Abstract
For most commentators, the universality of Descartes’s method goes hand in hand with the uniformity with which it must be applied to any problem in any science. I will henceforth refer to this as the Uniformity Thesis. Finding themselves unable to identify such a uniformly applied method in any of Descartes’s extant treatises, many readers of Descartes have been led to conclude that Descartes’s method played little or no role in Cartesian science. My principle argument will be that Descartes did not, in fact, accept the Uniformity Thesis, and that the relevant textual evidence strongly suggests that he denied it. For Descartes, the method is universal, and can be employed to discover scientia, not because it can or ought to be uniformly applied to any problem in any science, but rather because practice in the method habituates the human ingenium to be sensitive to diff erent kinds of problem, such that the procedure for constructing and resolving a problem can, within definable limits, vary from application to application