This paper addresses theoretical challenges, still relevant today, that arose in the first decades of the twentieth century related to the concept of the organism. During this period, new insights into the plasticity and robustness of organisms as well as their complex interactions fueled calls, especially in the UK and in the German-speaking world, for grounding biological theory on the concept of the organism. This new organism-centered biology understood organisms as the most important explanatory and methodological unit in biological investigations. (...) At least three theoretical strands can be distinguished in this movement: Organicism, dialectical materialism, and holistic biology. This paper shows that a major challenge of OCB was to describe the individual organism as a causally autonomous and discrete unit with consistent boundaries and, at the same time, as inextricably interwoven with its environment. In other words, OCB had to conciliate individualistic with anti-individualistic perspectives. This challenge was addressed by developing a concept of life that included functionalist and metabolic elements, as well as biochemical and physical ones. It allowed for specifying organisms as life forms that actively delimit themselves from the environment. Finally, this paper shows that the recent return to the concept of the organism, especially in the so-called “Extended Evolutionary Synthesis,” is challenged by similar anti-individualistic tendencies. However, in contrast to its early-twentieth-century forerunner, today’s organism-centered approaches have not yet offered a solution to this problem. (shrink)

In the 1930s, two concepts excited the European biological community: the organizer phenomenon and organicism. This essay examines the history of and connection between these two phenomena in order to address the conventional ‘rise-and-fall’ narrative that historians have assigned to each. Scholars promoted the ‘rise-and-fall’ narrative in connection with a broader account of the devitalizing of biology through the twentieth century. I argue that while limited evidence exists for the ‘fall of the organizer concept’ by the 1950s, the organicism that (...) often motivated the organizer work had no concomitant fall – even during the mid-century heyday of molecular biology. My argument is based on an examination of shifting social networks of life scientists from the 1920s to the 1970s, many of whom attended or corresponded with members of the Cambridge Theoretical Biology Club . I conclude that the status and cohesion of these social networks at the micro scale was at least as important as macro-scale conceptual factors in determining the relative persuasiveness of organicist philosophy. (shrink)