Abstract

This paper poses a dilemma for applying the category of substance given Kant's different conceptions of substance in the Critique of Pure Reason. Briefly stated, if the category of substance applies to an omnipresent and sempiternal substance, then although this would ensure that all experiences of empirical objects take place in a common spatiotemporal framework, one could not individuate these empirical objects and experience their alterations. If the category of substance applies to ordinary empirical objects, however, then although one could individuate these substances and experience their alterations, the category would not pick out a common spatiotemporal framework for these experiences. I will argue that this dilemma can be overcome by examining the development of Kant's conception of substance in his final work, the Opus postumum.