Three years ago, a televised taste test of a lab-grown burger proved it was possible to grow a tiny amount of edible meat in a lab. This flesh was never linked to any central nervous system, and so there was none of the pain, boredom and fear that usually plague animals unlucky enough to be born onto our farms. That particular burger coalesced in a substrate of foetal calf serum, but the goal is to develop an equally effective plant-based solution so that a relatively small amount of animal cells can serve as the initial foundation for glistening mounds of brainless flesh in vats – meat without the slaughter.

For many cultured-meat advocates, a major motive is the reduction of animal suffering. Vat meat avoids both the good and the bad of the mixed blessing that is sentient existence. Since the lives of animals who become our food are mostly a curse, producing mindless, unfeeling flesh to replace factory farming is an ethical (as well as literal) no-brainer.

A trickier question is whether the production of non-sentient flesh should replace what I will call ‘low-suffering animal farming’ – giving animals good lives while still raising them for food. Ideally, farmed animals would be spared the routine practices that cause severe pain: dehorning, castration, artificial insemination, branding, the separation of mothers from calves for early weaning, and long, cramped truck rides to slaughterhouses. But even in its Platonic form, low-suffering animal farming has detractors. If we give farm animals good lives, it presumably means that they like their lives and want to keep living – so how do we justify killing them just to enjoy the tastes and textures of meat? By avoiding all the good aspects of subjective experience, growing faceless flesh in vats also escapes this objection. Since vat meat cannot have any experiences at all, we don’t take a good life away by eating it.

This could avoid what many see as the fatal contradiction of humane animal farming: it commits us to treating animals with love and kindness… before slashing their throats so that we can devour their insides. It’s not the most compassionate end to a mutually respectful cross-species friendship. However, conscientiously objecting to low-suffering animal husbandry can be paradoxical as well. Those who want plants and nerveless animal cells to replace all animal farming because they think it wrong to kill happy creatures seem to believe that life for these farmed animals is such a good thing that it’s a shame for them to lose it – and so we should never create their lives at all. They love sentience so much, they want this to be a less sentient world.

So, which of these awkward positions has more going for it? In order to figure this out, I’m afraid we’ll need a thought experiment involving, well, zombie cows.

In philosophy discourse, zombies are creatures who look and act like sentient beings but have no conscious experience. Typically, these philosophy zombies come in human form, but we can also conceive of deceptively lifelike clockwork cows that have nothing going on inside. For René Descartes, this would have been an accurate description of all cows, since he believed that humans were the only truly conscious animals. However, the view that animals are biological automatons is rare today, so Descartes’ perhaps apocryphal experiments on live dogs are horrifying to us, and the thought of zombie animals is perhaps a little creepy. To make this thought experiment a little less weird, then, let’s pretend there is a small section of normal brains that is solely responsible for the arising of consciousness and has no other function, and that the zombie cows are missing only this one part due to a developmental fluke.

Now imagine half of all farm cows are conscious and feel pleasure and pain. The other half are zombie cows in a dreamless sleepwalk that makes them indiscernible from the regular cows. The farmers in this thought experiment are committed to the strictest ideals of low-suffering animal farming and have no idea that half their cows are unfeeling bio-robots. Those who want non-sentient material such as plants and vat meat to displace all animal farming should see no major ethical problem with raising and killing the zombie cows. There might be environmental issues, or worries about farmers becoming desensitised to violence, but there can be no concern about the zombie cows for their own sakes. When a farmer fires a shotgun into a zombie cow’s brain, this does not deprive anyone of future pleasant experiences since the zombie cow never experienced anything in the first place. Opponents of farming sentient animals should therefore want all cows to be zombie cows.

when exactly is zombie-cow farming better than happy-cow farming if the main problem is death?

Firing a shotgun into the brain of the sentient cow is more ethically troubling – even if the death is painless – because that cow potentially had years of simple pleasures ahead of it, and death means it can never munch on grass, sniff flowers or nuzzle friends again. But, say the advocates of low-suffering animal farming, if raising either zombie cows or sentient cows offers us humans roughly the same benefits, and if we think the world is better for having more positive experiences in it, we should want all the cows raised in these circumstances to be sentient cows, not zombies. So, which should we prefer: zombie cows that never experience anything or sentient cows that live the good life before they lose it all?

A challenge for those who favour zombie cows (or non-sentient vat flesh) is for them to point out when exactly zombie-cow farming is better than happy-cow farming if the main problem is death. Let’s say it’s execution day at Happy Farm, and two cows have been scheduled to die – one of them sentient and the other a zombie. The sentient cow has had a pleasant life. The zombie cow has had no experiences whatsoever. The two cows are shot in their heads simultaneously. The sentient cow dies instantly, and now both cow bodies are non-sentient. It seems that at the moment the shotguns are fired, the normal cow is deprived of future goods, and the zombie cow is deprived of nothing since it had nothing. This clearly makes execution worse for the sentient cow. On the other hand, the mental features of the sentient cow and the zombie cow have now become identical.

Whether or not you believe that humans have souls, few people are substance dualists when it comes to cows, which means that we should approach this case as if death entails non-existence. From this physicalist perspective, we can’t draw serious distinctions between various possible conceptions of non-existence, and so we cannot say there is something distinct about death for the sentient cow compared with the persisting non-existence for the zombie cow. To say post-life non-existence is worse or different in some way than never coming into existence does not make sense if death just is non-existence. ‘It’s good that farm animals are not born because this spares them from death’ is like saying: ‘It’s good that farm animals are non-existent because this spares them from non-existence.’ The fact that the normal cow was killed as opposed to dying some other way doesn’t change the nature of its sudden-onset non-existence either. The formerly sentient cow who has died is not worse off than the zombie cow that was always non-sentient. They are, to put it awkwardly, the ‘same off’.

To recap, the sentient cow has had a good life, and the zombie cow has had no life. For those who think that a life consisting largely of happy states is more valuable than no conscious life at all, this scores a point for the sentient cow. At the moment of death, when it should be revealed how zombie-cow farming was really the most ethical option all along, the formerly sentient cow and the zombie cow storylines perfectly converge, with no material difference to be found. Both are non-existent. So where’s the winning point for the zombie cow?

Well, maybe there is a difference between the dead zombie cow and the dead formerly sentient cow, but it’s just not a physical one exactly. Zombie advocates could say that the formerly sentient cow loses potential future experiences at death, and so is harmed by this deprivation, while the never-sentient cow avoids that harm by not having life to lose. Cicero considered an extreme version of this take in a stoic consolation dialogue that James Warren interprets in ‘The Harm of Death in Cicero’s First Tusculan Disputation’ (2013). The dialogue features a character named A who believes that every mortal is miser (wretched, or severely harmed) while they are alive because they eventually have to die, and that once they die, they continue being wretched forever, since they once had life and then lost it. Warren writes that such a view would ‘appear to have consequences for concerns about future generations because it asserts that being a living mortal is harmful precisely because of the inevitable death to follow. In that case, it would appear to be wrong to cause anyone to come to be, as this is to cause them harm.’

Cicero’s probable stand-in, M, quickly disabuses A of this extreme pessimism about life and death by pointing out the fatal contradiction in his view: A thinks the dead are wretched because they no longer are. But as M forces him to grudgingly admit, to be wretched, you have to be! In his essay ‘Death’ (1979) Thomas Nagel gestures toward A’s original belief by suggesting that a natural limit to human lifespan does not in itself prevent death from being a deprivation, whether at age 150 or even 8,000. John Broome offers a more moderate stance in ‘The Badness of Death and the Goodness of Life’ (2012), writing: ‘What you lose by dying is the finite difference between a longer life and a shorter one. … The badness for you of your death is the difference between the goodness of the longer life you would have led had you continued living and the goodness of the life you actually do lead.’

This means that a cow who is painlessly killed on her 20th birthday has only a mildly regrettable death if a few days of good life was all she had left anyway, while a cow who could have lived to 20 but dies aged two misses out on 18 good years. And, again, a zombie cow loses nothing at death, because it has no future in store either way.

Breeding non-sentient cows is no better than giving them short but good lives if the problem is that they have less good life

This has implications for us, too. We will all almost certainly die at least somewhat earlier than we counterfactually might have, and therefore will lose something through our deaths. Does the risk of this loss make life too perilous to start? Should we not only wish for cows to be zombies, but for humans to be non-sentient so we can avoid the sting of death as well?

In Creation and Abortion (1992), Frances Kamm presents an argument for ‘No’:

[T]he principal misfortune of death is not receiving any more of the goods of life, but not receiving more goods is not worse than not receiving any in the first place. One is not harmed by receiving something rather than nothing. … Death is bad for a person primarily because it deprives him of more life. If this is true, then why should it be better for him, from the point of view of his best interests, to have had no life at all than to have had a short life? It is true that we are susceptible to the harm of being deprived of more life only because we do have some life. Yet, the suggestion is, avoiding this harm of deprivation does not seem to be a reason to avoid creating some life. That is, in this case one is not harmed overall by coming to exist and then having the harm of being deprived of life happen. … In short, death, including its deprivation of more life, may be the sort of bad thing that it makes no sense to avoid for the sake of the person (the foetus) created, by not creating it at all.

Kamm had abortion in mind, but the argument could be applied to our hypothetical cows. If death is regrettable because it deprives us of a future, the death of a cow at age two is a misfortune because she would have benefitted from having had more good life. However, having a good life that quickly ends does not leave the cow worse off than having no life whatsoever – it leaves the cow the ‘same off’ as having no life whatsoever, since non-existence is generic. Breeding non-sentient cows or growing flesh in vats is not any better than giving cows short but good lives if the problem with death is that it reduces the amount of good life being enjoyed.

But maybe the opposite is true. Perhaps low-suffering animal farming actually leads to a less sentient world. In ‘Least Harm: a Defence of Vegetarianism from Steven Davis’s Omnivorous Proposal’ (2003), Jason Gaverick Matheny makes this claim. He writes that, because animal farming is an inefficient use of land compared with vegan agriculture, we could boost the overall sentience in the world if we farmed only plants and used the leftover land to make room for more human or wild animal lives. The question then is how the lives of wild animals stack up against those of happy farm animals. In his paper, Matheny assumes wild animals have it pretty good, but a growing number of animal advocates think that wild animal lives tend to be rife with disease, fear and pain.

This is a point that Ben Levinstein and Anders Sandberg make in ‘The Moral Limitations of In-vitro Meat’ (2015). For those who care more about quality of life than quantity, low-suffering animal farming might be better than a vegan world with more wildlife. However, the difficulty of life in the wild might not be inevitable. By distributing vaccines to wild animals to reduce their suffering from disease and offering them emergency food, protection from predators and natural disaster assistance, we could take the edge off. Wild animal lives might even become better than those of pampered, dependent farm animals.

This does not, however, make the case for lab meat. If we’re really out to maximise wildlife, we should probably adopt an ultra-efficient vegan diet of beans, whole grains, seaweed and B12 pills. Regardless, it’s unlikely that we’ll do the very best thing for animals when it comes at a high cost for ourselves, which makes it worthwhile to compare imperfect but realistic possibilities such as lab meat and small-scale animal farming. If low-suffering animal farming and non-sentient flesh factories turn out to be equally efficient when it comes to land use, fans of sentience could still favour animal farming over vat meat, no matter how good or bad wild animal lives are. But vat-meat optimists argue that mass-producing cultured meat will be much more efficient than low-suffering animal farming, and so it’s still far from clear that the rejection of all animal farming will lead to a less happy, less sentient world.

There is something else to say in favour of farming only non-sentient stuff, and it has more to do with us than with the animals we farm. Maybe we don’t want to see ourselves as smiling villains taking care of animals who are oblivious to our true intentions, which is to kill and eat them. Two and a half years ago, I spoke with Bob Comis, a pig farmer in New York State who was writing a blog that occasionally veers into dark territory. In one post he wrote:

This morning, as I look out the window at a pasture quickly growing full of frolicking lambs, I am feeling very much that it might be wrong to eat meat, and that I might indeed be a very bad person for killing animals for a living.

Sick of the remorse he felt for sending thousands of trusting animals to their deaths, Comis finally sought redemption through vegetable farming and veganism. Animal-farming advocates could say that fewer pigs die because of Comis’s career switch, but only because fewer pigs live in the first place. Comis has replaced the ebb and flow of sentience to non-sentience in pig farming with the consistent non-sentience of plants. How much of an improvement is this, really, if we think pleasant sentient life is a good thing? But for Comis, who hated to think of himself as a killer who abused his pigs’ trust, it is a vast improvement.

Comis’s conflict epitomises this whole bizarre ethical conundrum over killing and sentience. Killing sentient beings is bad because sentience is good. But this judgment against killing can end up making sentience bad, since morally objectionable killing is possible only when there is sentient life at stake. To avoid being killers, we want there to be less sentience, because we think sentience is good!

Kill-free meat might sound nice, but it’s kill-free only because it never had any life to end

For me, the strongest point against low-suffering animal farming is the worry that, given humans’ track record, we cannot be trusted to handle commercially farmed animals with care. The veganism advocate Gary Francione denies that happy animal farming can live up to its ambitions because speciesism and human supremacy is baked into all animal farming, even its high-welfare forms. If we think that humans are better than other animals, and if we have all this power over their lives, won’t we be tempted to cut corners in our treatment of them whenever that benefits us? In other words, while it is physically possible to raise animals for food in conditions that give them good lives, it is not psychologically feasible for humans, at least not reliably. So the idealised animal farming I’ve described is mostly fantasy.

I think there’s something to this – enough so that it helped convince me to go mostly vegan earlier this year – but the difficulty of living up to low-suffering ideals in animal farming is a practical consideration, and one we might overcome with the right philosophical beliefs, culture and public policy. In theory, those of us who generally value a happy sentient world over a lifeless void should be suspicious of anyone peddling a less sentient world as a solution to the tragedy of life’s end.

At some point, humanity might be deciding whether to farm any animals whatsoever, and the path we choose could hinge on whether we want to create good but brief lives as a side effect of our desire to eat fleshy foods. Kill-free meat might sound nice, but it’s kill-free only because it never had any life to end. There is a danger to sentience, since it can go very wrong for those who have it. But this calls for caution and care, not for swearing off the creation of vulnerable sentient life altogether.