Plasticity and language: an example of the Baldwin effect? Kevin Zollman Department of Philosophy Baker Hall 135 Carnegie Mellon University Pittsburgh, PA 15213-3890 Rory Smead * Department of Logic and Philosophy 3151 Social Science Plaza A University of California Irvine, CA 92697 October 20, 2009 Abstract In recent years, many scholars have suggested that the Baldwin effect may play an important role in the evolution of language. How- ever, the Baldwin effect is a multifaceted and controversial process and the assessment of its connection with language is difficult without a formal model. This paper provides a first step in this direction. We examine a game-theoretic model of the interaction between plastic- ity (represented by Herrnstein reinforcement learning) and evolution in the context of a simple language game. Additionally, we describe three distinct aspects of the Baldwin effect: the Simpson-Baldwin ef- fect, the Baldwin expediting effect and the Baldwin optimizing effect. We find that a simple model of the evolution of language lends the- oretical plausibility to the existence of the Simpson-Baldwin and the Baldwin optimizing effects in this arena, but not the Baldwin expe- diting effect. Humans and many other animals are extremely adaptive. Individuals are capable of changing their behavior in response to a wide variety of different * The authors would like to thank Brian Skyrms, Bill Harms, Kyle Stanford, Brad Armendt, and Santiago Amaya for helpful suggestions. 1