Sean Valles’ Philosophy of Population Health marks an important contribution to the analysis of philosophical issues relevant to a broad range of issues at the interface of population and public health. The book exemplifies the constructive contributions scholars from philosophy of science and ethics can make to advance our understanding core issues in this area, historically dominated by concern for medicine and the delivery of health care to individuals. Professor Valles’ contribution joins the work of Alex Broadbent and the philosophy of epidemiology, and the work of Angus Dawson and Marcel Verweij and Ruth Faden and Madison Powers and others in public health ethics.
The stated purpose of the book is to advance a population health framework and spark a dialogue between philosophy and population health. The book succeeds in achieving both aims. In the introduction, Professor Valles notes that unlike in previous philosophical work where “we typically find a combination of individually avoidable errors dubious shortcuts and ill designed methods. All the while philosophers of science and medicine still tend to have an abiding respect and appreciation for the science/medicine, critiquing in the hopes of making things better. When scrutinizing the philosophical underpinnings of a new interdisciplinary program such as in my previous work on evolutionary medicine and personalized genomic medicine I’ve come to expect extensive, if not fatal, problems. Imagine my surprise at encountering population health science and finding nothing really fundamentally broken. What I found instead was a field that has many debates and unsettled theoretical and practical questions that remain to be sorted out.” (3) This optimistic perspective pervades the book which is quite useful in sorting out some of the philosophical issues at the interface of the philosophy of medicine, philosophy of science and ethics relevant population health.
The book is well organized and laid out. The introductory chapter provides a blueprint of a philosophy of and for population health. A brief overview commences with a broad definition of public health and population health and explains how the aims and methods of these are distinct from clinical medicine and healthcare. The core philosophical issues and arguments to be addressed in each chapter are outlined, as are the methodological and normative commitments of the author.
The book is divided into three parts: Part 1: What should health mean in population health science; Part 2: What causes and effects matter most in population health; Part 3: How can population health science better promote equity health equity. Each section contains chapters which systematically address key concepts and engage deeply with the current literature. The chapters explore key epistemological, ethical and metaphysical issues related to the concept of health, a social concept of health, health as a life course trajectory and how accounts of causation expand the boundaries of population health and how causation can be understood in population health. Part 3 brings things together through the lens of ethics and evidence. Each of the chapters ends with a case study that illustrates the issues that are raised in the chapter. The case studies are exceptionally well chosen as they are drawn from contemporary events and touch on Indigenous health, environmental issues, communicable disease and migrant health.
What is most notable about this book is the way that the author skillfully and with great nuance explicates and distils the arguments of the many debates about population health and the determinants of health. He successfully and clearly lays out some of the key boundary issues concerning the scope and range of population health, summarizes and brings coherence to the many debates concerning the nature of causation, and sympathetically navigates the sometimes bitter arguments between public health and health care. The discussion of health equity is noteworthy in bringing clarity to the discussions of how equity is defined in health and its relationship to theories of justice.
Professor Valles is committed to an expansive concept of health and argues for the irreducible role that social forces play in the creation of health. He also argues for a life course trajectory concept of health. He is unabashedly supportive of pluralism in our metaphysical, empirical, ethical and methodological engagement with population health. Professor Valles provides an update and spirited defense of the 1946 World Health Organization definition of health, which has come under significant criticism in recent years. His reconstructed argument yields a new definition of health as a life course trajectory of complete well-being in a social context.
This concluding chapter argues for the overarching need for a spirit of humility and collaboration. As Valles notes, power relationships take on a special importance for population health science. He argues further that humility is key to population health sciences success: “Humility is needed in three areas: an overarching epistemic humility recognizing that no single person or perspective can have a full understanding of population health; intersectoral humility recognizing that no sector of society (government, health care etc) is elevated above the others; and a disciplinary humility recognizing that no contributing discipline in interdisciplinary population health science is elevated above the others.” (181)
Professor Valles has skillfully drawn together and woven into a coherent framework a diverse set of literature dating back to the 19th century and the origins of social medicine. He does justice to the literature and acknowledges the importance of integrating elements of modern preventive medicine with a sustained explication of the work of Geoffrey Rose. He also highlights the significance of modern frameworks such as the WHO Social Determinants of Health Commission.
I believe that some readers, no doubt wed to a particular theory, may take issue with arguments raised in the discussion of causation. Professor Valles contrasts his approach with that of Alex Broadbent’s as set out in his book Philosophy of Epidemiology. Professor Valles endorses the notion of fundamental cause theory as a particularly promising contribution to population health science. His endorsement of this theory should stimulate significant debate. Similarly, I think there may be scholars committed to a particular theory of justice and of particular interpretations of health equity that may resist the pluralism that he endorses.
I highly recommend this book to scholars, public health and health care practitioners, policy makers and the general reader interested in population health. The book is an excellent complimentary source to Population Health Science by Keyes and Galea, for those interested in a more technical approach to population health. Few books I know of so skillfully and effortlessly employ concepts form the philosophy of science, philosophy of medicine, and ethics. I hope this book finds its way into undergraduate and graduate courses in schools of public health, faculties of medicine, and into graduate courses in philosophy of science and philosophy of medicine. I hope that this book stimulates the creation of new courses in philosophy of population and public health. Many curricula at schools of public health leave little room for engagement with the wide range of diverse philosophical views relevant to their field. I believe that this book would help provide a sound foundation for early 21st century graduate students struggling with the deeper concepts raised by the practice of public health and population health.
Dalla Lana School of Public Health
Bridgepoint Collaboratory for Research and Innovation
Lunenfeld Tanenbaum Research Institute, Sinai Health Systems
University of Toronto