Kant's noncognitive argument based on practical reason claims that moral considerations alone suffice to justify the idea of personal immortality as a postulate. Some recent objections are considered here that have charged him with overstepping his own distinction between phenomenon and noumenon. After examining the arguments, Kant is exonerated of having violated his own principles. More troubling, however, is the peculiarity involved in postulating an infinite progression toward a goal whose attainment, by hypothesis, would undermine the very foundations of morality (which for Kant always requires the agonistic condition of struggling to improve one's lower nature). It is argued that this paradox necessitates a reexamination of some tacit cultural presuppositions underlying Kant's conception of the soul. Finally, an examination is made of the thought of Kitarō Nishida, whose Zen Buddhist–inspired dialectic of the basho (logical "place") provides an alternative perspective from which to reconsider the postulate of immortality. Nishida, like Kant, rigorously maintains the phenomenonnoumenon distinction, yet his examination of ethics leads him to postulate an eventual sublation of the "soul" principle. It is concluded that Kant's postulate of immortality, while plausible enough on its own terms, is limited by a Western cultural bias and therefore fails in the end to be compelling.