to be "worth living", but if the lives of factory-farmed cows, pigs and chickens were worth living, on the whole, despite being full of suffering, you could argue that eating their meat is good, as it creates more cows, pigs and chickens with lives worth living. Scruton (1996) makes this argument, though while criticising factory farming in particular. But I don't think the argument is sound. If a person who kept humans in captivity, who bred them for his or her own pleasure and who subjected them to a litany of abuses, justified his or her conduct by pointing out that the captives would not exist if it were not for him or her, and that the captives' lives are, despite the abuses, nonetheless worth living, you would take that for a very weak justification. That's a specific instance of what we could call the Human Substitution Test, which I think is relevant because it helps us focus on the fundamental ethical principles of how we should treat morally relevant beings.

Either way, given the conditions these animals endure, it is unclear to me whether their lives are, in fact, worth living. I would guess they are probably not. It seems likely that these animals have far more negative than positive experiences over the course of their lives. They have little ability to pursue goals or flourish in any way. They are also denied the kinds of social lives that are natural to them.

Don't farmed animals, in some sense, have better lives than wild animals? Farmed animals receive shelter, food, protection from predators and, at least sometimes, veterinary care. Wild animals face brutal natural threats like starvation, disease and predation.

The question is not, should we replace farmed animals with wild animals? It is, how many farmed animals should we have and how should we treat them? The protections we offer farmed animals don't justify torture. Psychiatric hospitals used to give their patients food, shelter and basic medical care while putting them in straitjackets, isolating them in padded cells, controlling every aspect of their lives, from daily routines to outside contact, and subjecting them to forced sterilisation, lobotomies, electroconvulsive therapy without anesthesia, medical experiments and more.

Why Think Meat Consumption Is Wrong?

When I buy meat in the supermarket, the animal is already dead. If I instead choose not to buy that piece of meat, it wouldn't magically cause the animal to revive. So how can you say eating meat is bad for that animal?

It is true that buying the meat is not bad for that animal exactly. But buying or not buying the meat affects future demand and therefore future animals. As a first approximation, if everyone stopped buying meat, there would be no meat industry, and if everyone started buying twice as much, the meat industry would grow to keep up with the growing demand. So it seems reasonable to think the meat industry would shrink as a result of reduced demand.^[21]

It also seems to me that, if it's wrong to directly harm someone, it's usually also wrong to pay others to do the harm. Huemer (2019): "For instance, murder is wrong; so it's also wrong to hire an assassin. If you hire an assassin to kill someone, you can't say that you're not to blame just because you didn't pull the trigger yourself."

Don't you think individual consumer choices have a negligible impact on large-scale meat demand and purchasing decisions made by supermarkets? Supermarkets purchase more meat than they sell, i.e., they have a buffer. If I stop buying meat, my local supermarket is extremely unlikely to reduce their order sizes.

If that were true, even a gradual mass movement of people stopping buying meat one by one would never affect production, which is absurd. An individual omitted purchase may often not have any effect. But each omitted purchase would have some chance of making the supermarket determine it is ordering too much meat. When it does, it will order substantially less meat. The same goes for each step of the supply chain. So on average, stopping to buy meat should reduce meat production.

Wouldn't reducing my meat consumption temporarily lower meat prices, leading other customers to purchase more meat?

When demand for meat drops, prices won't perfectly adjust to maintain production levels. Instead, because meat prices are relatively inelastic (resistant to change), some producers will be forced out of business rather than all producers simply lowering their prices (Gallet 2010, 2012). That would reduce supply and increase prices. While remaining producers might try to cut costs through efficiency measures that could harm animals, the overall effect would still likely reduce factory farming and animal suffering.

Richard Yetter-Chappell argues roughly that (1) eating meat is unjustified, but a relatively minor mistake in the scheme of things, (2) it's fine and extremely normal to make decisions that are less than perfectly justified and (3) other behavioural changes should be higher priorities, for example, helping animals by donating to effective animal welfare charities. What do you make of that argument?

I basically agree that becoming vegetarian is less impactful than donating to effective animal charities. Not because going vegetarian is ineffective, but because there are enormous opportunities to help animals through donations. There is a lot of uncertainty around these estimates, but it seems, for example, that for just one dollar donated to corporate campaigns for better chicken welfare, you can substantially improve 7-100 years of chicken life.^[22] Even if the real impact is at the low end of that range, that is still a very cost-effective way of reducing animal suffering. For comparison, the average American would save about 28 chickens per year by stopping eating them and, with broiler chicken living 47 days on average, that means 3.6 years of chicken life.^[23]

If you can only do one thing to help animals, in my view, donating to effective animal charities is more impactful than being vegetarian. But if you can do both, it seems better to do both. I recognise that for some people, going vegetarian would make it harder to donate, but I still think it's worth giving vegetarianism a proper try. Personally, I have not noticed the two trading off against each other.

Isn't it wrong to focus on individual consumption? Shouldn't we focus on getting laws passed and so on instead?

Why not both? I think for most people the best way to help get laws passed is to donate to effective charities working in policy and advocacy. So in a way this question is very similar to the issue of dietary change versus donating discussed above.

Disadvantages of Vegetarianism

Animals are harmed in plant production too. For example, field mice and other small animals are sometimes caught in crop harvesters, and then there are pesticides.

Yes, small animals are killed in plant agricultural production. There seems to be an enormous amount of uncertainty around how many are killed (Fischer and Lamey 2018). But I'm not sure it matters, because cows, pigs and chickens eat plants, too. While cattle -- especially beef cattle -- get a large portion of food grazing, where crop harvesters are not a problem but pesticides are still used, every calorie of beef produced requires 50 plant calories eaten. Factory-farmed pig (1 cal out = 11 cal in) and chicken (1 cal out = 8 cal in) feed comes exclusively from plant agriculture, mostly cereals and soybean (Alexander et al. 2016; Sporchia, Kebreab, and Caro 2021; Govoni et al. 2021). Alexander et al. (2016) estimates that the Indian diet needs 25% of the land the US diet needs to produce the same amount of calories, mainly because it's more vegetarian (getting 9% of energy from animal products, versus 30% for the US). The best (read: least worst) dietary impact estimate I could find has fruits, grains and vegetables killing 1-2 orders of magnitude fewer animals per calorie than meat:

As that graph shows, vegetarian diets are not free from harm. In particular, it seems really valuable to exclude eggs, probably more so than excluding beef. I am not making the claim that vegetarianism is the best thing ever one can do to help animals. For example, as mentioned, donating to effective charities seems to be more impactful than adopting vegetarianism. I am only saying that adopting vegetarianism seems much better than doing nothing.

How do you manage the higher (monetary) cost of a plant-based diet?

There are many vegetarian and vegan diets, some of which are as or more expensive than eating meat, others being cheaper. Legumes, grains and many vegetables are dirt cheap compared to meat. Some plant-based meats are more expensive than actual meat, probably because the meat industry benefits from economies of scale, decades of efficiency improvements and enormous state subsidies. (Western governments spend huge amounts of taxpayer money to support the meat industry -- about a third of the EU's entire budget and tens of billions in the US support meat production, in both cases far outstripping subsidies for fruit and vegetable production.) But other plant-based meats are affordable, and switching protein intake to legumes and whole grains is great economically. There is a reason why people in very poor countries eat very little meat.

Isn't being vegetarian really inconvenient? It seems to make it much harder to find good restaurants, to eat out when traveling (especially in rural areas) and it also means your friends and family will have to accommodate you.

It depends a lot on where you live. I live in urban Northern Europe where it is very easy and everyone is very understanding. In rural Iowa it would be harder. But I'd still try to be vegan or at least vegetarian even if it was really inconvenient. I would not eat humans just because it was convenient, so I also won't eat animals. The hardest bit is changing to the new diet, but sticking to it gets easier over time as you adapt and it becomes your new normal, assuming you don't develop significant health problems.

Don't all your arguments imply that everyone should be vegan too? That's even more inconvenient.

It is better to take smaller, achievable steps towards ethical goals than to do nothing because it is impossible to be perfect. I think most people should be vegan, or mostly vegan, if they are able. It seems especially valuable to avoid eggs and dairy from factory farms. But nobody's perfect and you do what you can. Making partial progress, like going vegetarian instead of fully vegan, or donating smaller amounts to effective animal charities instead of larger, is still valuable and worthwhile.

Implications

Do you want to ban eating meat?

No, I think a ban now would be wildly unpopular and unsustainable. I would like for norms to change to make eating meat less accepted, and vegetarianism and veganism more normal. I would also like to improve the welfare of factory-farmed animals. Maybe in the future, if and when public attitudes have shifted enough, a meat ban could become viable, but that is distant now. For now, there are many other good policies that governments could adopt, like banning battery cages and gestation crates and investing in alternative protein research.

Do you agree that vegetarians, and especially vegans, are preachy?

Yeah, occasionally. But that does not mean they are wrong. Don't do the wrong thing just because the people advocating for the right thing are annoying.

But also, I think the preachiness -- to the extent that it's there -- is fairly understandable and even defensible. If factory farming really is morally comparable to slavery in its severity, then people today who ignore or dismiss the issue are acting similarly to those in the American 1840s who casually accepted slavery as normal. How would you feel if everyone around you went on owning slaves, talking about slave-owning as something normal and fine and dismissing those pesky abolitionists for being judgy? You would probably be really, really tempted to suggest that perhaps they are in the wrong.

Do you think you're morally superior to those who eat meat?

Like many others, I used to eat meat without questioning it. Now, I recognize it as wrong, and those who consume meat are engaging in that wrong, while I don't. If we can compare people's morality, surely this counts in my favor in this particular area. Others are more virtuous than I am in other respects. So although I think eating meat is generally wrong, I don't think omnivores are generally evil. I've never met anyone without some moral failing.

That said, we should always strive to be better. When we eat meat we have, in my view, a great opportunity to reduce suffering in the world by changing our habits. If we realize we've been doing something wrong, the right response is neither to rationalize it as being acceptable nor to despair that change is impossible. Rather, we should acknowledge the issue and recognize that each small improvement makes a difference.

I'd like to stop eating meat but it seems pretty hard. I don't think I have the willpower.

The willpower needed to adopt vegetarianism varies tremendously from person to person. For me, though it took time, it was not that difficult, but I know that for some other people, it is. If you want to become vegetarian, you could start gradually by cutting out some products (like chicken and, ideally, eggs), or adopting the diet at home only, or only while eating out. You don't want to make the decision to eat vegetarian every time you sit down to eat. You want to make it once. So come up with a rule that works for you and stick to it. After a while, one improves at cooking plant-based dishes, discovers new vegetarian foods and (if one lives in the right place) finds good vegetarian-friendly restaurants and cafes, and it all becomes much easier.

But also, maybe ask yourself whether you really can't, or if you just think you can't. Lots of people have managed to go vegetarian -- do you think they're all superhumans with iron willpower? Huemer (2019) has a nice example: If you went vegetarian tomorrow, and had to pay $100 each time you ate meat, how often would you do it? If the answer is "never or at least very rarely", the urge to eat meat is probably not overpowering. Soon enough you will have internalized the "it's bad to eat meat" norm, and it will just seem normal and proper to you to not eat meat, and eating meat will seem strange and wrong.

I'd like to stop eating meat but I can't for some other reason.

Here is an incomplete list of things you can try instead:

• Offset your meat consumption by donating to effective animal charities. As I mentioned above, donating seems even more impactful than reducing one's animal product consumption.
• Cut out chicken, pork and/or eggs, in favour of beef or plant-based meats.
• Reduce your meat consumption, for example by designating one or more days in the week when you always eat vegetarian.

I'm still not convinced eating meat is wrong.

That is okay; I'm glad you stuck with me to the end.

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