•  1801
    Materialism and the Moral Status of Animals
    Philosophical Quarterly 72 (4): 795-815. 2022.
    Consciousness has an important role in ethics: when a being consciously experiences the frustration or satisfaction of its interests, those interests deserve higher moral priority than those of a behaviourally similar but non-conscious being. I consider the relationship between this ethical role and an a posteriori (or “type-B”) materialist solution to the mind-body problem. It is hard to avoid the conclusion that, if type-B materialism is correct, then the reference of the concept of phenomenal…Read more
  •  1759
    Science and Policy in Extremis: The UK’s Initial Response to COVID-19
    European Journal for Philosophy of Science 11 (3): 90. 2021.
    Drawing on the SAGE minutes and other documents, I consider the wider lessons for norms of scientific advising that can be learned from the UK’s initial response to coronavirus in the period January-March 2020, when an initial strategy that planned to avoid total suppression of transmission was abruptly replaced by an aggressive suppression strategy. I introduce a distinction between “normatively light advice”, in which no specific policy option is recommended, and “normatively heavy advice” tha…Read more
  •  1365
    How Should We Study Animal Consciousness Scientifically?
    with Donald M. Broom, Heather Browning, Andrew Crump, Simona Ginsburg, Marta Halina, David Harrison, Eva Jablonka, Andrew Y. Lee, François Kammerer, Colin Klein, Victor Lamme, Matthias Michel, Françoise Wemelsfelder, and Oryan Zacks
    Journal of Consciousness Studies 29 (3-4): 8-28. 2022.
    This editorial introduces the Journal of Consciousness Studies special issue on "Animal Consciousness". The 15 contributors and co-editors answer the question "How should we study animal consciousness scientifically?" in 500 words or fewer.
  •  1127
    The Search for Invertebrate Consciousness
    Noûs 56 (1): 133-153. 2022.
    There is no agreement on whether any invertebrates are conscious and no agreement on a methodology that could settle the issue. How can the debate move forward? I distinguish three broad types of approach: theory-heavy, theory-neutral and theory-light. Theory-heavy and theory-neutral approaches face serious problems, motivating a middle path: the theory-light approach. At the core of the theory-light approach is a minimal commitment about the relation between phenomenal consciousness and cogniti…Read more
  •  727
    The Negative View of Natural Selection
    Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences 43 (2): 569-573. 2012.
    An influential argument due to Elliott Sober, subsequently strengthened by Denis Walsh and Joel Pust, moves from plausible premises to the bold conclusion that natural selection cannot explain the traits of individual organisms. If the argument were sound, the explanatory scope of selection would depend, surprisingly, on metaphysical considerations concerning origin essentialism. I show that the Sober-Walsh-Pust argument rests on a flawed counterfactual criterion for explanatory relevance. I fur…Read more
  •  711
    Natural Selection and the Maximization of Fitness
    Biological Reviews 91 (3): 712-727. 2016.
    The notion that natural selection is a process of fitness maximization gets a bad press in population genetics, yet in other areas of biology the view that organisms behave as if attempting to maximize their fitness remains widespread. Here I critically appraise the prospects for reconciliation. I first distinguish four varieties of fitness maximization. I then examine two recent developments that may appear to vindicate at least one of these varieties. The first is the ‘new’ interpretation of F…Read more
  •  660
    In debates about animal sentience, the precautionary principle is often invoked. The idea is that when the evidence of sentience is inconclusive, we should “give the animal the benefit of the doubt” or “err on the side of caution” in formulating animal protection legislation. Yet there remains confusion as to whether it is appropriate to apply the precautionary principle in this context, and, if so, what “applying the precautionary principle” means in practice regarding the burden of proof for a…Read more
  •  644
    Should Animal Welfare Be Defined in Terms of Consciousness?
    Philosophy of Science 89 (5): 1114-1123. 2022.
    Definitions of animal welfare often invoke consciousness or sentience. Marian Stamp Dawkins has argued that to define animal welfare this way is a mistake. In Dawkins’s alternative view, an animal with good welfare is one that is healthy and “has what it wants.” The dispute highlights a source of strain on the concept of animal welfare: consciousness-involving definitions are better able to capture the normative significance of welfare, whereas consciousness-free definitions facilitate the valid…Read more
  •  642
    Toolmaking and the Evolution of Normative Cognition
    Biology and Philosophy 36 (1): 1-26. 2021.
    We are all guided by thousands of norms, but how did our capacity for normative cognition evolve? I propose there is a deep but neglected link between normative cognition and practical skill. In modern humans, complex motor skills and craft skills, such as toolmaking, are guided by internally represented norms of correct performance. Moreover, it is plausible that core components of human normative cognition evolved as a solution to the distinctive problems of transmitting complex motor skills a…Read more
  •  617
    The Philosophy of Social Evolution
    Oxford University Press. 2017.
    From mitochondria to meerkats, the natural world is full of spectacular examples of social behaviour. In the early 1960s W. D. Hamilton changed the way we think about how such behaviour evolves. He introduced three key innovations - now known as Hamilton's rule, kin selection, and inclusive fitness - and his pioneering work kick-started a research program now known as social evolution theory. This is a book about the philosophical foundations and future prospects of that program. [Note: only the…Read more
  •  570
    Emotionless Animals? Constructionist Theories of Emotion Beyond the Human Case
    Proceedings of the Aristotelian Society. forthcoming.
    Could emotions be a uniquely human phenomenon? One prominent theory in emotion science, Lisa Feldman Barrett’s “Theory of Constructed Emotion” (TCE), suggests they might be. The source of the sceptical challenge is that TCE links emotions to abstract concepts tracking socio-normative expectations, and other animals are unlikely to have such concepts. Barrett’s own response to the sceptical challenge is to relativize emotion to the perspective of an interpreter, but this is unpromising. A more pr…Read more
  •  565
    This is an edited transcript of a lecture given at the LSE in March 2023. The lecture introduces the “meaning of life” question via Tolstoy’s Confession, then considers the strengths and limitations of religious and secular answers to the question.
  •  561
    Animal Cognition and Human Values
    Philosophy of Science 85 (5): 1026-1037. 2018.
    Animal welfare scientists face an acute version of the problem of inductive risk, since they must choose whether to affirm attributions of mental states to animals in advisory contexts, knowing their decisions hold consequences for animal welfare. In such contexts, the burden of proof should be sensitive to the consequences of error, but a framework for setting appropriate burdens of proof is lacking. Through reflection on two cases—pain and cognitive enrichment—I arrive at a tentative framework…Read more
  •  529
    When faced with an urgent and credible threat of grave harm, we should take proportionate precautions. This maxim captures the core commitments of the “precautionary principle”. But what is it for a precaution to be “proportionate”? I construct an account of proportionality (the “ARCANE” account) that consists of five fundamental conditions (absolute rights compatibility, reasonable compensation, consistency, adequacy and non- excessiveness) and a tie-breaker (efficiency). I apply this account t…Read more
  •  516
    Global Workspace Theory and Animal Consciousness
    Philosophical Topics 48 (1): 21-37. 2020.
    Peter Carruthers has recently argued for a surprising conditional: if a global workspace theory of phenomenal consciousness is both correct and fully reductive, then there are no substantive facts to discover about phenomenal consciousness in nonhuman animals. I present two problems for this conditional. First, it rests on an odd double-standard about the ordinary concept of phenomenal consciousness: its intuitive non-gradability is taken to be unchallengeable by future scientific developments, …Read more
  •  496
    Propositional Content in Signalling Systems
    Philosophical Studies 171 (3): 493-512. 2014.
    Skyrms, building on the work of Dretske, has recently developed a novel information-theoretic account of propositional content in simple signalling systems. Information-theoretic accounts of content traditionally struggle to accommodate the possibility of misrepresentation, and I show that Skyrms’s account is no exception. I proceed to argue, however, that a modified version of Skyrms’s account can overcome this problem. On my proposed account, the propositional content of a signal is determined…Read more
  •  490
    Dimensions of Animal Consciousness
    with Alexandra K. Schnell and Nicola S. Clayton
    Trends in Cognitive Sciences 24 (10): 789-801. 2020.
    How does consciousness vary across the animal kingdom? Are some animals ‘more conscious’ than others? This article presents a multidimensional framework for understanding interspecies variation in states of consciousness. The framework distinguishes five key dimensions of variation: perceptual richness, evaluative richness, integration at a time, integration across time, and self-consciousness. For each dimension, existing experiments that bear on it are reviewed and future experiments are sugge…Read more
  •  484
    Neural Organoids and the Precautionary Principle
    American Journal of Bioethics 21 (1): 56-58. 2021.
    Human neural organoid research is advancing rapidly. As Greely notes in the target article, this progress presents an “onrushing ethical dilemma.” We can’t rule out the possibility that suff...
  •  478
    Sentience is the capacity to have feelings, such as feelings of pain, pleasure, hunger, thirst, warmth, joy, comfort and excitement. It is not simply the capacity to feel pain, but feelings of pain, distress or harm, broadly understood, have a special significance for animal welfare law. Drawing on over 300 scientific studies, we evaluate the evidence of sentience in two groups of invertebrate animals: the cephalopod molluscs or, for short, cephalopods (including octopods, squid and cuttlefish) …Read more
  •  475
    Kin Selection, Group Selection, and the Varieties of Population Structure
    British Journal for the Philosophy of Science 71 (1): 259-286. 2020.
    Various results show the ‘formal equivalence’ of kin and group selectionist methodologies, but this does not preclude there being a real and useful distinction between kin and group selection processes. I distinguish individual- and population-centred approaches to drawing such a distinction, and I proceed to develop the latter. On the account I advance, the differences between kin and group selection are differences of degree in the structural properties of populations. A spatial metaphor provi…Read more
  •  469
    Gene Mobility and the Concept of Relatedness
    Biology and Philosophy 29 (4): 445-476. 2014.
    Cooperation is rife in the microbial world, yet our best current theories of the evolution of cooperation were developed with multicellular animals in mind. Hamilton’s theory of inclusive fitness is an important case in point: applying the theory in a microbial setting is far from straightforward, as social evolution in microbes has a number of distinctive features that the theory was never intended to capture. In this article, I focus on the conceptual challenges posed by the project of extendi…Read more
  •  452
    Samir Okasha and Ken Binmore (eds), Evolution and rationality: Decisions, cooperation, and strategic behaviour (review)
    British Journal for the Philosophy of Science 64 (3): 669-673. 2013.
    Evolution and Rationality marks the end of a three-year project, ‘Evolution, Cooperation, and Rationality’, directed at the University of Bristol by the book’s editors, Samir Okasha and Ken Binmore. The collection draws together the editors’ pick of the papers delivered at the conferences the project hosted, and covers a wide range of topics at the intersection of evolutionary theory and the social sciences. It is a splendid anthology: timely, interdisciplinary, thematically cohesive, and full o…Read more
  •  450
    Robust processes and teleological language
    European Journal for Philosophy of Science 2 (3): 299-312. 2012.
    I consider some hitherto unexplored examples of teleological language in the sciences. In explicating these examples, I aim to show (a) that such language is not the sole preserve of the biological sciences, and (b) that not all such talk is reducible to the ascription of functions. In chemistry and biochemistry, scientists explaining molecular rearrangements and protein folding talk informally of molecules rearranging “in order to” maximize stability. Evolutionary biologists, meanwhile, often s…Read more
  •  440
    When Is a Brain Organoid a Sentience Candidate?
    Molecular Psychology. forthcoming.
    It would be unwise to dismiss the possibility of human brain organoids developing sentience. However, scepticism about this idea is appropriate when considering current organoids. It is a point of consensus that a brainstem-dead human is not sentient, and current organoids lack a functioning brainstem. There are nonetheless troubling early warning signs, suggesting organoid research may create forms of sentience in the near future. To err on the side of caution, researchers with very different v…Read more
  •  437
    How Cooperation Became the Norm (review)
    Biology and Philosophy 29 (3): 433-444. 2014.
    Most of the contributions to Cooperation and Its Evolution grapple with the distinctive challenges presented by the project of explaining human sociality. Many of these puzzles have a ‘chicken and egg’ character: our virtually unparalleled capacity for large-scale cooperation is the product of psychological, behavioural, and demographic changes in our recent evolutionary history, and these changes are linked by complex patterns of reciprocal dependence. There is much we do not yet understand abo…Read more
  •  424
    Fitness Maximization
    In Richard Joyce (ed.), The Routledge Handbook of Evolution and Philosophy, Routledge. pp. 49-63. 2016.
    Is there any way to reconcile the adaptationist’s image of natural selection as an engine of optimality with the more complex image of its dynamics we get from population genetics? This has long been an important strand in the controversy surrounding adaptationism, yet debate has been hampered by a tendency to conflate various different ways of thinking about maximization. Here I distinguish four varieties of maximization principle. I then discuss the logical relations between these varieties, a…Read more
  •  420
    Joint know-how
    Philosophical Studies 176 (12). 2019.
    When two agents engage in a joint action, such as rowing together, they exercise joint know-how. But what is the relationship between the joint know-how of the two agents and the know-how each agent possesses individually? I construct an “active mutual enablement” account of this relationship, according to which joint know-how arises when each agent knows how to predict, monitor, and make failure-averting adjustments in response to the behaviour of the other agent, while actively enabling the ot…Read more
  •  409
    On the 'Simulation Argument' and Selective Scepticism
    Erkenntnis 78 (1): 95-107. 2013.
    Nick Bostrom’s ‘Simulation Argument’ purports to show that, unless we are confident that advanced ‘posthuman’ civilizations are either extremely rare or extremely rarely interested in running simulations of their own ancestors, we should assign significant credence to the hypothesis that we are simulated. I argue that Bostrom does not succeed in grounding this constraint on credence. I first show that the Simulation Argument requires a curious form of selective scepticism, for it presupposes tha…Read more
  •  395
    Agents and Goals in Evolution, by Samir Okasha (review)
    Mind 128 (512): 1408-1416. 2019.
    In this essay review of Samir Okasha's Agents and Goals in Evolution, I reflect on the rationale for agential thinking in biology, and consider whether the rationale is the same for genes as for organisms. I also discuss Okasha's ingenious examples of the evolution of irrational behaviour, and in particular the evolution of violations of the "independence axiom" of rational choice theory. These examples rely on a crucial distinction between aggregate and idiosyncratic risk.
  •  388
    Christian List has recently constructed a novel formal framework for representing the relationship between free will and determinism. At its core is a distinction between physical and agential levels of description. List has argued that, since the consequence argument cannot be reconstructed within this framework, the consequence argument rests on a ‘category mistake’: an illicit conflation of the physical and agential levels. I show that an expanded version of List’s framework allows the constr…Read more