Nigel Biggar’s response to my questions and criticisms regarding his treatment of killing in warfare is both welcome and helpful. It sets the stage for further discussion both of the nature of intention, and of the relation between the doctrines of the sanctity of human life, which Biggar rejects, and a right to life, which he, at least in civil society, accepts.

In my view, shared with Aquinas, what one chooses, one intends. This despite the maxim, deployed by both Aquinas and Aristotle, that choice is of the means, intention of the end. For whatever one sets oneself to accomplish as a means to some end is thereby also an end, even if only a proximate end. So if intention is of ends, it is of means also.

Biggar appears to hold that intention is of ends, and that it is closed off from the means that are chosen. He seems inclined to this view in part as a result of his account of what one chooses when there are inevitable consequences “causally bound up” with what is chosen. I will address this point below. First, however, I point out that even Biggar’s examples seem to speak more to my expansive account of intention than to his narrower account.

Consider again the example from Master and Commander of the sailor who chops the mast to save the ship, although his friend will perish when the mast is lost. What does the sailor intend, according to Biggar? Certainly the “detaching of the mast.” But that itself is a means to the saving of the ship, his ultimate end. So we have good reason, other things being equal, to suppose that means are part of an agent’s intention.

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Are other things equal? Although intuitions about intention are notoriously hazy and often contradictory, few, including Biggar, believe that the sailor need intend his friend’s death. Were he so to intend, he would be a murderer, guilty of intentionally killing one to save many. But to include what the sailor chooses as part of what he intends threatens our natural judgment, Biggar believes, because his friend’s death “was causally bound up with the cutting loose of the mast.” Therefore, if the cutting was chosen, then so was the killing; and the cutting was chosen.

Two other worries can be detected in Biggar’s reply. First, the sailor can be held accountable, or responsible for his friend’s death. This does not mean that he is automatically culpable, only that he must be able to justify what he did. Second, the friend’s death seems neither accidental nor unintentional. After all, the sailor knew what he was doing.

Let’s approach these considerations in reverse order. Aquinas, who thinks that one might drink wine to excess for the sake of the taste knowing full well that drunkenness will ensue and yet not intend drunkenness, also thinks that it would be crazy to describe the drunkenness as “accidental” or “unintentional.” For, alas, drunkenness is the natural and expected consequence of excessive drinking. Moral: “accidental” and “unintentional” are not, for either Aquinas or us, coextensive with “not intended.” An effect can be outside the intention, yet also not accidental, and not unintentional.

This, in part, is why we might very well hold agents responsible for some foreseeable effects that were not intended. They were not only foreseeable, but entirely to be expected. One could have chosen otherwise, and been free of the noxious effects. So one must have a good reason for doing what one did, such that one was justified in accepting these side effects. And note: acceptance is a form of willing, even if it is not a form of intending. It is completely unlike one’s relationship to effects that one does not and cannot see coming. This is surely why Aquinas holds that although God neither wills moral evil to be done, nor wills that it not be done, still, He “wills to permit evil to be done.” Here, permission—what I am calling acceptance—is clearly indicated by Aquinas to be a kind of willing, but one essentially different from intending.

God sustains all of us in existence: that sustaining causality is necessary for us to make any choice, including a wicked one. Is that not an instance of God’s willing being “causally bound up with” human beings’ sinful choices? Yet, it seems, God does not choose those sinful choices.

And likewise, when our medication is causally bound up with adverse side effects, we accept but do not choose those effects, even though by choosing otherwise we could avoid them. For what we settle on in choice is what we judge needful for the accomplishment of those further ends we pursue as good. And many side effects, causally bound up with the means, simply do not stand in that relation to our ends. In no way needful, they are in no way intended, though we can be held accountable for them.

Now, in neither of the two disputed cases that Biggar and I discuss—the mercy killing of a soldier and the killing of Théoneste by his brother—is the death outside the intention in this way. The death is needful in both cases: to bring about an end of suffering, in the absence of some other palliative measure, and to prevent the killing of the entire family. Those killings are chosen, and thus intended, Biggar’s claims to the contrary notwithstanding. So given the principle “no intended killing of the innocent,” I think both forms of killing are impermissible.

Most thinkers of the natural law tradition would agree, but Biggar believes not all. He points to Vitoria and Grotius as thinkers who accepted a view like his: by his lights, both thinkers endorsed what he would call chosen killing of the innocent. I am less certain. Vitoria’s discussion is framed by his assertion that it is “never lawful in itself intentionally to kill innocent persons.” So far, Biggar and I would agree. Does Vitoria think that one can choose to kill them? The example he gives suggests that this is not what he has in mind: that “during the justified storming of a fortress or city, where one knows there are many innocent people, but where it is impossible to fire artillery and other projectiles or set fire to buildings without crushing or burning the innocent along with the combatants.” This seems a clear case of collateral damage of the choice to bombard the enemy. Damage to the innocent here is neither intended as an end, nor chosen as a means.

The Grotius case is different: the enemy is threatening war unless we turn over an innocent citizen. Do we choose that innocent’s death in turning him over? Leaving aside the question of whether it might still be wrong, even if his death were not intended, to turn over the citizen, it seems plausible that the death of the citizen is not intended by the authorities who turn him over. They acquiesce in the request to avoid sanction. But it is only the enemy who chooses to kill.

Returning to the moral heart of the matter: Biggar believes that choosing to kill an innocent is something that can be done only in a “state of nature.” In political society, willingness to allow such killing would leave too many, particularly the old, the weak, and the otherwise vulnerable, at great risk. So Biggar does not support mercy killing in a political state, even while thinking it permissible in principle (in grave circumstances).

There is an interesting convergence here between Biggar’s views and my own. It is the business of the state to maintain justice. But justice is interpersonal, and injustice is always against another’s will. So there might well be cases, and the cases mentioned by Biggar might be instances, of killing that I would consider intentional, that are not unjust: they are performed on oneself, without violation of other obligations, or they are done with the consent of the victim.

Such killings are still morally wrong in my view: human life is a basic good, and we should never choose to damage or destroy instances of that good by intentionally killing. Yet, considered just in themselves, such killings might seem outside the authority of the state: they involve no injustice.

The sorts of considerations that Biggar mentions in his response, and in his book on killing, however, show that in fact these killings do have wide ramifications in justice, by threatening those who will inevitably be put at risk of unjust killing in a state that permits some not unjust (even if morally wrong) killing. Such considerations, which may also be found in work by Joseph Boyle and Germain Grisez, John Finnis, and John Keown, show that as a matter of political morality, intentional killing of the innocent should under no circumstances be legally permitted.

But we should ask ourselves the following question: Which view of morality, shared as a part of a broader culture, is likely to be helpful, and perhaps even necessary, to support the sorts of political decisions that Biggar and I think are essential? As the broader culture becomes convinced that choosing to kill an innocent human being is not in principle impermissible, it seems likely that they will gradually become convinced that the threatened injustices can be prevented or staved off. The will to rule out, absolutely, physician-assisted suicide and various forms of euthanasia will wane. This seems to be the case in much of the Western world today.

That is not an argument for my view of intention, nor for my view of the sanctity of human life. But it is an illustration of why these questions matter, not just morally, but culturally and politically as well.