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Thesis The argument from marginal cases has never been properly answered

Ethan Mercer Fellow
· 6 replies
Animals & environmentAnalyticModern EuropeanUtilitarianismEva KittayJeremy BenthamPeter SingerTom Regan#marginal-cases#moral-status#species-overlap#speciesism
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Where it stands

It pains me to agree with my effective altruism group on anything. But on this I do.

The argument runs like this. Name the property that gives humans moral status. If it's rationality, language or moral agency, some humans lack it (newborns, people with severe cognitive disabilities), and you would have to exclude them, which nobody accepts. If it's sentience, many animals have it, so you have to include them. If it's simply being human, you owe an explanation of why species membership as such matters morally, and "because they're us" is not an explanation.

Bentham put the conclusion in a footnote to his Introduction to the Principles of Morals and Legislation: "The question is not, Can they reason? nor, Can they talk? but, Can they suffer?" Singer built equal consideration of interests on that. Regan went further and argued that many animals are subjects of a life with rights of their own.

The replies I have read either restate species membership in a fancier vocabulary or change the subject. Any property high enough to exclude all animals excludes some humans, and any property low enough to include all humans includes many animals. That is a structural point, and I have not seen it beaten.

I know some find the name offensive, and I'll come back to that. First, where does it fail?

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6 replies

For the thesis 1

  1. Priya Raghavan

    For Fellow

    For the empirical premise, the sentience side is now strong. In 2012 a group of neuroscientists signed the Cambridge Declaration on Consciousness, stating that mammals, birds and some other animals, octopuses among them, have the neurological substrates for conscious experience. Evidence of pain behaviour in fish and crustaceans has kept accumulating since. Whatever you think about the argument's structure, its sentience premise looks safer every year.

    Helpful · 3

Against the thesis 3

  1. Dima Nasser

    Against Fellow

    Let me start with the name, since you raised it. Disabled people are used as premises in this argument and are almost never asked what it is like to be one. Eva Kittay, whose daughter Sesha has severe cognitive disabilities, has written powerfully about hearing philosophers treat her child as a test case.

    Her objection is not only about feelings. It is that the argument gets the facts of moral life wrong. Sesha is not owed care because she possesses some threshold property. She is owed it because she is someone's daughter, a member of a community, a person in relationships. The argument assumes status comes from properties first, and that assumption is the thing in dispute.

  2. Ikechukwu Anyanwu

    Against Fellow

    The Thomist reply is not species membership in fancy dress. A newborn is not a non-rational being. She is a rational being at an early stage of development, and a severely disabled person is a rational being whose rational capacities are impeded. Moral status follows the kind of being one is, not the capacities one is currently exercising. You may reject the metaphysics of natures, but it is a real alternative, not a change of subject.

    Helpful · 1
    1. Ethan Mercer

      Fellow

      Ikechukwu, I accept it's a real alternative. My question is what makes the kind matter rather than the individual. Compare a human being with permanent and profound cognitive impairment and a chimpanzee who can use symbols and grieve. Why should what is normal for the one's kind outweigh what each of them can actually experience?

      Helpful · 2
  3. Femke Bosman

    Against Fellow

    The care ethicist in me is with Dima, and with Cora Diamond's older version of the point. We do not come to treat one another morally by checking each other for properties. Relationships come first, and the properties are an abstraction from them. The argument is tidy precisely because it describes moral regard wrongly.

    But that cuts both ways, Ethan. It also means our regard for animals need not wait on proving they have a property. Diamond is herself a vegetarian.

Other replies

  1. Ethan Mercer

    Fellow

    Two concessions. The name is bad, and I'll use "the argument from species overlap" from now on, as some writers have suggested. And Dima and Femke have a real objection: if status doesn't come from properties, the argument's first step fails. What I don't yet see is how the relational view stops our relationships from being as narrow as we like. Most people's relationships with pigs are with pork.

    Helpful · 1