Can octopuses feel pain and pleasure? What about crabs, shrimps, insects, or spiders? How do we tell whether a person unresponsive after severe brain injury might be suffering? When does a fetus in the womb start to have conscious experiences? Could there even be rudimentary feelings in miniature models of the human brain, grown from human stem cells? And what about AI? These are questions about the edge of sentience, and they are subject to enormous, disorienting uncertainty. The stakes are immense, and neglecting the risks can have terrible costs. We need to err on the side of caution, yet it’s often far from clear what ‘erring on the side of caution’ should mean in practice. When are we going too far? When are we not doing enough? The Edge of Sentience presents a comprehensive precautionary framework designed to help us reach ethically sound, evidence-based decisions despite our uncertainty.
... from "Five Books":
"Jonathan Birch is a philosopher with a research team at the London School of Economics. He’s particularly interested in the idea that we ought to base our ethical interactions with animals on scientific studies of what animals are actually like. So he works with zoologists, ethologists, people who look very closely at animal behaviour.
"There are amazing studies that reveal for instance, that individual honey bees are able to learn and are even capable of playing. An insect, which doesn’t seem highly intelligent, and which normally functions as part of a hive, can exhibit surprising abilities if you look closely at what it’s actually doing, or put it in laboratory situations that allow those capabilities to emerge.
"Jonathan’s interested in a very wide range of species, and often in species that don’t have cute faces. We don’t tend to attribute the same sensitivity and capacity to feel pain to an insect that we might to a sweet puppy or a baby chimp. Take lobsters. They are killed in quite gruesome ways for culinary purposes. He’s been involved in research that suggests that lobsters have quite sophisticated neural networks and seem to exhibit pain-like behaviour in certain situations. There is sufficient evidence, he believes, to exercise what he calls ‘the precautionary principle.’"
That we should assume they feel pain, just in case?
"Yes. The precautionary principle is this: once you get over a threshold of evidence, treat animals as if they are sentient even though there is still some doubt. He’s not saying they are sentient, but that there is sufficient evidence to be more careful about how we treat them. So, you don’t want to drop them in boiling water and let them die slowly, for example. If we are set on killing them and it’s possible to stun lobsters or kill them electronically, then we should do this rather than resort to the boiling water in a saucepan method of killing them.
"As I say, he’s not conclusively arguing that they do feel pain. This is the driving force in the way he approaches moral issues around how we treat other animals. If it seems they have the capacity, and there’s scientific evidence to back that up,, then let’s be more careful than we have been to date. Obviously, a lot of factory farming would be beyond the pale for him."
Quite rightly, I think.
"Agreed. But many people find it difficult to imagine that, say, fish or insects have sophisticated capacity for pain, even though the evidence supports the idea that they probably do.
"Birch is a superbly clear writer, and he’s very careful to adjust his belief according to the evidence. He’s not a sentimental animal ethicist who thinks, gosh, killing a mosquito is the same as killing a fox. He bases everything that he writes on the available science and sound reasoning from the best data we have.
"He’s one of the most interesting public philosophers around today because of his willingness to engage with ideas which have a very broad interest across the world. He’s also adept at dissemination those ideas. By making his book freely available online he has guaranteed a wide readership. He appears on podcasts, radio, and television and is frequently interviewed, more often these days on the potential sentience of AI than on animals. But his deep interest is in sentience in animals."
(by Jonathan Birch, ISBN 9780192870421)
Last modified 28 April 2025