Abstract

(Ak 10:74).[1] During the so-called ‘silent decade’ of the 1770s, when Kant was working on the Critique of Pure Reason, he promised repeatedly not only that he would soon finish that work but also that he would soon publish a “metaphysics of morals” (Ak 10:97, 132, 144).[2] Yet it was not until four years after the first Critique that Kant finally wrote a work on ethics, and even then he merely laid the ground for a metaphysics of morals by identifying and establishing the supreme principle on which a system of duties would be based (G 4:392). Three years later, in the Critique of Practical Reason Kant once again dealt entirely with foundational questions in moral philosophy. Kantian ethics is primarily known, especially among English-speaking philosophers, through these two ethical works of the 1780s, neither of which contains anything like a ‘metaphysics of morals’.