In what sense is being put to death a punishment? How we can talk about things like "suffering" or "loss" if a person is dead (i.e., not conscious)?

It is true that, once a person has been executed, she is no longer around to suffer the loss of years she might otherwise have lived. But the point of an execution is not to punish the person after she's dead, but before. She is subjected to the experience of living on death row and later to the experience of being killed in the execution chamber; and she must expect all along that many things she cared for are less likely to thrive or to come to fruition.

You might respond that this answer works only for people who know about their impending execution. What about someone who is killed painlessly in her sleep? Could this ever be construed as a punishment?

We can give an affirmative answer if we think of punishment in a somewhat extended sense as the setting back of a person's interests. Suppose you have given offense to someone and, in order to punish you, he has been embezzling money from your account. Being an affluent entrepreneur, you never notice the losses (you rather take your business to be less successful than it really is). But, nonetheless, there is a sense in which he really succeeded in punishing you.Your wealth is something you really care a great deal about, and ithas really been substantially dimished over time below what it would be if he had not siphoned off money from your business account. Similarly, you might be punished by someone who is spreading false rumors about you that damage your reputation among the people who know you -- even if no one confronts you with these rumors and you thus remain ignorant of how your reputation has been gravely damaged.

Once we allow that there can be plausible cases of unexperienced punishments, then it may also be plausible to say that someone is punished after her death by setting back interests that were important to her. (After all, if the punishment is not experienced anyway, why should it matter whether the punished person is capable of such an experience at the time of the punishment?) By destroying the reputation of someone after her death, one can reduce the value of her life as she thought of it -- and likewise by destroying her best artwork (which she had ardently hoped would be admired by posterity).

Of course, this is stretching the ordinary notion of punishment a bit, but not, I believe, beyond recognition.

Most of Thomas' response focuses on your observation that once one's dead one's "not conscious", and he nicely tries to clear a space for the possibility of harm's being done to someone even if that person doesn't feel the harm. But in most of the cases he considers, there is still someone to be the subject of the misfortune: the clueless entrepreneur, for instance, is still around to have his interests set back (even if he's not aware that that is happening). Death is rather peculiar, however, in that it's a misfortune that eliminates from the world the subject of the misfortune. (Of course, someone's death might be a misfortune for others. But as you note, we put people to death to punish the very people who, if the punishment is carried out, are no longer around.) Once one's dead, not only does one cease to experience things but one ceases to have interests too. That's what makes your question hard. It's really the question the Ancients (and everyone else) argued about: whether one's own death is a misfortune for one. As one of my students asked when we were discussing this in class, "So murder is a victimless crime?"

Of course, murder is not a victimless crime! But how can that be, Alex asks, if the victim no longer exists in order to suffer the harm that has been done to him? If you must exist in order to have interests, then how can a dead person’s interests suffer as a result of his death?

To see the harm that is suffered by a murder victim, let’s think first about what it means to be harmed. If I were to harm Harry, what sort of thing would I have to do him? Intuitively, when I harm Harry, my actions make him worse off than he would have been had I not acted as I did. So when I spread vicious gossip about Harry, I have harmed him because, had I not spread the vicious gossip, his reputation would have been intact, and he would have been well-respected in his community, loved by his family, and able to complete more easily certain projects about which he cares deeply, projects that require the good will and cooperation of others. Because of my vicious gossip, Harry is now a social outcast, unloved and unaided.

So let’s try out this definition of harm:

X harms Y if and only if X’s action A makes Y worse-off than Y would have been, had X not performed A.

But now, it seems, we have a problem. If I kill Harry, how can we compare the state that Harry would have been in, had I not killed him, to the state that he’s now in, namely, dead? Since he is dead (and we’ll suppose, non-existent), he’s in no state at all. How can we compare this "non-state" to his state he would have been in had he been alive?

The answer to this puzzle, I think, is this. If Harry had survived, he would have attained all of the goods that generally come with living– pleasure, deep relationships with others, philosophical knowledge . . . (complete this list with whatever you count as genuine goods). Of course, had he lived, it’s likely that he would have had some hard times, too– some pain, frustration, heart-break, and so forth. But so long as his life would have been worth living for him, the goods that he would have had, had he survived, would have outweighed the bads that he would have had, had he survived. When I kill Harry, I prevent him from attaining these goods.

When we attempt to figure out the harm that Harry has suffered when I kill him, we should not compare Harry’s state after his death to the state that Harry would have been in, had I not killed him: for the reasons that I give above, such a comparison is impossible. Instead, when we attempt to figure out the harm that Harry has suffered when I kill him, we should compare the totality of goods that Harry would have had over the entirety of his life, had I not killed him, to the totality of goods that he had actually attained in the life that I cut off. If his life would have been worth living, then I did indeed harm Harry when I killed him: I deprived him of all of the goods that he would otherwise have had, had I not killed him.

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