In his ethics Kant emphasizes human free will. In contrast to other objects in the natural world, which are simply subject to natural laws, humans give themselves their own laws. Humans are self-legislating. To clarify the contrast, if I drop a pen to the floor, it doesn’t decide to follow or not follow the law of gravity. It simply follows the law of gravity, as it must, and falls to the floor. Humans are different. While as physical objects humans too are subject to law of gravity and other physical laws of nature, because of our rationality we additionally have a domain of activity that is not subject merely to physical laws of nature. In this domain we provide ourselves with our own principles. We do this, mind you, whether we want to or not. It’s not an option: Each of us simply must provide ourselves with our own subjective principles, which Kant calls maxims. We use these to guide our behavior in the world.
Kant’s ethics, as is well-known, also focuses on the importance of a good will. Yet it is important to see that he understands our will as good, not if have mere good intentions, but only if we choose rational subjective principles. A good will, for Kant, is a rational will. (For more on the distinction between good intentions and a good will see my blog comment.)
Kant’s categorical imperative serves to allow us to determine the specific principles that each of us should accept as our subjective principles (that is, our maxims). In short, the categorical allows us to understand what principles are rational, thus what principles we should adopt in order to have a good will.
Though Kant has various formulations of his categorical imperative, which he calls “formulas,” I will for now only highlight two of them: the universal law formula and the humanity formula. Again, both of these formulas, as well as the others, are to help us understand what principles are rational and thus what principles we should adopt in order to form a rational will.
A Kantian view of practical rationality
Kant’s view of what is rational differs fundamentally from the view of Hobbes or rational choice theorists on what is rational. Hobbes, like later rational choice theorists, views it as rational to act in our own narrow self-interest, and as traditionally formulated, regardless of what that understood self-interest is. Kant disagrees. In Kant’s view, if we are rational, then we cannot act merely to achieve some set of goals that we happen to have. Rather, if we are rational, we will act on the basis of a principle that we can rationally affirm that all others can also make their principle of action.
A conflicting view of rationality and the tragedy of the commons
Let’s reflect on this issue of rationality in reference to the traditional tragedy of the commons to try to clarify this. Imagine 5 fishermen who all have the possibility to fish the same pond sustainably only if they catch 10 fish or fewer per day. (We can imagine that the amount that others take from the pond is very limited and stable. Given the fishing of the five, which is daily, and others, the lake produces enough fish for each fisherman to take ten fish per day.) What should the individual fisherman do? According to the “economic” logic identified with Hobbes and rational choice theory, assuming he needs or can otherwise benefit from more than 10 fish, it is rational for each fisherman to take more than that as long as he can do so without any negative repercussions from the others involved. In fact, given the assumption of the Hobbsean worldview, unless a mechanism for punishment is in place, it would be individually irrational for the fisherman to only take ten fish per day if there is an individual benefit from taking more fish than that, since he must assume that the other four fishermen will all also see it as in their rational self-interest to take more than the sustainable number of fish, given that they can make money from selling the extra fish, or in some other way benefit from that extra fish. And if the one individual fisherman doesn’t deplete the lake, the others will. So, for the Hobbsean, the rational thing for the individual to do is to catch as many fish as possible for himself before the lake is depleted of fish by the others. In the language of rational choice theory this is individually rational. It is however not socially rational. The socially rational action would be to fish sustainably — that is, to take no more fish than can be replenished in the lake. Again, though, given the assumption of rational choice theory that others will not be motivated by good will, but by a narrower self-interest, it is not individually rational for any individual fisherman to fish sustainably if he stands to benefit from doing otherwise. The tragedy of the commons, that is, for public areas like the lake under discussion, occurs because unless there is some means of enforcing limits on fishing, the five fishermen — to remain with our example — will deplete the lake; and over the long haul none of them will then be able to fish the lake. The tragedy in this case is that a lake open for use to these five individuals, which would have been a stable supplier of some food, will become a fishless body of water. Each individual, by pursuing a course of action that is supposed to be individually rational ends up with a long-term situation in which all five fishermen are worse off. In a rational choice scenario, this tragedy could be averted either by a legislative action and adequate policing or privitization of the commons (the lake) with some means of enforcement of property rights.
The universal law formula
Kant disagrees with the view of rationality described above completely. Kant does not distinguish between something individually rational, but socially irrational, or socially rational but individually irrational. His universal law formula of the categorical imperative is to help us decide what is rational, period. That formula states: “Act only on that principle that you can will at the same time to be universal law.” Applying this to the scenario described above, only one thing is rational: Each fisherman should act on the principle that he could will that all others make their guiding principle. He should fish sustainably. In Kant’s view, anything else would lead to a contradiction. Unsustainable fishing undermines the long-term conditions under which fishing is possible, so it would be a contradictory act.
Kant’s universal law formula highlights that we are self-legislating. We are to give ourselves a universal law. His writing on this also highlights the fundamental equality of all people. There is not one law that applies to me and an unequal one that applies to others. One law fits all, at least in theory. (As we will see, this issue in fact is complicated by Kant’s own acceptance of the gender and various other biases of the 18th century. In reality, one size fits all white European men. But for now let’s try to ignore this complication, if we may.)
The humanity formula
Kant seems to have recognized that framing the issues differently with these different formulas would be helpful for clarifying concrete principles. The humanity formula (like the other formulas) is meant to compliment the universal law formula of the categorical imperative. Applying the humanity formula, we should reach the same results as with the universal law formula or any of the other formulas. This framing, though, might help enlighten our thinking in some contexts. Kant’s humanity formula states: “Act only on that principle by which you treat humanity, whether in yourself or in another person never merely as a means but always also as an end.” In Kant’s view, because of the fact that we have free will and are self-legislating (which are both conditions of our being rational), we understand ourselves as being worthy of respect. That same respect that we find that others owe us, we in fact also owe other self-legislating rational individuals. We must thus act on a principle that acknowledges this universal respect or dignity. Perhaps the following is a legitimate short-shift for the humanity formula of the categorical imperative: We must treat ourselves and others with dignity and respect. We should never treat ourselves or others as mere means.
What does it mean to treat someone as a means? Simply put: we should not merely use people. All people deserve to be treated with dignity. There is an operative word in the formulation about means, however. Kant does not say that we may never treat people as a means. He says we may never treat people merely as a means. The lawyerly parsing is important. In principle, Kant does not have a problem with us having use relationships with people, or putting ourselves in use relationships with others. If we go to a bank teller to ask for change for $100, we are involved in a use-relationship with that teller. This is not unacceptable. Indeed, it is inevitable that we engage in use-relationships with people. What here would be unacceptable is if we were to treat the bank teller with disrespect. So too, Kant does not have a moral issue with employer-employee relationships. An employer hires an employee, paying them for their labor power. This is a use relationship. Kant sees no wrong here per se. The wrong would be if the employer reduced the employee to her labor power, if the employer was in an exploitative relationship with the employee. As long as the employer pays a fair wage, and creates a safe, fulfilling workplace (0r fulfills whatever we rationally deem as necessary for a respectful workplace), all is good in the view of Kant.
Kant thinks that the various formulas of the categorical imperative will help us to decide what principles we can legitimately accept as we self-legislate. In the case of fishing where there is a threat of the tragedy of the commons, we have seen that the universal law formula should lead us to accept that we should fish sustainably. In the case of dealing with bank tellers or employees, we would be able to formulate some other concrete principles. The different formulations can facilitate clearer insights in one case or the other. Kant thinks they lead us unerringly to principles that determine our will as good.