Valles SA. Philosophy of Population Health: Philosophy for a New Public Health Era.

ABSTRACT This book analysis some features and consequences of the emerging field of Population Health Science, which some authors define as Public Health 3.0. It is a mode of reaction against the biomedical model of health which was hegemonic in the twentieth century. It recognizes the World Health Organization’s (WHO) definition of health ‘as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity’, that health is empirically social and most of its determinants are social and economic ones; population health interventions are ethically inseparable from social empowerment and health research and health promotion must, coherently with these ideas, contemplate health as a social phenomenon too. Community-based participatory research is a pressing need for a change in the field of public/population health.

THIS BOOK ANALYSIS SOME FEATURES and consequences of the emerging field of Population Health Science, which some authors define as Public Health 3.0 1 .Since the 1990s such term has been used in the university setting and by policymakers signaling inflows of new theories and methods to traditional public health.In Valles 2 (1) words, "it synthesizes the expertise of scientists and non-scientists to understand the full range of causes" (too much ambitious?)"[...] of health and illness, seeking to improve health through collaboration of diverse sectors of society".In the author's view, though an emerging field, no previous philosophy book made such an effort of analyzing the rise of population health 2 .
Regarding its origins, it goes back to the gradual recognition of health as a social phenomenon.With regards its scope, it argues for a pluralistic understanding of health in different social and historical contingent realities.The author devises health equity interventions through democratic decision-making processes and highlights the need to communicate with the public about what Population Health Science means as a form to engage them as active social actors.It converges herein with the ideas of Mario Testa, an Argentinian scholar well-studied by Lígia Giovanella (maybe not known by the author, as she not cited in this book) 3 .
Critically appraising the author's goal of intellectually supporting population health with his book, it resembles Georges Canguilhem in the 1960s with regards to his proposal of analyzing Medicine, cited herein: I think that Population Health has a history and a life trajectory of its own, depending mainly on the Humanity (audacious Humanity) it represents to consolidate its proposals.Pragmatically speaking, as previously shown in human history, we can still trace the influence of the French Revolution in Latin America's Independence Movements from European colonialism; English Industrial Revolution rooted to the eighteenth century according Hobsbawn 5 is still a wave that explains Industry 4.0; the Brazilian Sanitary Reform which was initiated in the 1970s is still moving forth and through its initial (still residuals) structural resistance.
After all, what "Population Health Science" is? "A conceptual approach to understanding the drivers of health and consequently the strategies most useful to improve health" 2(4). Or: A research program that confronts the structural forces that place individuals at risk, creates distributions of health and disease unequally across socially defined groups, and focuses on embedding biological pathways within social interactions that develop across the life course and across generations 2 (4) .
The author mentions two other movements such as Social Medicine and the People Health Movement, and states that they differ from this new field.They share the commonality of being reactions against the biomedical model of health which was hegemonic in the twentieth century.Later, the author describes something that helps to differentiate Social Medicine and Population Health, when he states that physicians aren't the automatic rightful leaders in addressing health matters.This is true, and physicians need to contextualize and perhaps overcome Rudolf Virchow's famous statement: "Medicine is a social science, and politics nothing but medicine at larger scale".
Valles 2(12) argues that the history of Population Health Science theory is best understood as the synthesis of four different inflows that converged to the public health theory in the twentieth century: (1) the first insight was that health is social, metaphysically speaking, in accordance with WHO's definition back to the 1940s "as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity" (2) the second insight was that health is empirically social (one should refer here to the Whitehall Study conclusions 6 ) and a main goal of public health should be scrutinize health social determinants, (3) third, health is ethically inseparable from social empowerment, a concept rooted in the nineteenth century social reform and advanced onto the twentieth century by Latin America's scholars intellectual works, (4) and finally, methodologies of health research and health promotion must contemplate health as a social phenomenon too; a prototypical example of the latter is communitybased participatory research which sees subjects as respected "research partners and bearers of essential knowledge" 2(31) for a change.
When writing on the social determinants of disease, and explaining about causes of individual cases of disease versus causes of between-population disease disparities, the author advocates orienting philosophy of the population health to Aaron Antonovsky's model of salutogenesis rather than pathogenesis.Valles coherently advices that social life of individuals should be regarded as foreground, not background, to understand disease and health in their life trajectory course.
Explaining the concept of fundamental causes of health, he points out that even not understanding (as Epidemiology intends to do) the complexity of causation operating in different health settings, it is reasonable to confront poverty or racism, on the other hand to promote education, as modes of just cutting the knot of health idiosyncrasies in that setting instead of trying to untangle it.Simpler but not faster, as health effects of such interventions tend to be noticed generations ahead.As taught by the author, since fundamental causes "operate as flexible buffers against a wide array of harms, they lack onecause-one-effect relationships, but their effects are reliable in their directionality" 2(108) .I should say, they give robustness to their effects and could advance the field of public health, here understood as Population Health (in Brazil, one should name it 'Collective Health').Instead of trying to investigate 'causes of cases', as we are prone to do in traditional epidemiology, population health defends investigating diverse 'causes of incidence' between populations.It seems to me thta is quite similar as trying to decipher what really goes on in ecological studies (eternal enigma?).Contrasting with the main and humble scope of traditional public health trying to describe 'what' is occurring in a specific health setting, we ought to analyze 'why' is it occurring in that contingent socio-historic context.
More than a form of trying to understand the world in its complexities with regards the health field, the Population Health (in Valles' view) or Brazilian Collective Health on my own perspective, has the humble ambition (is it possible?)and primary goal of transforming the world through the population engagement.The socioeconomical and cultural dimensions of human life put ahead, towards their legitimate place, not staying on the background, health inequalities may gain the proper perspective.Trying to sensitize social actors is something that qualitative research is gradually doing, something that Latin American scholars and practitioners are already struggling with for decades (back to the 1970s in Brazil).That wave should not end.As a paraphrase of Canguilhem's 4(7) previous quote, I dare to say that: "Si la Santé Collective doit être rénovée, c'est aux collectivités de le faire à leurs risques et à leur honneur".