A similarity space is a hyperspace in which the dimensions represent various dimensions on which objects may differ. The similarity space theory of concepts is the thesis that concepts are regions of similarity spaces that are somehow realized in the brain. Proponents of such a theory of concepts include Paul Churchland and Peter Gärdenfors. This paper argues that the similarity space theory of concepts is mistaken because regions of similarity spaces cannot serve as the components of judgments. It emerges that (...) although similarity spaces cannot model concepts, they may model a kind of nonconceptual representation. (shrink)

Just how far can externalism go? In this exciting new book Ruth Millikan explores a radically externalist treatment of empirical concepts (Millikan 2000). For the last thirty years philosophy of mind’s ties to meaning internalism have been loosened. The theory of content has swung uncomfortably on its moorings in a fickle current, straining against opposing ties to mind and world. In this book Millikan casts conceptual content adrift from the thinker: what determines the content of a concept is not cognitively (...) accessible. She has only the stanchion of the world to hold her theory fast. She hopes that the tide will turn, and the theory of meaning will come stably to rest downstream of this anchor. This book is a bold exploration of how that might be achieved. (shrink)