A Defence of the Species Membership Approach

Res Publica https://doi.org/10.1007/s11158-025-09759-2 A Defence of the Species Membership Approach Raffael Fasel1 Received: 27 July 2025 / Accepted: 2 December 2025 © The Author(s) 2025 Abstract This article responds to challenges raised by John Olusegun Adenitire, Alasdair Cochrane, and Maneesha Deckha in this special issue on my book More Equal Than Others: Humans and the Rights of Other Animals, specifically targeting my theory of the Species Membership Approach (SMA). According to the SMA, legal rights and other legal entitlements should be granted to non-human animals on the basis of their species membership, not their individual capacities. The article first takes on a principal competitor to the SMA: Adenitire's and Cochrane’s sentience-based theories. I argue that these theories are unlikely to satisfy many human rights proponents because: they exclude some human beings from rights protection, they do not do enough to show that sentience is a binary capacity that can provide a solid foundation for basic equality, and they justify rights by, and proportion them to, the properties of individual beings. As a result, they are unlikely to satisfy many human rights proponents. Second, I address Deckha’s challenge that the SMA manifests a problematic human-first mindset which reinforces existing species privileges. I respond by demonstrating that the SMA does not, in fact, adopt a human-first mindset, and that even my book’s more specific discussion of how human rights could be temporarily prioritised does not make my theory problematically anthropocentric. Keywords Species membership approach · Animal rights · Basic equality · Sentience · Anthropocentrism Introduction In The World as Will and Representation, Arthur Schopenhauer offered practical advice to readers put off by the book’s preface: reading, he noted, is just one of many things one can do with a book. One can also fill a gap in one’s library with it, gift it to a friend, or one can—‘by far the best option of all and one that I would particularly Raffael Fasel 1 Faculty of Law and Jesus College, University of Cambridge, Cambridge, UK R. Fasel advise’—review it (Schopenhauer 2010, p. 10). I hope that the respondents to this symposium were not put off by my book. But even if they were, I am grateful that they still followed Schopenhauer’s recommended course of action and reviewed it. Indeed, I could hardly have wished for a more distinguished group of scholars to scrutinise my work, and I am delighted to present my response to their insightful pieces in the following pages. To do justice to the breadth and depth of the issues which they have raised, I would need to go well beyond the confines of this article. I will therefore limit myself here to zeroing in on some key issues that are raised across the different responses and whose treatment might help advance debates beyond my own book. I begin by clarifying the parameters of my engagement with Alasdair Cochrane’s theory of sentient equality, which holds that all sentient beings have equal moral worth, as well as John Adenitire’s like-minded account. I give further reasons for doubting that their sentience-based theories can satisfy many human rights proponents, among other things on the contested issue of whether sentience is a binary property that can provide a solid foundation for basic equality (Sect. “Do SentienceBased Theories Meet Salaville’s Challenge?”). I then take on Maneesha Deckha’s challenge that my theory reflects a problematic human-first mindset that reinforces existing species privileges. As I show, my general theory does not adopt a human-first mindset, and even my more specific discussion of how human rights could temporarily be prioritised does not make my theory anthropocentric in problematic ways (Sect. “Sect. “Humans First? How (not) to Operationalise the SMA”). Do Sentience-Based Theories Meet Salaville’s Challenge? As my respondents note, my book seeks to offer the Species Membership Approach (SMA) as a way to overcome challenges that some of the dominant conceptions of human rights and animal rights have faced. According to the SMA, fundamental legal rights and other legal entitlements should be granted to animals on the basis of the species to which they belong, and not based on the animals’ individual capacities or interests. The SMA is intended as a middle ground position that offers a practical, rather than theoretical, solution to the problems encountered by the two opposing fundamental rights conceptions portrayed in the book. The Meritocratic conception (Meritocracy for short) extends rights to individuals purely based on their individual capacities and interests. This individualistic approach requires giving more and stronger rights to beings who possess more capacities and more well-developed interests. The problem with this conception is that it threatens to undermine the basic equality of human beings, jeopardising the rights of vulnerable human beings in particular (Fasel 2024, Chap. 4). By contrast, the Aristocratic conception (Aristocracy) reserves fundamental legal rights to members of the human species so as to protect the rights of all humans. The weakness of this conception is that it is at odds with the fact that many non-human animals have been shown to possess similar interests to humans, yet receive none of their rights (Fasel 2024, Chap. 3). The SMA solves the Meritocracy’s problem by making rights dependent on species membership, not individual 13 A Defence of the Species Membership Approach capacities, thus upholding basic equality; and it addresses the Aristocracy’s problem by extending rights beyond the human species (Fasel 2024, Chap. 7).1 One of the peer reviewers of my book suggested that sentience-based rights theories (which ground both humans’ and animals’ rights in sentience) uphold the equality of humans while allowing for an extension of rights to deserving non-humans. This, the argument went, would appear to obviate the need for the SMA. This is because, if sentience-based theories allow the extension of rights to animals without undermining basic equality and thus without threatening the rights of vulnerable humans, then these theories would seem just as, and potentially even more powerful, than the SMA. To test this argument, I devoted Chapter 5 to analysing Cochrane’s leading theory of sentient equality. I mention this to clarify that the scope of my engagement with Cochrane’s theory (and Adenitire’s account in this symposium) has been intentionally narrow. As I explain in the book, the aim of the engagement has not been to debunk Cochrane’s theory, nor to argue that it is any less attractive than pure Meritocratic theories (Fasel 2024, p. 131). Rather, it has been to determine whether sentience-based theories can meet ‘Salaville’s Challenge’: the challenge of developing a fundamental rights approach that extends fundamental rights to animals in a way that does not undermine th (...truncated)