Reason and Action

According to Kant, the imperatival form of his principle of Pure Practical Reason expresses the discrepancy between a hypothetical perfectly rational entity and an imperfectly so one.  Hence, the "Act" of the formula is extrinsic to the concept of perfectly rational performance, therefore, leaving unexplained the motivation, and, thus, the self-motivation of that rational ideal.  In contrast, Spinoza can ascribe activation to the attribute of Extension, a structural component of a rational entity that has no obvious analogue in Kant's system, leaving Action as an empirical concept in it.