A train is hurtling down the tracks. Ahead of it lies a group of five people, tied to the tracks and unable to escape. The only way to save their lives is to switch the train onto a different track—a track on which only a single person is tied down. You stand at the lever that can switch the train. No one else is around. No other options are available to you. What should you do? Kill the one to save the five, or let the five die because you refuse to kill the one?
For the past fifty years, scenarios like this one have played an outsized role in popular and academic discussions of moral decision-making. Such discussions are not, perhaps, without some value. But one of their bad effects is the way they invite us to conceive of the moral life as a series of decontextualized choices between strictly fixed options, with the outcome of each one guaranteed in advance. Kill the one or the five will die. Torture the terrorist suspect or the plane will be hijacked. Lie to the Nazi soldier or he will certainly find the Jews who are hidden in your basement. What’s missing is the role of creative practical thinking—what the scholastics called prudentia—in considering the possibilities and determining how to act. Also missing, the importance of reflection on how we got here—what the decisions are that we and others made to land us in a morally challenging situation. Here I am, standing alone at a lever in a railyard, the lone person responsible for the lives of five captive people…well, what in the world can have happened to me? Did I get involved with a bad set, perhaps? Isn’t this a thing we ought to be thinking about, if we want to think about how a person ought to live?
When moral life is conceived of as a series of fixed choices, each of which arises in what might as well be a vacuum, a natural response is to evaluate those choices simply in terms of the number of people affected: in every case, the correct thing to do is the thing that will minimize suffering. This response is natural, but not inevitable. We can and must consider not only the consequences of our possible actions, but also those fixed principles that rule certain options out no matter the situation we are in. It is precisely for this reason that prudence is so essential. Such is the consistent teaching of the Church through its history: that one must never do evil—not even to avoid a seemingly greater evil or achieve a very great good. The teaching can be a difficult one. Sometimes it calls for great sacrifice. But the Christian’s commitment to it is rooted in our confidence that the world is in the hands of a loving and provident God, whose commands are just and ordained to our own happiness. This, again, is the unbroken teaching of our Church. And it is hard to see its rationale when we allow the moral life to be construed in the way that we have just described, as a series of fixed choices that may as well have no history or wider context.