UC San Diego

My dissertation represents the first sustained philosophical treatment of the science of molecular motor proteins—proteins that transform the chemical energy stored in ATP into mechanical motion. The analysis proceeds from a broadly mechanistic philosophical perspective, albeit one that has witnessed two recent developments. First, philosophers both within and in the orbit of mechanist philosophy of science have recently turned philosophical attention to how scientists characterize phenomena, as opposed to explain them, the latter being New Mechanism’s traditional focus. The first section, Characterization (Chapters 1 & 2), contributes to this still nascent philosophical discussion. I draw case studies from the history of cell biological research on motor proteins to analyze key experimental practices by which scientists succeeded in characterizing (as opposed to explaining) the activity of molecule motor proteins both quantitatively (Chapter 1) and qualitatively (Chapter 2). Second, the perspective on biological mechanisms that I adopt is a “revisionist” one initially formulated by my supervisor, William Bechtel, and his former graduate student Jason Winning that construes biological mechanisms as sets of constraints on the flow of free energy. Each chapter of the second section, Explanation (Chapters 3, 4, &5) extends this philosophical view in connection with analyses of the explanatory practices of molecular motors researchers.