From Structure to Dynamics: Making Sense of Conceptual Change in Protein Science

Guest speaker: Jacob Neal, Postdoctoral Associate at the Rotman Institute of Philosophy at Western University

Proteins do most of the cellular work in biology: enzymes convert our food into energy, hemoglobin delivers oxygen to our cells, and antibodies help us respond to infections. Understanding protein function is therefore a major goal of the molecular life sciences. Since the mid-twentieth century, scientists have conceptualized proteins in two very different ways. The structural concept of the protein emerged during the heyday of molecular biology. According to this concept, each protein has a fixed 3D structure, and structure alone is sufficient to determine the protein’s function. The dynamic concept of the protein arose out of a theoretical critique of the structural concept. According to this concept, a protein is a dynamic molecule, undergoing constant structural fluctuations. Scientists adopting this concept maintained that dynamical properties of these fluctuations played an additional key role in determining protein function. In this talk, I analyze the complex epistemic relationships that obtain between these two conflicting scientific accounts. I offer a novel perspective on such conflicts by distinguishing the conceptual change involved from the associated change in scientific representations. I argue that rational conceptual replacement, rather than a Kuhnian revolution, is the correct way to characterize this development. But conceptual replacement does not entail the replacement of older representations. This distinction enables my account to explain both the drastic conceptual change in protein science as well as the retention of structural representations of proteins. This case also enables me to draw some more general conclusions about rational conceptual change in science.

Friday, February 25, 2022
4 – 5:30 p.m. MST
LSC 372-374

Questions? Contact jeff.kasser@colostate.edu