expressed thus: Act as if the maxim of thy action were to become by
thy will a universal law of nature.

We will now enumerate a few duties, adopting the usual division of
them into duties to ourselves and ourselves and to others, and into
perfect and imperfect duties. *



* It must be noted here that I reserve the division of duties for a
future metaphysic of morals; so that I give it here only as an
arbitrary one (in order to arrange my examples). For the rest, I
understand by a perfect duty one that admits no exception in favour of
inclination and then I have not merely external but also internal
perfect duties. This is contrary to the use of the word adopted in the
schools; but I do not intend to justify there, as it is all one for my
purpose whether it is admitted or not.



1. A man reduced to despair by a series of misfortunes feels wearied
of life, but is still so far in possession of his reason that he can
ask himself whether it would not be contrary to his duty to himself to
take his own life. Now he inquires whether the maxim of his action
could become a universal law of nature. His maxim is: "From
self-love I adopt it as a principle to shorten my life when its longer
duration is likely to bring more evil than satisfaction." It is
asked then simply whether this principle founded on self-love can
become a universal law of nature. Now we see at once that a system
of nature of which it should be a law to destroy life by means of