Human nature is a “super” concept that recurs across lay and scientific theorizing from ancient times to the present day, and it also spans the descriptive and the normative. As such it is a worthy target for philosophical scrutiny. Lucky we are, then, that Elizabeth Hannon and Tim Lewens have edited a terrific volume, Why We Disagree About Human Nature, that brings an interdisciplinary range of leading thinkers offering arguments and reflections on the concept of human nature that amount to a state-of-the-art report on what roles it can, and cannot, play.
What could be more familiar and obvious than the idea that there is such a thing as human nature? Concerns about the idea of human nature emerge, on the one hand, from the embrace of the Darwinian idea that variation is ubiquitous in the natural world and the abandonment of traditional and intuitive ideas of natural essences. If variation is the rule and there are no shared essences, then perhaps there is no human nature to speak of. They emerge, on the other hand, from concerns that attempts to characterize human nature are inevitably normative in their source, consequences, or both; resulting, perhaps, in an oppressive marginalization of difference. More recently, an increasing appreciation of “externalist” explanatory perspectives on human development and evolution have provided additional reasons to worry.
The book begins with an excellent chapter by Lewens that introduces key themes of discussion as well as the contributions of the various chapters, serving as a guide to the rich offerings of the volume. Following that, most of the chapters engage some straightforward philosophy of science questions: what role, if any, can and ought a scientifically informed conception of human nature play in contemporary scientific and philosophical discourse? Given what we now know about human development, evolution, and genetics, is the idea of human nature even coherent?
Edouard Machery defends the continuing usefulness of his own “nomological notion” of human nature: “the set of properties that humans tend to possess as a result of the evolution of their species” (18). “Tend to possess” insists on the human-typicality of the properties that figure as part of human nature, while “as a result of evolution” insists on a biological rather than social or individual learning source.
Machery’s defense of his view is followed by a critique of the nomological account by Grant Ramsey, who defends an alternative “cluster” account. Ramsey criticizes Machery’s account as a “trait bin” account because it divides human traits “into two mutually exclusive bins: the nature category and the other category (containing, say, cultural or learned traits)” (42), while his own “cluster” account proposes that we think of human nature as “the patterns of trait expression over the totality of extant human possible life histories” (49). In Ramsey’s thinking, the variety of human traits that emerge in individual life histories are all expressions of individual nature in various circumstances, and human nature is simply a set of patterns discernible over these individual histories. In Ramsey’s view, then, human nature includes culturally and other developmentally produced patterns across all individual life histories.
The debate here proceeds in familiar philosophical ways, with Machery and Ramsey noting the fit (or failure of fit) of each conception with scientific facts, expert practice, and common sense. Subsequent chapters continue to take up these core philosophical questions, but they also amplify consideration of external (i.e., extragenomic and extraorganismic) determinants of development and evolutionary processes for our thinking about human nature.
In the last few decades a family of perspectives has emerged that attempt to integrate an appreciation of developmental complexity within evolutionary frameworks. These include developmental systems theory, attention to evolved learning capacities, niche construction, and gene-culture coevolutionary theory—perspectives that are all represented here. But while some take these new frameworks to provide the key to more sophisticated and accurate thinking about human nature, others take such complexity as a signal to abandon the notion of human nature altogether.
Karola Stotz and Paul Griffiths align their own “developmental systems theory” account with Ramsey’s rejection of trait bins, but instead of identifying human nature with Ramsey’s “trait cluster,” they suggest identifying it with the myriad and complex developmental processes that, over time and in various environments, give rise to those patterns of traits (66ff). Cecilia Heyes also focuses upon developmental processes, though she focuses upon “the theory of natural pedagogy,” the idea that humans are evolved, “natural” teachers and learners. But unlike a view in which human infants are evolved as “jukeboxes” that search their environment for the parameters that will initiate one or another developmental program, Heyes argues that we ought to view our emerging understanding of natural pedagogy as directing us to “the importance of cultural evolution in shaping human nature” (77). She ultimately proposes identifying human nature with “the set of mechanisms that underlie the manifestation of species typical cognitive and behavioral regularities” (88), where these include epigenetic and culturally evolved mechanisms.
Four additional chapters, guided by some of the same considerations, take attention to processes to indicate that it may be time to abandon serious thinking in terms of human nature. Kim Sterelny, inspired by seminal work from David Hull, proceeds to argue both against recent attempts by Michael Devitt to revive the notion of essence (which would provide a candidate for a species nature) and against attempts like those of Machery or Ramsey to reconstruct the notion of human nature. While he is a proponent of a version of natural pedagogy, he nonetheless thinks that “once we recognize the historical and genealogical nature of species in general and our species in particular …, once we recognize that change over time and variation at a time matter …, it is not clear we need a theory of human nature” (113).
Kevin Laland and Gillian Brown argue even more pointedly that the concept of human nature is put to multiple incompatible purposes and “is more trouble than it is worth and should be abandoned” (127). As with others in the volume (perhaps especially Stotz and Griffiths, Sterelny, and Christina Toren) their concerns grow out of an intense appreciation of the difficulty of distinguishing the contributions of biological and environmental determinants when we attend to actual developmental and evolutionary processes.
A turn to process and the proposed abandonment of the idea of human nature is also evident in Toren’s anthropological perspective. She proposes that we do “away with ideas of ‘human nature’ and ‘culture’ as analytical categories” and instead “conceive of all aspects of the world—including, crucially, all dimensions of human being, indeed of all living things, as historically constituted” (173).
Among the skeptics, perhaps the most radical shift to “process” thinking is defended by John Dupré, who suggests a metaphysical reorientation in our thinking about humans from things to processes. He writes that: “A human is not a thing with a fixed set of properties, but a life cycle. I suggest that as such, we are better thought of as processes than as things” (93). This is a radical idea whose implications for thinking about human nature Dupré begins to explore, but important also is that Dupré, like Toren, sees that the challenge of getting people to think and theorize without an entrenched and intuitive notion like human nature is not only in saying what is wrong with it, but in envisaging what the alternatives might be.
Beyond debates over the role of the notion of human nature, another feature of the volume is engagement with the diverse historical and disciplinary contexts in which discussion of human nature finds a home, addressing the how and (as promised!) the why of disagreements. While threads of these discussions occur throughout the papers (e.g., in Stotz and Griffiths’ or Laland and Brown’s connections of debates over human nature with others over the notion of innateness), these threads are most fully developed in chapters by Peter Richerson and Maria Kronfeldner.
Richerson offers a historical survey of ideas of human nature and evolution by way of arguing that appreciation of the extragenetic aspects of human evolution (as in niche construction and in gene-culture co-evolution) requires amending the modern synthesis that married Mendelian genetics with Darwin’s theory of evolution to include a role for (for example), cultural evolution. And Kronfeldner proceeds to trace the history of human-nature thinking from antiquity into the 21st century in order illustrate the way in which “nature” comes to be used and interpreted as authoritative, given a range of historical and disciplinary contexts and contrasts.
These historical and cross-disciplinary perspectives are valuable alongside more theoretical arguments because of the point I made at the outset: Ideas about human nature appear in so many places, doing so much work, that a great deal of conceptual effort is needed to keep them straight and understand their significance. While no book can be the last word on a subject like this, this book gives the latest word, and it should be among the first things to read for those who will carry the discussion forward from here.
