Alexandre Francq

Philosophers of science frequently appeal to “complexity” to justify scientific pluralism—the view that some domains require multiple, perhaps non-integrable, models or explanations. This article argues that such appeals often rely on an unexamined metaphysical interpretation of complexity, according to which complexity is an intrinsic property of the world capable of grounding normative methodological prescriptions. I show that this interpretation is both unjustified and unproductive. Through critical analyses of Mitchell’s integrative pluralism, Waters’s “no-structure” argument, and Longino’s account of human behavior, I show that their supposed metaphysical claims about complex systems are in fact epistemic claims in disguise. Once this is acknowledged, metaphysical complexity cannot sustain the strong methodological conclusions pluralists often draw from it. In place of metaphysical foundations, I propose a pragmatist account of complexity. Drawing on Wittgenstein’s notion of family resemblance and Neurath’s concept of Ballungen, I argue that complexity functions as a flexible, non-essentialist cluster concept whose meaning is stabilized through overlapping similarities and paradigm cases, rather than necessary and sufficient conditions. This view preserves the heuristic and organizational role of complexity in scientific inquiry while avoiding unwarranted ontological commitments. Complexity remains philosophically and scientifically useful not because it designates a natural kind, but because it coordinates diverse investigative strategies and supports context-sensitive forms of pluralism. A genuinely pragmatist pluralism, I conclude, requires abandoning the search for metaphysical grounding in favor of a reflexive, non-foundationalist stance.

Philosophical accounts of disagreement typically distinguish substantive disputes, which concern facts or concepts, from merely verbal disputes, which arise from divergent uses of language. The latter are often treated as inconsequential, on the grounds that they can be dissolved through clarification of terminology. This article challenges that assumption through a case study in cancer biology concerning tumor temporary growth arrest (TGA). Drawing on a historical and conceptual analysis of the literature, I reconstruct the emergence of competing uses of the terms “dormancy” and “quiescence,” and argue that the resulting disagreement can be understood as a genuinely verbal dispute in the standard sense: once the relevant terms are regimented, no disagreement over the underlying biological phenomena remains. I then show that, despite its verbal character, this dispute is consequential for scientific practice. Terminological disagreement affects communication within and across disciplines, complicates the coordination of research, and shapes the transmission of knowledge to students, clinicians, and the public. Moreover, it reflects underlying normative commitments, including tensions between disciplinary continuity and standardization across fields. The case thus illustrates how scientific terminology is not a neutral vehicle for describing facts, but a value-laden component of inquiry. The paper concludes that the common inference from the verbal character of a dispute to its inconsequentiality should be rejected, at least in the context of the life sciences. More generally, it argues that adequate accounts of disagreement must take into account the practical and normative roles of language in scientific practice.

Kuhn (1962) proposed an evolutionary model to explain how scientific knowledge is built, based on the concept of paradigm. Even though Kuhn’s model is general, it has been applied to only a few topics in evolutionary biology, almost exclusively to broad-based paradigms. We analyze here, through the lens of Kuhn’s theory, a small-scale paradigm change that occurred with the resolution of the controversy about the mating system of a Mediterranean shrub Phillyrea angustifolia (Oleaceae). We first summarize the different steps of the paradigm change and replace them in the more general context of sex ratio theory. Second, we show how the different steps of the paradigm change can be interpreted by Kuhnian concepts and tools. Finally, we discuss the actual and future status of the new paradigm.