Topic: Groundwork for the Metaphysic of Morals: Preface
Author: Immanuel Kant
Book: Immanuel Kant (1785) Groundwork for the Metaphysic of Morals trans. Jonathan Bennett (2005)
Ancient Greek philosophy was divided into three branches of knowledge: physik, ethik and logik. What is the principle behind that division? (See Image.)
The realm of ethics is in part, its empirical part, determined by our experiences — Kant calls this part ‘practical anthropology’ — but ethics also has a rational part determined a priori through pure reason — this part is the ‘metaphysic of morals’. Practical reason or moral philosophy should be grounded on this rational part. Only moral laws derived from it finds universal application. A metaphysic of morals is indispensable because unless such a metaphysic guides us, our own morality will become subject to ‘corruption’.
For something to be morally good, it isn’t enough that it conforms to the moral law; it must be done because it conforms to the moral law.
Kant’s whole purpose is to develop a metaphysic of morals — which he does with the Critique of (Pure) Practical Reason, published in 1788, three years after the Groundwork. But before he does that, he wants to lay the foundation by establishing the supreme principle of morality. The Groundwork lays that, well, groundwork.
(Why is Kant interested in this endeavour?)
Some people regularly mix up the empirical with the rational, suiting their mixture to the taste of the public without actually knowing what its proportions are; they call themselves independent thinkers. Wouldn’t things be improved … if those ‘independent thinkers’ were warned that they shouldn’t carry on two employments at once because all you get when one person does several of them is bungling?
(Ethics) must be carefully cleansed of everything empirical, so that we can know how much pure reason can achieve, and from what sources it creates its a priori teaching.