The Idealization of Causation in Mechanistic Explanation∗

Causal relations among components and activities are intentionally misrepresented in mechanistic explanations found routinely across the life sciences. Since several mechanists explicitly advocate accurately representing factors that make a difference to the outcome, these idealizations conflict with the stated rationale for mechanistic explanation. We argue that these idealizations signal an overlooked feature of reasoning in molecular and cell biology—mechanistic explanations do not occur in isolation—and suggest that explanatory practices within the mechanistic tradition share commonalities with model-based approaches prevalent in population biology. 1 More Thoughts About Mechanisms The concepts of mechanism and mechanistic explanation have recently received much attention in philosophy of science. This increased scrutiny has had a polarizing effect. On the one hand, supporters suggest that thinking about mechanisms sheds light on many central issues, such as causation, explanation, reduction, and emergence. For instance, it has been claimed that the “openendedness” of mechanistic explanations, which are not limited to linguistic representations and may involve diagrams or simulations, constitutes a substantial advantage over deductive-nomological inferences (Bechtel and Abrahamsen 2005). On the other hand, critics have argued that these concepts are insufficiently characterized or suffer from distinctive problems. For example, systems ∗Acknowledgements: Both authors contributed equally to this work. Earlier versions were presented at the 2014 Philosophy of Biology at Madison workshop and the 2014 PSA Biennial Meeting in Chicago. We are grateful to both audiences and to an anonymous reviewer for helpful feedback. †Department of Philosophy, Minnesota Center for Philosophy of Science, University of Minnesota, 831 Heller Hall, 271 19th Ave S, Minneapolis, MN, 55455. Email: [email protected] ‡Department of Philosophy, University of Denver, 264 Sturm Hall, 2000 E. Asbury Ave, Denver, CO, 80208. Email: [email protected]