Wolff, Robert Paul, The Autonomy of Reason. New York: Harper, 1973.

Excerpt:

“Groundwork of the Metaphysics of Morals is probably the most difficult short work in modern philosophical literature. Despite its great popularity—it is, after the Critique of Pure Reason, the most widely read and commented upon of Kant’s writings—scholars and philosophers have arrived at no common agreement about what it seeks to prove, what arguments it employs, or whether it is successful.  Even the careful reader is baffled by the complex chains of reasoning compressed into brief paragraphs and then beguiled by  a series of surprisingly concrete examples which prove sadly misleading as clues to the more abstract doctrines surrounding them.

Some of the obscurity of the text is caused by the unfamiliarity of Kant’s terminology, particularly in the area of psychology. Considerable confusion, too, is created by Kant’s penchant for mixing up different and opposed methods of exposition, so that at one time he will merely explore the connections among concepts hypothetically, at another attempt a formal proof from premises to conclusions. But when the confusions have been sorted out, and we have, in W.S.  Gilbert’s words, “got up all the germs of the transcendental terms,” we are still left with the root difficulty of the work: Kant’s own unclarity,  and inconsistency about the doctrines he wishes to expound. It is simply not possible to fit all of the principal doctrines of the groundwork into a single coherent chain of arguments, despite the most generous allowance for lapses of clarity, momentary vagary, or even inconsistency.”

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