Which beings matter morally, and to what extent do different beings matter? Perennial ethical questions such as these lie at the heart of the concept of moral status. The recent volume Rethinking Moral Status (2021, Oxford University Press), edited by Steve Clarke, Hazem Zohny, and Julian Savulescu, revisits and reexamines these questions in great depth. By focusing on the ethical challenges raised by emerging technologies and bringing together a group of prominent ethicists to reflect on them, this work serves as an important philosophical forum that casts longstanding ethical concepts in a new light.
The book is divided into two main parts: part I, ‘The Idea of Moral Status,’ and part II, ‘Specific Issues about Moral Status.’ Part I covers theoretical, conceptual, and foundational questions regarding moral status. Part II relates theorizing about moral status to particular ethical issues such as the treatment of entities like nonhuman animals, chimeras (human–animal hybrids), cognitively enhanced animals, post-humans, human brain organoids, advanced AI systems, and uploaded minds. Both parts are preceded by an illuminating introductory chapter by Clarke and Savulescu, which provides a concise yet detailed overview of the concept of moral status and the key discussion points, particularly in the context of bioethics and technology ethics.
Part I of the book underscores the multifaceted nature of moral status, with each chapter examining different aspects of the concept. By and large, the contributions in part I converge on the view that a being has moral status just in case it matters morally in its own right, with some authors (e.g., David DeGrazia and Frances Kamm) also defending or considering a stronger conception on which the duties owed to a being with moral status must necessarily exist for the sake of that being. Additionally, the contributing authors generally seem to agree on the following key points: (1) being human is neither necessary nor sufficient for moral status, (2) certain cognitive capacities (e.g., phenomenal consciousness, sentience, self-awareness, and/or rationality, depending on the particular view) are at least sufficient for moral status, and (3) the moral status of some beings is higher than that of others (e.g., human adults with sentience and higher-order cognitive capacities compared to merely sentient animals). Nevertheless, each author also contributes their own unique perspectives and discussion points, which are worth highlighting.
Jeff McMahan, David DeGrazia, and Ingmar Persson each focus on sentience in their respective chapters. McMahan considers how psychological connectedness impacts one's moral status in relation to suffering (e.g., whether the suffering of individuals that permanently lack psychological connections to themselves would matter morally just as much as the equivalent suffering of a person, which McMahan disputes). DeGrazia outlines the main assumptions of his sentient interests-based account of moral status and rights and relates his model to specific issues in applied ethics. Persson uses sentience and other related moral properties to illustrate the potential endless variability of moral status, leading him to the conclusion that ethical frameworks should prioritize the concept of moral significance over that of moral status.
Joshua Shepherd's chapter, in contrast, considers the significance of phenomenal consciousness more generally, proposing the richness of mental life (‘phenomenal richness’) as a criterion for moral status and exploring its practical implications in detail. The chapters by Frances Kamm and Elizabeth Harman are unique in their emphasis on the temporal dimensions of moral status and harm – key aspects in ethical debates on abortion and future generations. While Kamm engages with the famous nonidentity problem by Derek Parfit, arguing against Parfit's ‘No Difference View,’ Harman defends the ‘Ever Conscious View’ of moral status, according to which a being has moral status if it ever was or will be conscious. A counterintuitive implication of Harman's view – albeit one she chooses to accept – is that two qualitatively identical beings could have different moral status if one was conscious for even a moment while the other was not.
Udo Schuklenk stands out by critiquing rather than defending the standard cognitive capacities criteria for moral status as overly anthropocentric – although his chapter gives little consideration to justifications of these criteria, which typically aim to be species-neutral. Lastly, Thomas Douglas addresses the important question of whether changes to one's moral status – such as through cognitive enhancement or disenhancement – could be good or bad for the individual, drawing out implications based on different accounts of value.
In summary, part I offers valuable insights into various theoretical and conceptual aspects of moral status, with a predominant focus on cognitive capacities as the relevant foundation, rather than, for example, on moral relationships more commonly discussed in the Continental tradition of philosophy. Nevertheless, the contributing authors go beyond simply revisiting familiar debates on which capacities matter morally, instead aiming to uncover other significant dimensions of moral status. In particular, the chapters by McMahan, Kamm, Harman, and Persson stand out in terms of their philosophical depth and rigor.
Part II transitions from the theoretical foundations of moral status to the exploration of particular ethical issues. While cognitive capacities remain a central theme, subtle variations in approach emerge within part II, which will be highlighted in the discussion that follows.
The first three chapters in part II, written respectively by Ruth Faden et al., Jason Scott Robert and Françoise Baylis, and Sarah Chan, largely focus on the ethics of the creation of human–nonhuman chimeras. The goals of chimera research include developing models for studying human diseases, testing drug efficacy, and producing human-compatible organs for transplantation. The chapter by Faden et al., drawing on sentience and intellectual faculties as key criteria, underscores the need for a robust and actionable hierarchical theory of moral status suitable for informing policy decisions. This suggestion aligns with scalar conceptions of moral status, as chimera research may give rise to beings with moral properties instantiated to varying degrees, arguably resulting in new quantitative dimensions of moral status.
Robert and Baylis examine both scientific and philosophical issues concerning chimeras, arguing that much of the opposition stems from the fact that properties-based approaches to moral status result in what they term ‘inexorable moral confusion.’ As an alternative, they propose the social–relational approach advocated by Mark Coeckelbergh and David Gunkel in the context of robot and animal ethics. While intriguing, the focus on social relationships could be critiqued as necessarily incomplete, since it risks overlooking important ‘internal’ ethical aspects – such as the possibility noted by Faden et al. of chimerism in the brain leading to new morally relevant sensations.
Chan's chapter reflects on a range of important issues concerning moral status, including moral status enhancement, the difficulty in establishing standards for moral status comparisons, and the ethical implications of species-altering enhancements. Chan also offers an intriguing perspective on Robert and Baylis's concept of inexorable moral confusion, suggesting that the creation of post-persons through human enhancement may itself be a key to resolving this confusion.
The three ‘middle’ chapters of part II – authored respectively by Benjamin Sachs, Rachell Powell et al., and Julian Koplin et al. – do not converge on a single particular issue, instead addressing unique ethical concerns within the volume. Sachs's thought-provoking chapter explores the vital relationship between moral and legal status, arguing that while animals can be wronged, this does not straightforwardly justify criminalizing actions that harm them. Instead, Sachs maintains that if the law contains features that facilitate the wronging of animals, lawmakers ought to amend the law to remove those features.
Powell et al. delve into the important topic of human biases in moral status ascriptions, noting that the capacity for welfare is widespread and ancient from an evolutionarily perspective, yet human emotions like fear and disgust often distort our perceptions of other beings. The authors highlight the human ‘empathy gap’ toward invertebrates as a significant example that obstructs moral progress. Shifting to another pressing issue, Koplin et al. examine the moral status of human brain organoids, applying the sentient interests-based approach and arguing that the ethical principles governing animal research provide a more suitable starting point for the treatment of sentient organoids than do the existing frameworks for human tissue research.
The final three chapters turn to the moral status of artificial entities such as robots. Walter Sinnott-Armstrong and Vincent Conitzer present a unique multicriterial framework, arguing that robots could possess certain moral rights – such as the right to freedom – even without being phenomenally conscious. For Sinnott-Armstrong and Conitzer, intelligence, access consciousness (i.e., awareness of information for reasoning and action), free will, and understanding in a purely functional sense are sufficient to confer a degree of moral status. This stands in contrast to the chapter by David Lawrence and John Harris, who emphasize the centrality of self-consciousness for moral agency and argue that the principles guiding our treatment of great apes could serve as a model for our responsibilities toward artificial moral agents once they emerge.
The volume closes with Carl Shulman and Nick Bostrom's impressive discussion of the moral status of digital minds. Shulman and Bostrom consider the possibility of artificial ‘super-beneficiaries’ – digital minds that are, individually or collectively, superhumanly efficient at generating welfare. Their thought-provoking analysis suggests that digital welfare could, in theory, vastly surpass human welfare across multiple quantitative dimensions, including reproductive capacity, cost of living, subjective processing speed, hedonic skew and range, mind scale, and others, with profound implications for moral status.
Overall, part II examines numerous emerging ethical issues in great detail while also revisiting several longstanding ones. While the focus on cognitive capacities is retained (with the possible exception of Robert and Baylis's chapter), some contributions in this part are noteworthy for their advocacy of more inclusive ethical approaches. These include Sinnott-Armstrong and Conitzer's emphasis on the functional capabilities of robots and Powell et al.'s exploration of the moral status of invertebrates. Similar to part I, the contributors in part II generally adopt a nuanced scalar conception of moral status and advocate for precautionary ethical frameworks to address potentially transformative future challenges, such as cognitive enhancement, chimera research, and the moral status of robots.
In conclusion, Rethinking Moral Status is a timely and significant contribution to the theory and practice of moral status. The volume is well-structured and balanced, featuring high-quality contributions from renowned scholars who tackle both the traditional and contemporary ethical issues with philosophical rigor, clarity, and interdisciplinary depth. As a whole, the collection reinforces the ongoing philosophical shift away from anthropocentric ethics, advancing a more refined, inclusive, and rationally defensible understanding of moral status. The insights it offers are valuable not only to academic researchers but also to policymakers navigating the ethical challenges of a rapidly evolving world.
