Chapter XVI: Appendix: A

A SYNOPTICAL SUMMARY OF THE SCHEME OF THE ARGUMENT TO PROVE THE DIVERSITY IN KIND[166] OF THE REASON AND THE UNDERSTANDING. SEE P. 143.

The Position to be proved is the _difference in kind_ of the Understanding from the Reason.

The Axiom, on which the Proof rests, is: Subjects, which require essentially different General Definitions, differ _in kind_ and not merely _in degree_. For difference _in degree_ forms the ground of _specific_ definitions, but not of _generic_ or general.

Now Reason is considered either in relation to the Will and Moral Being, when it is termed the[167] Practical Reason = A: or relatively, to the intellective and Sciential Faculties, when it is termed Theoretic or Speculative Reason = _a_. In order therefore to be compared with the Reason; the Understanding must in like manner be distinguished into the Understanding as a Principle of _Action_, in which relation I call it the Adaptive Power, or the faculty of selecting and adapting Means and Medial of proximate ends = B: and the Understanding, as a mode and faculty of thought, when it is called Reflection = _b_. Accordingly, I give the General Definitions of these four: that is, I describe each severally by its _essential characters_: and I find, that the definition of A differs _toto genere_ from that of B, and the definition of _a_ from that of _b_.

Now subjects that require essentially different definitions do themselves differ in kind. But Understanding and Reason require essentially different definitions. Therefore Understanding and Reason differ in kind.

[166] This summary did not appear in the first edition.--ED.

[167] N. B. The Practical Reason alone _is_ Reason in the full and substantive sense. It is reason in its own sphere of _perfect freedom_; as the source of _IDEAS_, which Ideas, in their conversion to the responsible Will, become Ultimate Ends. On the other hand, Theoretic Reason, as the ground of the Universal and Absolute in all logical _conclusion_ is rather the _Light_ of Reason in the _Understanding_, and known to be such by its contrast with the contingency and particularity which characterize all the proper and indigenous growths of the Understanding.