Medicine from Art to Science: The Role of Complexity and Evolution (review)

Giovanni Felice Azzone. Medicine from Art to Science: The Role of Complexity and Evolution. IVSLA [Veneto Institute of Sciences, Letters & Arts] series, vol. 1. Amsterdam: IOS Press, 1998. viii + 197 pp. $60.00.

In this ambitious book Giovanni Felice Azzone discusses the transformation of Western medicine from its Hippocratic-Galenic roots into what he argues is now an authentic natural science. The book is less concerned with the art of medical practice than with medical epistemology. The conceptual or epistemological transformation was the change from a symptomatic classification of disease to a classification based on histopathological lesions and pathophysiological mechanisms. The main architects of this transformation were Giovanni Battista Morgagni, who began to classify diseases according to pathological anatomy; the nineteenth-century Paris clinical school, whose members correlated clinical manifestations of disease with their underlying pathologies; and Claude Bernard, who viewed disease as the consequence of alterations in physiological processes. In the author's view, this change from a descriptive classification of disease to one based on determinism converted medicine from a natural history, or "art," to a "science."

Bernard not only helped to establish physiology as the scientific basis of medicine but also established it as an autonomous discipline, distinct from physics, chemistry, and zoology. One consequence of this disciplinary autonomy was the isolation of physiology--and medicine--from evolutionary biology and ecology. Physiology remained focused on individual organisms and the milieu intérieur, and neglected variation, chance, and the interactions of organisms with their external environments. The recent recognition of the importance of evolutionary processes in medicine has wrought new changes in the nature of medical science. Azzone tries hard to integrate an evolutionary perspective with medicine's nineteenth-century deterministic roots. This is an important and difficult challenge; while he has not, in my view, been completely successful, he should be commended for trying.

The evolutionary processes of variation and selection have many implications for medicine. Azzone shows how the clonal-selection theory of the immune response and the somatic-mutation theory of cancer necessitate revisions in our concepts of disease. Because the immune response depends upon random events of mutation and genetic recombination, the outcome of an immune response to a pathogen is indeterminate. Likewise, even though cancer may result from somatic mutations, no specific mutations are either necessary or sufficient for the development of cancer. Variation within populations is another source of variation in disease processes. Moreover, since populations or species change over time, their diseases must also change over time. I especially liked Azzone's discussion of eugenics, in which he points out that genes by themselves are not diseased or pathological, even though their effects in certain combinations, in individuals in certain environments, may lead to disease. Genetic diversity is not only our evolutionary heritage but our hope for an evolutionary future.

Given Azzone's recognition of the importance of developmental processes, I was disappointed that he did not pay more attention to the roles of environment and culture in disease. Syphilis is a different disease today from what it was in the sixteenth century--not only because it is now defined as infection by T. pallidum rather than as "great pox," and because the interaction of T. pallidum with humans has led to selection of both the parasite and its host, but also because humans now encounter spirochetes in a culture that differs markedly in nutrition, hygiene, and beliefs from that of the sixteenth century.

The book is a collection of mostly unpublished essays on the history and philosophy of medicine. Inevitably, such a collection contains a considerable amount of redundancy. Because the book lacks an index, it is difficult for readers to find common themes in different chapters. The reference section is woefully incomplete: many references that are cited in the text are not listed in the references. There are more spelling errors and grammatical infelicities than...