 In a recent review essay on animal consciousness, Dr. Jonathan Burke, Associate Professor in the Department of Philosophy, Logic, and Scientific Method at the London School of Economics, asks the provocative question, can we know if non-human organisms possess the sense of, quote, there being something like it's, if there being something, it's like to be me, end quote. To be guiling nature of this question, it seems obvious, then not, then strange, there being something it's like to be me and to fly, then impossible, then maybe just a little bit plausible. Perhaps other organisms do have a sense of there being something it's like to be themselves. So reveals the fundamental moral question at stake. If consciousness, a sense of self, exists beyond us, then maybe we should, or maybe we must, think of ourselves as part of a broad network of conscious organisms and therefore extend our ethical obligations far beyond the human or the dog or the cat or the chimpanzee. Even, we could say all the way, of course, to insects. Through his work, Dr. Birch points us to one of the most fundamental questions in all of philosophy and ethics, not are we alone in the universe, but are we alone here on earth? In other words, are we the only beings who know that we are here? Emphatically, Dr. Birch thinks that we are not, and to listen to him make the case for why it is my great pleasure to ask us to warmly welcome Dr. Jonathan Birch to Nobel 59. Thank you, Sam, for that kind introduction. Thanks so much to all of you for being here. Thanks very much too to the online audience. In the airport on the way here, the immigration guard asked me, why are you visiting the US? And I said, for a conference. And he said, a conference about what? And I said, insects. And he said, I don't like insects. They're so small, we don't really know what they're up to. I wasn't able to persuade him otherwise in that interaction. Luckily he did let me into the country anyway, somewhat reluctantly. But I hope that over the course of the next two days, we have a bit more time, and we really can get you to see insects in a very different way. Help us all to get past the unjustified and excessive sense of revulsion that we sometimes feel when we interact with them. In this talk, I'm going to discuss my journey to taking insects more seriously, to recognizing that they have lives of their own, that they have minds of their own. In a way, I sympathize with the border guard because I do think it's very difficult. It's a difficult process, partly because insects are so small, as he pointed out, but partly also because they're separated from us by over 500 million years of evolutionary time. They've evolved along a completely different path to a very different way of life. Nonetheless, I've come to the view that just as they've evolved eyes by a very different route, eyes of their own, they've also evolved minds, minds of their own, by means of a very different route. Part of the talk will be about the science, because it's the science that has convinced me that insects have minds. But part of the talk will also be about ethics, because once we recognize that insects are beings with minds of their own, we need to start asking questions about what it is to take them seriously, what sort of ethical duties we might have towards them. I think part of the problem here is that we have to resist an outdated picture, a picture that asks, well, do insects really have minds at all? A picture that suggests they are just machine-like, that they are reflex machines. Think here about your own reflexes. Think about the knee-jerk reflex, or the gag reflex, or your reflex withdrawal of your hand when you touch a hot stove. There's no role for the mind in producing these behaviors. They are reflex behaviors triggered by the immediate sensory stimulus. And people have long said, well, maybe insects are like that. Maybe insects are just, maybe that's all they have. They're all just immediate reactions to the stimulus. But this isn't true. This has been replaced by a modern view, based on a huge amount of evidence, that insects represent things. They represent the world around them. They represent their own bodies. And they use these representations to guide flexible decisions. Much of the evidence for this is presented wonderfully in a recent book called The Mind of a Bee by Lars Chitka, someone who's been working on the topic of the minds of bees for many, many decades, and who it's been a real pleasure over recent years for me to develop a series of collaborations with, where we've been trying to bridge the gap between the science and the philosophy, including the ethics of insects. I mean, one question you might ask is, well, do insects represent the world around them? In fact, it's been known for a very long time that they have at least a simple kind of representation, because it's been observed for a very long time that the way they move around their environment is actually very intelligent. It's not random at all. If you think about bees in particular, and ants, insects that rely on foraging from their environment, they're very, very good at finding their way back to their nest after a foraging expedition. In fact, if they've had a very roundabout route across the landscape, they keep track of where they've been, and they go by the most direct route straight back to their nest in what's called path integration or dead reckoning. And how are they doing this? Well, they're using their brains. Their brains are keeping track of where they've been, what speed, for how far, and they're doing a computation to work out where do I need to go to get back to the nest. So it's been known for a very long time that at least that is going on in insects like bees and ants. But you might ask, well, do they learn, or is it that everything they do, including fancy things like path integration, is ultimately a kind of instinct that it's genetically programmed into them by evolution? Because undoubtedly a lot of what they do is genetically programmed into them by evolution, and that's part of the story about why it is so beautifully well adapted to their environment. But it's an outdated view to think that everything they do is a matter of instinct. The modern view says that, yes, there is a lot of instinct there. But instinct drives them to learn the things that matter to them about their environment. Lars Cicca some years ago thought, well, how could I prove this? Now, how could I show that it's not just instinct but rather learning? Well, one way to do it is to give bees tasks that they would never encounter normally in the wild. In an alborotree setting, you can control the task. You can give them tasks that they would never otherwise meet. Like, for example, you can give them a task where they fly into an arena and to access food in the form of sugar solution, they have to pull a string, and you can see whether they can learn to do that task. And they don't get it straight away. That really would be quite something if they got it literally straight away. It's not instinct, and there's no reason to think it would be instinct. But they learn. They learn by trial and error. And in fact, they get very, very good at it, as you can see from the bee in this video. They can end up going straight to the string, pulling it out, getting the reward. So, you know, only a few insects have been studied in relation to questions of learning. But honey bees are extremely good learners. Bumble bees too are extremely good learners even when the task is very unfamiliar. But you might ask, is that the only kind of learning they can do? Do they only learn by trial and error? Or can they also learn from each other? In fact, it's very clear that they do learn from each other in at least simple ways. The famous waggle dance is an example of this, that bees will signal through a kind of dance that is called the waggle dance where food is located in their environment. They'll also use that same mechanism to signal where good nest sites are, where they're scouting for new nest sites. So in a way, that's bees learning from each other because through feeling the waggle dances of their nest mates, they learn where the food is, they learn where the good nest sites are. But learning from each other is not limited to that. Even when the task is very unfamiliar, like that string pulling task I showed you, they can still learn from each other. They can learn by observing another bee doing the task, how to do it properly. From watching others do it, they learn what to do. They can even sometimes improve what they've seen. Here is another task that in Nars Chika's lab at Queen Mary, they set bumblebees. This time, the bee has to roll a ball into a hole to receive the reward. It's a kind of tool use, in effect. The ball is a tool. The bee has to learn how to use the tool to get reward. And it's really not obvious. So they don't get it straight away. They have to learn it. But then once one has learned it, others can observe the bee doing it, and they can learn to do it themselves. And moreover, they can improve on the first bee's performance. If they're shown a bee that always rolls the most distant of two balls into the hole, they don't just blindly copy what they've seen and go and roll the most distant ball in. They go straight for the nearer ball, and they roll the nearer ball into the hole, solving the task more quickly and efficiently. So they don't just learn from each other. They also improve on what they've seen. In my view, this makes a limited form of culture possible. They don't have culture in the same way that we do. You won't see a bee orchestra playing lovely musical interludes. But they have their own form of culture. They learn from each other. You can train one colony on one kind of technique for something like string pulling or ball rolling. You can train a different colony on a different technique, and they will pass those techniques down the generations. So when you come back, months later, to those colonies, you will still find them doing their particular tradition, their particular way of doing it. It seems very likely to me that that's exactly what's going on in the wild as well, that bees will form cultural traditions, different ways of doing things, different ways of navigating their environment. So you might ask, well, this has all been very kind of learning focused, very task focused, very focused on how bees solve the problems that they face in life. But is there more to the mind of a bee than that? For example, is there evidence that they enjoy life? Is there evidence that they have fun? Is there evidence that they can play? Well, there is now. This is thanks to one of Lars Tickers' PhD students, Samadhi Donna. She was asking, well, we've got these experiments where the bees roll a ball into a hole to get a reward. What if there's no reward? What if there's just some balls lying around in the environment, and the choice is either ignore them and get on with feeding or stop and play with them? And I don't know what you would have expected in that situation, but what Samadhi found was that they stop and play. Here's a video of a bee rolling a ball for no reward whatsoever. Of course, it depends exactly what we mean by play, whether this is play. But it's a behavior with no particular food reward. We don't know why the bee is doing it. But it's not implausible to think the bee is just enjoying rolling the ball for its own sake. That's the explanation you would jump to if you saw a mammal like a rat or a dog or a cat playing with that ball, and we should apply the same standards. We shouldn't have a double standard where evidence that we would accept for mammals. We don't accept when it's a bee. So if we think about what we've got so far, the learning, the representation, joy, play, it's very natural to then start to wonder, well, what about the negative side of mental life? What about pain and suffering? Of course, this is a more difficult topic to talk about. The experiments are inherently rather less fun, because you're trying to explore the question of whether there are aversive experiences associated with actual or potential tissue damage. And here, too, there's a view that I consider outdated. There's a view that insects just can't feel pain. And in support of this is people point to examples of cases where an insect has suffered a catastrophic injury and just carries on. That doesn't seem to react to it. Bees, for example, when they sting you and the sting is ripped out of them, they don't seem to display any obvious signs of pain in those situations. It's not clear why that is, but we have to be very wary about the mistake of thinking that the only way insects could feel anything like pain is in the sort of situations we would feel pain. That's not true. And there's a lesson, I think, from the case of sharks, where for years people would say, oh, sharks don't feel pain, because sometimes when a shark suffers a catastrophic injury, it just carries on. Like if it's clamped onto a seal or something like that, it will keep its teeth in the seal, even when it's lost its entire rear half. But if you think about it, as sharks have to keep swimming no matter what, there's no way in which they can stop a nurse and injury to the back half of their body. So there's really limited benefit to having a system that helps you nurse injuries that are completely unrecoverable anyway. What researchers have found, when they've looked at the case of sharks, is that there are pain receptors around the face and mouth region, which makes total sense when you think about it, because that's somewhere where a shark really can do something about it. That if a shark is being caused pain by something it's bitten into, it has the option of releasing and swimming away. So there's a lesson from this case that just because we don't see the animal displaying the sort of behaviors we would display, we can't conclude from that that it doesn't feel any pain. And in fact, another person associated with my project and in Lars's lab as well, Matilda Gibbons, now a postdoc at UPenn, has been asking, well, if we use more subtle stimuli, not catastrophic injuries, but more subtle things, like an experience of a heat probe on the antenna, do we see signs of pain and suffering in those cases? And we've come to the view that it's at least plausible, though not proven, that many insects can feel pain in some of these situations. We reviewed all of the existing evidence we could find in a recent review here. That's where we conclude that it's plausible. It's a possibility we should take seriously. And in her own experimental work, Tilda has been exploring the responses of bees to heat probes on their antennae and finding evidence that if you administer a heat stimulus to the antenna of a bee, it will selectively groom that stimulus, that antenna, which is what you can see in this video here, that the bee has had a heat probe to the antenna. Just as we might well nurse an injury we received in that situation, the bee here you can see grooming the affected antenna. So no one would call this conclusive evidence, but it is some evidence that might lead us to worry. Bees find strong heat unpleasant, and they will prioritize avoiding it over other needs, such as food, just as we would. This is the basis of another one of Tilda's experiments, that if you think about what pain does for us, what is it doing or not doing? Well, what it's not doing is controlling our reflex responses. So when you touch your hand to the hot stove and withdraw, that reflex withdrawal is already happening before you feel any pain. The pain comes later. The pain is doing something else. The pain is not triggering the reflex. What is it doing? Well, one thing it's doing is informing our future decision-making. You're probably not going to do that again because of the pain you felt the first time. And the way it informs our future decision-making depends on how intense the pain was. If you imagine yourself going for a run, you get a very slight little pain in your toe. You might slow down a little bit, but you're probably not going to stop running, and you're probably not going to avoid that course in the future. But if you think of a situation where you have a serious fall and break your leg and suffer really intense pain, that really will change your future decision-making, you're certainly going to stop. And you're probably not going to run on that particular route ever again. You're going to learn from your mistakes. And so Tilda wanted to explore whether bees make flexible decisions in this way as well. She created an experimental setup where the bees have to stand on heat pads to access sugar solution. Of course, it's in the nature of these experiments that they do involve unpleasant stimuli for the bees, which is in a way regrettable. But if you think about it, the importance of this research is absolutely huge. I think the potential benefits of learning that insects do feel pain are so significant that I can see totally why Tilda and Lars felt this research was important and justified. The heat pads are unpleasant for the bees to stand on. They're at different temperatures, and the sugar solution they can access is at different concentrations. So it's probing their decision-making. Are they willing to withstand a moderately hot surface in order to get a sweeter reward? Is there a threshold beyond which, if the heat pad just gets too hot, they won't go there even if the rewards are really, really sweet? And Tilda found that this is indeed the case, that they do make flexible trade-offs in this way, that if the rewards are sweeter, they will withstand hotter heat pads in order to access them. So we're far away at this point from the idea of bees as reflex machines. What they're doing is quite sophisticated decision-making. They're thinking, what are the opportunities this environment affords? What are the risks here? How bad are those risks? How much would it hurt? How good are those rewards? How sweet would the sugar solution be? And they're making a flexible decision on the basis of all that. A decision that in us would be very intimately related with feelings of pain and pleasure. So the science here is pointing to a very realistic possibility of at least some insects feeling pain. Some react to this by saying, well, why do insects have any need for pain? But once you accept all the stuff I said earlier about the sophistication of their mental lives, once you realize that they're learning, that they're making flexible decisions, that they're trying to weigh up risk and reward all the time, it's not hard to see why pain would really be useful for them because it helps them make those decisions much, much better just as it does in us. In fact, in humans, to be born without the capacity to feel pain is a terrible disability. Leads to absolutely disastrous consequences because you do not develop the ability as a child to think carefully about risk and reward and avoid injuring yourself. Pain may well be doing for insects exactly what it's doing for us. All of this science brings us to a discussion of ethics. How should we think of the ethical implications of the fact that bees have minds? Those minds might include feelings of pleasure and pain. Very important idea for me in thinking about these issues comes from British philosopher Jeremy Bentham writing in the 1780s. He says in a footnote, because the book he's writing is about humans, just as nearly all ethics at that time was about humans, in a footnote he thinks, well, how might the scope of our moral obligations actually expand beyond humans? And he says, well, the question is not can they reason or can they talk, but can they suffer? The test we should apply when asking whether to give moral consideration to other animals is not do they have language. It's not do they pass reasoning tests. We wouldn't apply those criteria to our fellow humans, to infants, for example. The question is can they suffer? Can they have feelings of pain and other aversive experiences? That idea was not really new to Bentham. He introduced it to the Western canon in philosophy, but in a way you can see it as the rediscovery in Western philosophy of an ancient Indian idea. It's the idea of a hymsa, non-injury, not causing harm to sentient beings. A duty that in Indian religions has always been understood as having very broad application to the whole of sentient life. In the eighth century, for example, a Buddhist philosopher Shanti Deva wrote very clearly, sufferings must be warded off simply because they are suffering. Why is any limitation put on this? I had the privilege earlier this year to visit India, went to Dharamshala and was able to speak to the Dalai Lama about some of these issues. And I asked him, do you think insects are conscious? And he said, yes, of course. There's never been any doubt about this in the Tibetan Buddhist tradition and in Indian traditions generally. It's rather the Western tradition that has introduced doubts on these questions. It's a big idea, I think, when you take in these comments from Bentham and Shanti Deva and you reflect on them and think about what they might mean for your life. Because what they're telling us is that ethics is not just about humans. Moreover, ethics is not just about humans plus our pets and plus those big charismatic animals that we love and that we interact with and empathize with. It's not just about humans, monkeys, chimpanzees, dolphins, cats, dogs. No, it's really about everything that can suffer. Any animal that can suffer deserves our moral consideration. All animals suffering deserves our consideration and compassion, even if, and this is the hard bit, I think, even if the animals in question are very small and look very different from us as insects do. Of course, in cases like insects, we're not sure. I think we should admit that too. I've presented some evidence, some evidence that I found very striking and that has persuaded me to take seriously the possibility that insects might feel something like pain. But it will be wrong to say we can be sure or that we've conclusively settled the issue. That definitely isn't right. And indeed, we've only been looking at a small number of insect species. Some of the most persuasive evidence, like the grooming of the antennae and the motivational trade-offs, concerns bees specifically. And even for bees, there's, of course, uncertainty. You can't be certain when you're thinking about a subjectively experienced state like pain. But I think crucially, we don't need certainty. We must not let the demand for certainty stop us from doing anything to help these animals. Even a realistic possibility of pain, based on some evidence, should make us stop and reflect and think what might we be able to do to relieve these animals suffering. There's another important idea here that, faced with uncertainty, as we always are when thinking about these questions, it's often wise to take precautions, to err on the side of caution, to give the animal the benefit of the doubt. So it's been a very important idea for me in my ethical and policy-facing writing on these issues. In 2017, I suggested a principle for policymakers on these questions that I called the animal sentience precautionary principle. It's based on precautionary principles in other areas of environmental policy. It's long been a very important idea in that area, in many countries around the world, that you should not wait for certainty when faced with a very serious environmental risk. Think, for example, of the case of CFCs and the ozone layer. Thank goodness we acted when we did, in the case of CFCs, because we could have destroyed the ozone layer and potentially annihilated all life on Earth without realizing even what we'd done. That's a cautionary tale that should lead us to think in a precautionary way about other environmental risks. And I've suggested we should think this way about questions of sentience, too. That where there are threats of serious negative animal welfare outcomes, continuing uncertainty as to the sentience of the animals in question, should not be used as a reason for postponing proportionate measures to prevent those outcomes. I proposed this in 2017 based on other precautionary principles. I think it's had some influence in the years since, but mostly in relation to invertebrates like octopuses and crabs and lobsters. I think we need to think about this in relation to insects as well. But of course, when it comes to insects, people start to worry, because when it's octopuses, it's easy to accept that we should protect their welfare because we don't rely on them in so many different areas. With insects, of course, we do rely on them totally for so many different things. And we kill a lot of insects in our daily lives, and we often regard them as pests. So it's important to ask the question, what are proportionate measures here? What are measures that would not be too disruptive to our way of life, but that would nonetheless help with the problem? We don't necessarily have to go as far as Jane ascetics do. They take the avow of a hymsa so very seriously that they sweep the floor in front of them with brushes so that they don't accidentally step on any insects. I think it's okay to not be willing to go that far and to not be sweeping the floor in front of you in your daily life, but that doesn't mean we, therefore, swing all the way to doing absolutely nothing. I think we need to look for proportionate measures, measures that do enough to control some of the main risks, but that don't go beyond what is reasonably necessary and that express a consistent attitude to different risks. So for example, I mean, I think we've already got very strong reasons to be protecting insects anyway, regardless of the question of whether they're suffering or not, for the sake of ecosystems, sustainability, maintaining a habitable planet. For example, think of the case of neonicotinoid pesticides. These are incredibly effective pesticides that, sadly, are rather too effective in that they've been credibly linked to decline of wild bee populations. In Europe, the European Union has acted on this and it's banned them on a precautionary basis. It's saying, we don't need certainty to act here. Think of CFCs. We don't need to wait around for certainty to take action to try and save these wild bee populations. And I think that's absolutely the right approach and it's now the target of campaigns across the US as well. I know there's legislation going through the Minnesota legislature, HF 1130, that proposes to give local cities the authority to regulate pesticides, if for example, to ban neonicotinoids. If that legislation goes through, the power to do something about this will be in your hands. The power to regulate some of these high-risk pesticides will be with you. But I think we should go at least that far. We should go at least that far to think about banning some of the most dangerous pesticides. But I think we should go further too. And in particular, I think we should try to get beyond this idea of only caring about insects for our own sakes. Only caring about them because we need to maintain a habitable environment for future generations of people. That's absolutely right. But in addition, we should also be thinking about protecting them for their sakes. We should care about their welfare because like us, they're sentient beings with lives of their own. This has implications when you think about insect farming, for example. Huge interest in insect farming is possibly part of the solution to sustainably providing for the world's protein needs. It's not a case where you're using pesticides and things like that because it is largely indoors. But I think for the sake of the insects, we should be trying to have high welfare standards in this kind of farming. We should say it shouldn't be a total free-for-all in which you can do whatever you want, slaughter these insects using any method you want. There should be regulation and it should be based on the latest evidence about what is actually a humane way to treat these animals. The problem we have is that the evidence is sorely lacking. No one's really been looking. This is the subject of my latest collaboration with Lars that we want to try and close some of these evidence gaps. We want to get evidence for crickets and for black soldier fly larvae about what the most humane ways of treating them actually are. What sort of things do they find aversive? What kind of conditions do they like? Let's do more research to try and find out what the insects need, want, like and dislike. And in fact, I've been involved in a project with a group of colleagues led by Megan Barrett to form a society to gather researchers from around the world who are interested in these questions. These questions have been so marginalised. They've been so neglected that the evidence base is incredibly thin. And yet in my view, for the reasons I was discussing, the importance is absolutely huge. So we founded Insect Welfare Research Society to try to promote more projects that are trying to find out what it is that insects actually like and want. So people have various worries about this. They sometimes say, well, that can't be the top priority right now, surely. Surely we have more important things to worry about than insect welfare. But I have two responses to this. One is that the problem is actually entangled with other huge problems and complicated waves. It's very tightly entangled with the project of finding ways to live sustainably, finding ways to create a habitable, natural environment, finding ways to stop the destruction that is threatening the very existence of our species. And my second response is that caring about animal welfare is not a zero-sum game. It's not that if you start caring for insects, you have to care a bit less about pigs, chickens, cats, dogs. Course not. No, you carry on caring about those. You carry on campaigning for better welfare for those. But you just expand the moral circle to include invertebrates as well as vertebrates. I think the time has come for that. I think the time has come to expand our moral circle to include insects. Thanks very much for listening. Thank you.