396 Kant: A BiographyThe two Metaphysical Foundations belong together, and they were pub¬
lished again as one book in 1797, namely as The Metaphysics of Morals. A
second edition of the two parts appeared as early as 1798. Kant added to
this edition an Appendix, in which he answered objections from a review
in the Göttingische gelehrte Anzeigen of 1797. This book fulfills Kant's prom¬
ise of presenting "the whole system" of human duties, plans for which go
back at least to 1767. It had taken Kant much longer to unearth all of its
critical presuppositions than he had anticipated. Finally, at the age of
seventy-four, in the process of tying things up, he gave to the public this
work, which was more comprehensive than the one planned, offering not
only an account of all ethical duties but also views on the philosophy of
law. Yet, compared to the Groundwork and the second Critique, the Meta¬
physics of Morals is disappointing. It exhibits none of the revolutionary
vigor and novelty of the two earlier works. Indeed, it reads just like the
compilation of old lecture notes that it is. Given Kant's difficulties and
weakness, it is not surprising that much remains cryptic and that some of
the text is corrupt.^55 Kant simply did not have the energy to satisfactorily
pull together all the different strands of his arguments, let alone polish the
work. Indeed, he even had difficulties with supervising the printing of the
book. This, of course, does not mean that the work is without interest or
even unimportant. The ideas Kant presented go back to his most produc¬
tive years. It is important for understanding not only his moral philosophy
but also his political thinking. It is indeed a veritable tour de force. Yet, if
the work "make[s] demands upon its readers that seem excessive even by
his standards," its creation made demands upon Kant that were even more
excessive.^56
The argument of the work is based on a distinction between duties of
justice and duties of virtue, or between juridical and ethical duties. Kant
claims that the laws freely adopted by rational agents like us are based on
these two types of duties. Roughly speaking, The Metaphysical Foundations
of the Doctrine of Right deals with the former, The Metaphysical Founda¬
tions of the Doctrine of Virtue deals with the latter.^57 Both have to do with
legislation, but of two types: political and personal. Juridical legislation
deals with what is required or permitted in an external sense, while ethical
legislation is, for Kant, "inner legislation." Since both kinds of legislation
give rise to laws that must be able to be freely adopted by rational beings,
there are for Kant two kinds of freedom as well. They are outer freedom and
inner freedom. Correspondingly, juridical laws are laws of outer freedom,
and ethical laws are laws of inner freedom. The ethical laws are ultimately