• 3.5: Kant's Metaphysics of Morals

    • Immanuel Kant's Fundamental Principles of the Metaphysics of Morals: Second Section and Third Section

      Read the Second Section from Immanuel Kant's Fundamental Principles of the Metaphysics of Morals. Kant says five things are clear: 

      1. The origin of moral concepts is entirely a priori in reason.
      2. Moral concepts cannot be abstracted from empirical knowledge.
      3. The non-empirical, pure, nature of moral concepts dignify them as being supreme practical principles.
      4. This value of moral concepts as pure and thus good practical principles is reduced if any empirical knowledge is added in.
      5. One must derive for oneself and apply these moral concepts also from pure reason -- unmixed with empirical knowledge.

      Do these claims seem as clear and correct to you as they do to Kant? To what does Kant's concept of the Categorical Imperative refer? Kant gives a second version of the categorical imperative. He calls it the "practical imperative" there, and interpreters sometimes call it the imperative of dignity or of human dignity. Can you describe that version of the categorical imperative?


      Kant says these two versions of the categorical imperative ultimately say the same thing. Can reason why he might think this?

      Unlike the method you have been employing so far in this course, Kant's view is that morality is not something that can be derived from examples. What he wants is to find universal principles of morality that spring wholly from reason and not from experience. This is why he calls his system metaphysics of morals. In the second section, Kant argues forcefully against utilitarian (or popular) moral theories, and he puts forward his own, absolutely binding moral principle: the categorical imperative. In Kant's ethical theory, a categorical imperative is a universal command, a principle that should be followed by anyone in any situation. If a command like "always tell the truth" can be chosen and represents a moral rule we all should follow, then it has the status of a categorical imperative, and is therefore a duty. Kant's examples in this section are meant to show that actions can only be considered truly moral if they are motivated by the duty to follow this imperative.

      Explain what Kant means by autonomy and heteronomy. Kant gives a third version of the categorical imperative in this section. What is this version? Kant is concerned here that our principles of morality must come from ourselves and from our own rationality. However, he thinks of our rationality in universal terms, not as our own individual persuasion or opinion. Rationality and rational morality is always an objective science for Kant.  


      In the Third Section, Kant presents his view of what human freedom consists in, namely, following our rational principles rather than being guided by our appetite for please and our desire to avoid pain. Because Kant has based both freedom and morality on rationality, this means that to be free is to be moral. Or, in other words, to be free is to be bound by our duty to ourselves.

    • 3.5.1: A Kantian Analysis of Lying

      • Harvard University: Michael Sandel's "A Lesson in Lying" URL

        Watch this lecture until 22:29. While you watch, consider this question: can Kant possibly be right that it is never permissible to lie? At first, Kant's idea that duty and autonomy are compatible seems very counter-intuitive. In this lecture, Sandel helps us make some sense of this view, and he applies it to the example of lying. Ordinarily, we might think that lying is morally impermissible most of the time, unless it would help us avert some worse harm. Kant famously denies this commonsense view, asserting that even if we were sure that some great harm was to result from our failing to tell a lie at the right moment, the lie would still be immoral, since it would mean that we failed to respect the moral law that springs from our rationality.

    • 3.5.2: The Ethics of Lying