Invertebrate Ethics

by Roger Crisp

In a recent and very interesting paper, Irina Mikhalevich and Russell Powell (MP) argue that the same standards of evidence and risk management that justify policy protections for vertebrates also support extending moral consideration to certain invertebrates. In this blog, I’ll offer two lines of argument broadly supportive of MP’s conclusions. First, even if invertebrates are non-sentient, their lives may contain elements of welfare sufficient for moral standing. Second, justice speaks in favour of giving priority to the interests of most invertebrates, since their lives are so much less valuable for them, in terms of welfare, than the lives of most vertebrates.

MP stipulate the capacity for experience as necessary for any ascription of welfare or well-being, and hence moral standing. They do recognize more expansive conceptions of moral standing, which, they say, might include items whose insentience is uncontroversial, such as bacteria, forests, and rivers. First, however, this issue is no longer uncontroversial in analytic philosophy. Panpsychism is now accepted by a non-trivial number of thinkers as a way to solve the ‘hard problem’ of consciousness. Second, and more importantly, there may be another argument here for attributing moral standing to invertebrates independently of their degree of sentience. Hedonist views of welfare of course include only sentient beings within their scope. But there is no obvious reason why desire accounts or ‘objective list’ accounts should do so. Imagine for example a ‘zombie’, without phenomenal consciousness, of the kind which MP mention. This zombie acts just like a being with such consciousness: if they go to the fridge and begin to drink, for example, it will be tempting to explain their behaviour through attributing to them a desire for a drink. We may wish to attribute to them some other form of consciousness, such as ‘access consciousness’, but that might also be attributed to invertebrates, independently of any capacity for phenomenal consciousness they may have. Now consider an objective list account of welfare, according to which, say, accomplishment, knowledge, and friendship are constituents of welfare, independently of any positive, hedonic conscious states to which they give rise. Again, such constituents of welfare might be found in the life of a zombie, and so therefore in the life of an invertebrate. Invertebrates, that is to say, are much more like zombies than they are like bacteria, forests, and rivers. Consider in particular the evidence cited by MP for high levels of invertebrate cognition. Even if, as far as subjective experience goes, there is nothing it is like for an invertebrate to cognize, cognition of this kind can plausibly be described as the acquisition of knowledge, and hence, on the objective list theory, a constituent of welfare.

Let me now turn to the matter of moral standing itself. When discussing whether allowing invertebrates under the moral umbrella would lead to a significantly demanding morality, MP rightly point out that, according to many views, this is not the case, since – to put it roughly – one’s moral significance may track the degree of sophistication of one’s mental life. We would not then, on this widely held view, have to give equal moral weight to, say, a honey bee and a young human child. If we have to save one or the other, perhaps, we are permitted, or even required, to save the child.

But there is a problem with this account of moral standing: it seems to discriminate in broadly the same way as racism or sexism, on the basis of morally irrelevant properties. Just because the child is more intelligent than the honey bee gives it no greater moral significance than their being white or male. What matters for each being, as MP imply, is how well the life of that being goes for it. And on most plausible views of welfare, the lives of most invertebrates will contain far less welfare than the lives of, say, dogs, or human beings. The possibility of having a life that is good or bad for one is, as MP suggest, very plausibly a necessary condition for moral standing. But purely on the grounds of justice, it seems, in any conflict we should give priority to the interests of the being whose life, overall, will be worse overall for it (on the assumptions that there are no issues of desert in play, and perhaps that the life of the worse off being is below some welfare threshold). Even quite a young child is likely to have had a life of much greater value for it than the life of a honey bee, so justice, in our example, seems to require choosing the bee.

On this non-discriminatory account of moral standing, moral demands may well increase radically. But perhaps this need not be the case if we allow in principles other than justice to determine our decisions. Consider, for example, impartial beneficence. Other things equal, saving the child is likely to produce much more overall welfare in the world than saving the bee. But here we do have to take into account, as do MP, the sheer number of invertebrates in the world. When these numbers are taken into account, morality may again become significantly more demanding, and significantly more strange in its demands, than we had expected. But, as in science, there seems no reason to assume in advance that morality will be easy, or common-sensical; indeed even common-sense morality can demand quite large sacrifices from us in certain situations for the sake of, say, preventing very great harms to many others.

There is also here a point to add to those made by MP in connection with moral uncertainty. Even if the probability is very small that the argument I have just made is correct, the numbers at stake are such that our current attitude to invertebrates may involve us in committing very great wrongs indeed.