Gary Hatfield examines theories of spatial perception from the seventeenth to the nineteenth century and provides a detailed analysis of the works of Kant and Helmholtz, who adopted opposing stances on whether central questions about spatial perception were fully amenable to natural-scientific treatment. At stake were the proper understanding of the relationships among sensation, perception, and experience, and the proper methodological framework for investigating the mental activities of judgment, understanding, and reason issues which remain at the core of philosophical psychology (...) and cognitive science. (shrink)

This paper deals with an attempt of the mathematician Riemann to develop an outstandingly broad view of the philosophy of nature encompassing basic phenomena of both the material and the mental world. Riemann's draft is traced in its main aspects, and is accompanied by a comparison with certain chapters in the philosophical writings of Herbart that were particularly relevant to Riemann's conception of mathematics and science on the whole. This applies, in particluar, to the epistemological background and to Herbart's theory (...) of the Self. (shrink)