Is the road to hell paved with good intentions? Yes and no. Yes, if we think that it’s enough to intend a “greater good” and overlook the means to achieve it. Why so? Because evil means distort the supposedly greater good. There’s a commonsense point at issue. To intend the end is to intend the means to the end. But suppose we choose good means to realize the good that we intend? Then our road is indeed paved with good intentions and it leads to heaven and not hell.

So intentions matter. St. Thomas Aquinas explains that one’s intention serves as the very form of one’s act. That is, one’s intention makes one’s act to be what it is rather than some other act. The difference between a mere physical behavior and a human act is precisely the intention that shapes the behavior into a specific act. Moreover, while no merely physical behavior is of moral significance, every human act is.

Here’s an example that helps illustrate why intention matters and what it is. Recently a theologian, discussing end-of-life issues, told his listeners that what counts as burdensome and repugnant medical treatment depends on the intentionality of the person suffering and not on an observer’s judgment. Well, maybe. But a written question raised a critical point. “What if the patient who is suffering finds life repugnant, and for this reason wants to stop eating and drinking to hasten death?” The theologian’s answer, though buffered, included a zinger: “We are not the Intentionality Police.”

This flippant answer suggests muddled thinking. Why? Because if we don’t have a good idea of what a person’s intention is, we don’t know what the person is doing or saying. We’re left with nothing but a physical behavior. We have a responsibility to care for our lives, and so we can’t refuse to eat or drink unless eating or drinking itself worsens our suffering. If a patient refuses basic care because of his or her judgment that life is repugnant, it’s clear enough that the patient intends to hasten death as a means to escape suffering. In any case, it isn’t for us to so hasten the patient’s death.

Muddled thinking often involves self-referential contradiction. The theologian answers a question to offer guidance. But we don’t know this unless we know his or her intention. After all, maybe the answer is a “dry run” for an upcoming exam, a coded message for someone in the audience, or even a bad joke. That none of these options seem plausible reflects that in the context of a public forum the theologian intends what such words ordinarily convey. So, too, when a patient indicates that he or she wants to hasten death because life is burdensome, it’s not a matter for the police to figure out the patient’s intention.

Context, to be sure, always matters. Human acts do not take place in a void and, at the most fundamental level, context helps provide the matter that intention forms into a specific human, and hence moral, act. Intention is not an utterly private phenomenon. I cannot, for example, rob a bank while secretly intending only to use the currency as wallpaper.

A last point: I think the theologian’s answer, though flip and muddled, was well intentioned. But that’s not enough, because getting clear about what intention is, and is not, matters greatly.