Populations of Neurons and Rocks? Against a Generalization of the Selected Effects Theory of Functions

Jakob Roloff

Justus Liebig University Gießen

Ruth Millikan’s (1984) selected effects theory of functions states that having a function does not consist in having a certain disposition, but in the fact that the ancestors of the trait were selected for because they showed certain effects. As the function is an effect a thing’s ancestors showed, only things that are reproductions in some sense can have functions. This central claim of Millikan’s theory of selected effects functions has been put under pressure lately by Justin Garson (2019). Garson argues that not only processes of differential reproduction but also processes of differential persistence can lead to new functions. In some cases of differential persistence, a certain effect a thing showed in the past can explain why the same thing still exists. As such persistence functions thus have the same explanatory power as traditional selected effects functions, selected effects theorists should adopt Garson’s generalized theory and include persistence function in their framework.
In my presentation, I will examine whether proponents of Millikan’s theory should accept Garson’s argument and adopt his generalized theory. I will try to show that the proponents of the generalized theory have yet to provide a working notion of populations that manages to avoid a liberality problem. Further, I will argue that persistence functions are at best a marginal case of functions as they differ significantly from traditional selected effects functions acquired by differential reproduction. They cannot explain the proliferation of a certain trait within a population, but only explain how a whole individual managed to persist longer than other individuals. Since they are two different phenomena, it is best not to mix them together.

References
Garson, Justin (2019). What Biological Functions Are and Why They Matter. Cambridge University Press.
Millikan, Ruth G. (1984). Language, Thought, and Other Biological Categories: New Foundations for Realism. MIT Press.

Chair: Cristina Somcutean

Time: September 6th, 18:50-19:20

Location: SR 1.007