Why is sentience ethically significant?
Animals: Tradition - Philosophy


Robert C. Jones, Ph.D.
March 2018

Sentience confers on its possessor an interest in avoiding pain, an interest that commands ethical attention. The more we discover about which species are sentient and to what degree, the greater our obligations to end animal suffering everywhere.

Despite disagreement on precisely how to end the suffering of nonhuman animals, one thing that we can all agree on is that beings who possess the capacity to experience pain have an interest in avoiding pain and suffering. But why is that? Subjective experience is the key here — and sentience is the ticket into the moral community.

Is all life more important than all non-life?

Consider the differences between a rock and a cat. There are many, but on first blush, the main difference might seem to be that the kitty is alive while the rock is not. Though true, is this the central reason that we grant a higher moral status to the cat than to the rock? Is it because the cat is an animate object and the rock an inanimate object that the cat demands our moral attention in a way that the rock does not? In other words — all things being equal — does life trump non-life? The answer may seem an obvious, "Yes!" But let's do a little thought experiment. Imagine you were forced to choose between destroying the Rosetta Stone or killing one single bacterium. Whichever you would choose to destroy, it's certainly not obvious that you should destroy the Rosetta Stone merely because it's a "rock". And if that seems right, then it's not clear that the moral value of all life trumps all non-life. However, imagine it turns out that bacteria can feel pain. That might complicate things, and that's because sentience is, as it should be, morally significant.

As Peter Singer writes, "[i]f a being suffers, there can be no moral justification for disregarding that suffering, or for refusing to count it equally with the like suffering of any other being. But the converse of this is also true. If a being is not capable of suffering, or of enjoyment, there is nothing to take into account".

Subjective experience grounds basic moral considerability

In thinking about the cat/rock distinction, the salient ethical difference is not the fact that the cat is alive and the rock is not, but rather that the cat is sentient and the rock is not. Why is the fact that the cat feels pain ethically significant? To answer that, we need to take a step back and look at the notion of subjective experience. This is what philosophers like to call the what-it's-like aspect of existence. The fact that kitty even has a perspective — a perspective that includes the ability to feel pain — is what's important here. From the cat's perspective, she has interests that matter to her from the inside, for example, interests in her own well-being. Basic notions central to morality itself — concepts like justice, fairness, reciprocity, obligation, etc. —depend upon the possession of interests. The cat's ability to feel pain generates an interest (in not feeling pain), which ground her moral significance.

But isn't the choice of sentience privileged, anthropocentric, and arbitrary?

Sometimes, when I argue for the obvious and noncontroversial claim that possession of the capacity for pain and suffering makes the possessor morally considerable, I am confronted by the following challenge:

Why pick out pain as the criterion for moral considerability? There are so many other abilities and capacities that one could see as being morally relevant. Your view might not be speciesist, but it's certainly sentientist, privileging the capacity for pain and suffering over other capacities that might be more morally relevant (such as the capacity for empathy or reciprocal behavior) and ignoring other domains of moral significance such as non-sentient life (e.g., trees) or entire ecosystems. Focusing on sentience seems arbitrary and ungrounded.

Sentience is not arbitrary

First, the claim about the moral significance of sentience does not say that sentience is the only morally relevant capacity. It merely says that the capacity to experience pain and suffering is sufficient for entrance into the sphere of things that are morally considerable: if you’re sentient, you get a ticket into the moral community. Once you’re in, then we can weight values by considering various other capacities, properties, and relations to help us determine moral significance and adjudicate moral disputes.

Second, I must ask those of you who see the choice of pain as arbitrary to reflect on how you would feel about someone who caught stray cats and set them afire merely because he thought it was fun. Now, reflect on why you feel that way. If you think that the fact that the cat can suffer isn't sufficient to give you any moral reason to refrain from burning her, then I despair at what to say in reply.

Clearly, sentience confers on its possessor an interest in avoiding pain, an interest that commands ethical attention. The more we discover about which species are sentient and to what degree, the greater our obligations to end animal suffering everywhere.

Further reading

  • Gruen, L. (2011). Ethics and animals: An introduction. Cambridge University Press.
  • Jones, R.C., (2013). Science, sentience, and animal welfare. Biology and Philosophy, 28(1), 1–30.
  • Nagel, T. (1974). What is it like to be a bat? The Philosophical Review, 83(4), 435–450.
  • Proctor, H.S., (2012). Animal Sentience: Where Are We and Where Are We Heading? Animals 2, 628–639.
  • Singer, P., (2002). Animal Liberation, 3rd edition.

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