A Shot in the Arm for Philosophy of Biology: How to Treat Infectious Diseases

This article analyzes infectious diseases (IDs) within a philosophy of biology framework to locate factors that play a role in the development of a successful account of IDs. One way to handle the analysis of kinds in biology is through a traditional essentialist approach whereby biological entities are construed as natural kinds with essences. Approaching IDs in this way is unworkable, however, because it is difficult to find essences that occur in all and only IDs. Rather than engaging IDs from this perspective, my analysis of the nature of IDs more appropriately falls under the rubric of philosophy of biology whereby I treat particular IDs as products of evolution with a unique relationship to the biological hierarchy. This approach is what I refer to as an evolutionary perspective of IDs because it emphasizes that the constituent mechanisms and processes of ID are sensitive to evolutionary pressures. Such an approach is useful because it allows us to sidestep difficulties pervasive traditional kind essentialist accounts of ID. To begin, I analyze two contemporary methods for analyzing kinds in biology-Richard Boyd's Homeostatic Property Cluster (HPC) kind approach and Paul Griffiths' treatment of kinds with historical essences. I discuss both approaches and identify the limitations of each that prevent a successful account of IDs. I then analyze how elements of each account can be revised into a successful philosophy of biology approach to IDs. The article is concluded with a brief discussion of the benefit of incorporating an evolutionary perspective into the analysis of IDs and outlines future projects that result from approaching IDs from an evolutionary perspective.