Justice_ What's the Right Thing to Do_ - Michael Sandel [55]
What Is the Supreme Principle of Morality?
If morality means acting from duty, it remains to be shown what duty requires. To know this, for Kant, is to know the supreme principle of morality. What is the supreme principle of morality? Kant’s aim in the Groundwork is to answer this question.
We can approach Kant’s answer by seeing how he connects three big ideas: morality, freedom, and reason. He explains these ideas through a series of contrasts or dualisms. They involve a bit of jargon, but if you notice the parallel among these contrasting terms, you are well on your way to understanding Kant’s moral philosophy. Here are the contrasts to keep in mind:
Contrast 1 (morality):
duty v. inclination
Contrast 2 (freedom):
autonomy v. heteronomy
Contrast 3 (reason):
categorical v. hypothetical imperatives
We’ve already explored the first of these contrasts, between duty and inclination. Only the motive of duty can confer moral worth on an action. Let me see if I can explain the other two.
The second contrast describes two different ways that my will can be determined—autonomously and heteronomously. According to Kant, I’m free only when my will is determined autonomously, governed by a law I give myself. Again, we often think of freedom as being able to do what we want, to pursue our desires unimpeded. But Kant poses a powerful challenge to this way of thinking about freedom: If you didn’t choose those desires freely in the first place, how can you think of yourself as free when you’re pursuing them? Kant captures this challenge in this contrast between autonomy and heteronomy.
When my will is determined heteronomously, it is determined externally, from outside of me. But this raises a difficult question: If freedom means something more than following my desires and inclinations, how is it possible? Isn’t everything I do motivated by some desire or inclination determined by outside influences?
The answer is far from obvious. Kant observes that “everything in nature works in accordance with laws,” such as the laws of natural necessity, the laws of physics, the laws of cause and effect.13 This includes us. We are, after all, natural beings. Human beings are not exempt from the laws of nature.
But if we are capable of freedom, we must be capable of acting according to some other kind of law, a law other than the laws of physics. Kant argues that all action is governed by laws of some kind or other. And if our actions were governed solely by the laws of physics, then we would be no different from that billiard ball. So if we’re capable of freedom, we must be capable of acting not according to a law that is given or imposed on us, but according to a law we give ourselves. But where could such a law come from?
Kant’s answer: from reason. We’re not only sentient beings, governed by the pleasure and pain delivered by our senses; we are also rational beings, capable of reason. If reason determines my will, then the will becomes the power to choose independent of the dictates of nature or inclination. (Notice that Kant isn’t asserting that reason always does govern my will; he’s only saying that, insofar as I’m capable of acting freely, according to a law I give myself, then it must be the case that reason can govern my will.)
Of course, Kant isn’t the first philosopher to suggest that human beings are capable of reason. But his idea of reason, like his conceptions of freedom and morality, is especially demanding. For the empiricist philosophers, including the utilitarians, reason is wholly instrumental. It enables us to identify means for the pursuit of certain ends—ends that reason itself does not provide. Thomas Hobbes called reason the “scout for the desires.” David Hume called reason the “slave of the passions.”
The utilitarians viewed human beings as capable of reason, but only instrumental reason. Reason’s work, for the utilitarians, is not to determine what ends are worth pursuing. Its job is to figure out