Abstract

This dissertation explores the fundamental role of spatial representation in constituting thought. The thesis of this dissertation is that spatial representation is a fundamental constituent of thought in two ways. First, reference is a metaphorical extension of grasping material objects located in physical space. Second, predication is the relative placement of representations of these referents in a high-dimensional neural activation space. Hence, spatial representation, albeit in two different senses, is fundamental to both reference and predication, which are themselves the fundamental constituents of thought. In other words, "spatial representation" actually plays two fundamental roles in thought: the representation of objects as located in physical space allows us to refer to them, and the representation of objects in activation space allows us to conceptualize them. ;After a brief introduction in Chapter 1, the first part of this dissertation situates the problem of spatial representation in philosophical context, both synchronically and diachronically . The second part considers in detail Strawson's "Kantian" arguments for the fundamental importance of spatial representation. It concludes that, although Strawson does not carefully distinguish the importance of physical space for reference from the importance of activation space for predication, his arguments ultimately pertain to both. The final part of this dissertation presents an argument for the fundamental importance of neural activation space in categorizing stimuli and defends this "state-space semantics" against the charge that it cannot support any notion of identity of content. In addition to a method for comparing the similarity of representations across neural networks, the chapter contains the results of empirical studies with artificial neural networks demonstrating that internal representations are often remarkably similar in "speakers" of the same artificial language, despite differences in inputs and architectures. The conclusion contains a summary of the dissertation and suggestions for future research