Philippe Huneman’s Death: Perspectives from the Philosophy of Biology offers a remarkably comprehensive exploration of the biology of death through a philosophical lens. Its ambitious aim is, in Huneman’s own words, ‘to confront philosophical questions about death […] with the biology of death’ (p. 31). Whether it fully achieves this bold objective or not, the book undeniably addresses a curious and long-overlooked gap in the philosophy of biology.

The book begins with a puzzle. Philosophers have long been preoccupied with the nature and value of death. Should we fear death? Is death bad? How should we comport ourselves in the face of our own inevitable demise? Yet, with few exceptions, philosophers have ignored the biology of death—its evolution and mechanisms. How, physiologically, do we die? Why, from an evolutionary perspective, must we die?

One might argue that the biology of death is strictly irrelevant to questions about what death should mean for us, but a little reflection shows that this is manifestly false. If death exists ‘for the good of the species’ or if it is an inevitable trade-off for a fruitful life, this would be relevant to philosophical theorizing about its value, even if it doesn’t ultimately determine the stance one adopts.

Understanding the how and why of death is also necessary for addressing scientific, legal, and ethical problems associated with death. What is the proper definition of death? What are the correct criteria for determining death? When does the process of dying begin, for example, in terminal illness? If an organism is cryogenically frozen and later reanimated, was it ever truly dead? Such questions are central to the emerging science of longevity.

The book splits neatly into two parts: how do we die, and why do we die? Part 1 (chapters 2–6) addresses the ‘how’ of death. However, it is not an up-to-date scientific overview. Instead—and I think more valuably—it offers a historical analysis of how death became a proper object of scientific inquiry. Huneman provides a precise reconstruction of the epistemic context that prepared scientists to investigate rigorously how death occurs. In his view, death became an object of scientific study with the 1801 publication of Bichat’s Recherches physiologiques sur la vie et la mort.

Prior to Bichat, Huneman argues, death—at least in the European world—was typically conceived from one of two perspectives. The first was the Christian point of view, in which death is an instantaneous separation of soul and body. The second, more scientifically respected view, held that death resulted from the progressive deterioration of vital organs—a matter of generic wear and tear. Neither approach lent itself to a rigorous experimental science of death. To establish such a science, death needed to possess a richer empirical structure: a mechanism. Bichat provided that mechanism.

Chapter 2 outlines the intellectual milieu in which Bichat worked. His core questions were: what concepts are required to capture the specificity of living organisms and what methods are appropriate for studying them? Neither the mechanists, like Descartes, nor the vitalists, like Haller and Stahl, offered a satisfying answer. Mechanists made no fundamental distinction between living and non-living matter, while vitalists enveloped the study of life in impenetrable mystery. Bichat resolved this dilemma by focusing on the problem of death. Paradoxically, as Huneman explains, the study of death laid the foundations for the science of life.

Chapter 3 examines how Bichat articulated the science of physiology, elevating the study of biological function to a precise experimental discipline, one that paralleled the precision of anatomy. He also introduced an influential definition of life: life is the set of functions that resist death. Chapter 4 explores Bichat’s distinction between organic and animal functions, emphasizing the latter’s historicity. While organic functions are mostly fixed at birth, animal functions—shaped by habit, learning, or education—are more susceptible to variation and change.

This discussion culminates in chapter 5, where Huneman describes Bichat’s monumental intellectual shift. Death was no longer understood as the instantaneous separation of soul and body, nor as the endpoint of the gradual deterioration of vital organs. Instead, death was seen as the result of a cascading series of organ failures—heart, lungs, and brain—a sequence that could be experimentally traced. Through this lens, Bichat transformed death into an object of scientific knowledge. His experimental approach to death also deepened his understanding of life’s distinctive ‘circular causality’, a concept Kant put to work memorably in his third Critique.

The final chapter of part 1, chapter 6, demonstrates how later scientists, such as Claude Bernard, refined Bichat’s physiological principles with greater rigour. However, there remained a critical gap in this new-found experimental tradition: the absence of an evolutionary perspective. For Bernard, death remained a brute fact. Without an evolutionary framework, it was impossible for him to ask the more fundamental question: why do we die?

Part 2 (chapters 7–15) turns to the evolutionary question. Chapter 7 shows how, prior to Darwin, philosophers from Plato to Schopenhauer relied on a ‘providentialist metaphysics’ to make sense of death. They viewed it as, in some sense, ‘the price paid for the benefit of life’ (p. 178). This sets the stage for an intriguing question: did Darwinist thinking replace providential thinking or, rather, provide it with a scientific grounding?

Chapter 8 outlines two theories that emerged in the 1950s, which represent the cornerstone of the modern evolutionary perspective on death: Peter Medawar’s mutation accumulation theory and George Williams’s antagonistic pleiotropy theory. Medawar posits that death results from a basic principle of evolution—the strength of selection declines with age. For example, a gene mutation causing a severe disability at an early age would be quickly eradicated by selection, while a mutation with late-life effects might persist in the population simply because, in the wild, relatively few individuals live long enough to experience its damaging consequences. The accumulation of such mutations would be catastrophic for those individuals that happen to live long lives. Williams developed Medawar’s account further with his theory of antagonistic pleiotropy, arguing that genes offering benefits early in life—even if they are harmful later—are favoured by natural selection. For Williams, death is a trade-off for improved viability and fecundity in early life.

The next two chapters, spanning just over 100 pages, explore conceptual and epistemic aspects of death. Huneman notes that many evolutionary theories of death could be more precisely described as theories of senescence, which concern the gradual deterioration of vital functions as organisms age. However, the idea of senescence is often intuitively defined and varies among researchers. Moreover, distinctions between aging, senescence, and lifespan are sometimes unclear. In chapter 9, Huneman seeks to clarify these concepts and provides an overview of evidence supporting evolutionary theories of senescence.

Chapter 10 surveys the epistemic challenges of testing evolutionary theories of death. Huneman reviews various experimental approaches, such as lab studies and fieldwork, highlighting the complexities of coordinating theory and evidence. For example, he notes that lab and field studies often clash, complicating efforts to evaluate competing theories. The chapter concludes with Huneman’s cautious recommendation for pluralism in explanations of death.

Evolutionary theories of aging and death are often expressed, even in scholarly literature, via metaphors (for example, Garson [2021]). Evolutionary theorists often talk of trade-offs, the ‘decreasing force of selection’, or the idea that natural selection ‘prefers’ the young over the aged. This raises philosophical questions about articulating the ontology of death and related phenomena more exactly. In chapter 11, Huneman focuses on articulating the notion(s) of trade-offs. He also considers the disposable soma theory, which views death as resulting from a compromise in the way organisms allocate resources between repair and reproduction.

One of the earliest evolutionary theories of death, owing to August Weismann, proposes that natural selection equipped organisms with a ‘death programme’ to prevent older generations from consuming resources better allocated to the young. Framed in group-selectionist terms, this theory suggests that while death is detrimental to the individual, it benefits the group. With the resurgence of group-selectionist thinking in biology, the idea of a death programme has regained attention (for example, Longo et al. [2005]). In chapter 12, Huneman explores the nuances and potential implications of this concept, particularly for longevity research.

Chapter 13 further articulates and defends this provocative theory, echoing Weismann’s early speculation that death is, in some sense, ‘by design’. While death doesn’t inherently benefit the individual, it suggests an altruistic trade-off shaped by group selection—similar to the honeybee’s stinger. Huneman explores philosophical debates on kin selection versus group selection, arguing that, contrary to the ‘equivalence thesis’, they are distinct and that group selection likely plays a larger role. He also cites recent experimental studies, such as research on fruit flies exhibiting the ‘Smurf phenotype’, which support the idea of programmed death.

In chapter 14, Huneman examines broader implications of the group-selectionist model. He considers how this perspective connects death to social structures, ecological balance, and the emergence of multicellularity. Huneman reflects on whether modern evolutionary reasoning has, perhaps unwittingly, resurrected providentialist views of death that it once sought to replace. Chapter 15 ends with a short philosophical conclusion.

Death is an extraordinary book that provides a starting point for a field of study philosophers of biology have largely overlooked. Huneman exhibits an exceptional ability to weave together the history of the science of death and the cutting-edge science of its mechanisms. This is particularly impressive given how technically demanding contemporary theorizing on the topic is. He also defends a frankly startling thesis that should drive conversation. We can only hope that this book stimulates a new generation of philosophers of biology to dive into this important topic.

Yet, it seems to me there’s an important limitation—one that I think may be inevitable in a book of this scale and ambition. At the outset of the book, Huneman is clear about his intention to confront the philosophy of death with the biology of death. A reader might, then, reasonably expect a powerful pay-off for metaphysicians of a more traditional stripe who ponder the meaning and value of death, as well as for bioethicists who consider the correct definition and criteria of death.

By the end of the book, however, such a reader may feel disappointed, as those broader philosophical consequences are scarcely broached. Regarding how one should think about and behave toward death, Huneman admits: ‘I have no idea about the role the idea of death should play’ (p. 490). But, surely, the group-selectionist viewpoint advanced here lends itself quite naturally to a neo-providentialist reading. If death is, in some sense, good for the group, that fact should serve as a starting point for philosophical reflection on what it means for the living, as well the value we place on scientific projects such as longevity research.

Perhaps the most tantalizing suggestion for traditional philosophy is that, as Huneman puts it, ‘a major lesson of this examination is that the metaphysical weight of death is somehow lightened’ (p. 393). Contrary to the view that death is a necessary feature of life, Huneman argues that death is a contingent fact of nature—much like zebra stripes or cleft chins. If the history of life had taken a different turn, humanity might have been immortal (short of external accidents such as predation, poisoning, and so forth). Thus, to the extent that one might have thought, following Hegel, that death is a necessary feature of life (as Huneman describes Hegel’s view, ‘the living individual has to die to let the universal rise’) and sought to justify it as the inevitable trade-off for the gift of life, one would be mistaken.

We can only hope that Huneman may someday turn his extraordinary capacity to writing a shorter, companion volume—one that sheds some detours, historical nuances, and technical expositions—to take on those traditional metaphysical and ethical questions more directly.

Justin Garson
Hunter College
and
The Graduate Center
jgarson@hunter.cuny.edu

References

Garson, J. [2021]: ‘Ageing and the Goal of Evolution’, History and Philosophy of the Life Sciences, 43, available at .

Longo, V. D., Mitteldorf, J. and Skulachev, V. P. [2005]: ‘Programmed and Altruistic Ageing’, Nature Reviews Genetics, 6, pp. 866–72.