Kant’s deduction of the categorical imperative is the answer to the following

question: “How is a categorical imperative possible?” The answer

is given in subsection 4 (Sec. 4) of chapter three of the Groundwork.

It is impossible to understand this answer, and hence impossible

to understand Kant’s deduction of the moral law, without taking into

account the overall context of Groundwork III (GMS III). However,

here I can only sketch the overall structure of GMS III, and therefore

only present a sketch of what I call Kant’s thesis of analyticity.1 This

thesis is developed in Sec. 1 of GMS III; however, it appears time and

again in GMS III, and it deserves special attention (part 1). Part 2,

then, offers a close reading and analysis of Kant’s deduction.