Cultural Divergence: Elie Metchnikoff's Bacillus bulgaricus Therapy and His Underlying Concept of Health

All the world over and at all times there have been practical men, absorbed in “irreducible and stubborn facts”: all the world over and at all times there have been men of philosophical temperament who have been absorbed in the weaving of general principles.

Alfred North Whitehead ¹

To what extent does philosophy influence medicine? The division between practical scientists and pondering philosophers is herein examined by focusing upon the origin and fate of Elie Metchnikoff’s Bacillus bulgaricus therapy in the earliest decades of this century. Metchnikoff helped drive the rise of the yogurt industry through his proposal to transform the toxic flora of the large intestine into a host-friendly colony of B. bulgaricus. This therapy, at first intended as a preventive against the infirmities of old age, was presented in the context of the famous scientist’s conception of the living organism as intrinsically disharmonious—a conception diametrically opposed in orientation to the predominating late-nineteenth-century conceptions of harmony and balance. However, by the time Metchnikoff’s therapy was assimilated by the English-speaking world, its philosophical origins had been forgotten and its use confined to the alleviation of specific intestinal disorders.

In this article I will first trace the course of Metchnikoff’s therapy through three stages: its incipience, the rejection of its underlying theoretical foundation in England in the first decade of the century, and the subsequent development of the therapy in the United States from the 1920s to the 1930s. Then, having explored the vagaries of Metchnikoff’s famous therapy, I will trace the lesser-known fate of its theoretical foundations—from their initial rejection, to their ultimate infiltration into American and British conceptions of health. My intent is to demonstrate that the differential rates of diffusion of Metchnikoff’s novel therapy and theory into such cultures actually depended not only upon the therapy’s potential efficacy, but also upon the differences between the underlying philosophy of the theory and the philosophical expectations of its recipients.

Metchnikoff’s Formulation of the Theory and Therapy

Elie Metchnikoff was born in the Kharkov province of Russia in 1845. He was a volatile, neurotic, yet brilliant child—traits that would persist throughout his scientific career. By the 1860s, he had completed his formal studies in embryology. The antiprogressivism characterizing his view of embryology, as this article will show, led him to an understanding of the relationship between ontogeny and phylogeny that differed in important ways from the relationship propounded by Ernst Haeckel’s recapitulationist program. ² Metchnikoff most famously extended this antiprogressivism to his explanation of the process of inflammation: in 1883, through his experimental placing of thorns in starfish larvae, he first described the “phagocyte” as the amoeboid mediator of cellular immunity. Moving to the Pasteur Institute in 1888, Metchnikoff vociferously defended the importance of the role played by cellular immunity until his death in 1916, earning himself the Nobel Prize in 1908. But it is to his more popular exploits that this article now turns.

Metchnikoff’s original desire to transform the human intestinal flora was presented to the public in the first decade of this century as the result of a complex chain of ideas stemming from a unique underlying conception of health and pathology. ³ Most late-nineteenth-century conceptions of the individual postulated health as a condition of given harmony, and pathology as a temporary deviation from such a healthy underlying state. ⁴ Metchnikoff, however, as Alfred Tauber and Leon Chernyak have emphasized, reversed this conception: according to him, “the organism was intrinsically disharmonious and its biology was based on the endeavor of integrating the disharmonious elements by active processes.” ⁵ This reversal derived from a reinterpretation of ontogeny and phylogeny in large part stemming from Metchnikoff’s own particular reading of Darwinism. ⁶ At the level of ontogeny, he proposed a type of intraorganismic Darwinism, explaining that “embryological development proceeds with cell lineages that are potentially in competition. The organism cannot be viewed as growing as a harmonious whole. . . .” ⁷ The growing organism required active “harmonizers,” and...