If we assume that there is no afterlife, what reason do we have to comply with a person's wishes as regards treatment of their corpse? In particular, it is striking to me that we should respect a person's wish not to extract their organs after death; what reason could we possibly have to heed the wishes of someone who no longer exists, especially when the donation of their organs could literally save the lives of several people?

May I refer you to my answer to question 1114?

I fully agree with you that organs could save lives, very many lives each year, not to speak of health improvements. But nearly all of this problem can be solved rather easily by reversing the standard default. Instead of assuming that a person who dies without leaving specific instructions does not want his or her organs to be used, we should stipulate the opposite. We should institute easy and convenient ways for people to register their veto against the posthumous use of their organs. And we should then assume that all who have not registered such a veto are consenting to the posthumous use of their organs for saving the lives or restoring the health of other people. This simple change in the law would give us the needed organs without the problems I discuss in the response to Q1114.

Let me try to tackle a different aspect of your question: Why should we respect the wishes of someone who has died? This depends on how you view harm, and whether you think someone can be harmed after his or her death. One way of thinking about this question is to think about whether someone can be harmed even if that harm does not impinge on their experiences in any way. Think of Truman in the movie The Truman Show, and imagine that the producers of the show were just a little more skillfulat keeping the deception going, so that it really was completely seamless. Truman never knows that he is being deceived, and from his point of view, his life is just find and dandy. So is he harmed by the deception? If, like me, you have the intuition that he is -- even though he doesn't know about the deception at all and even though the deception has no negative impact (in fact, it has quite a positive impact) on his experience -- you have some inclination to accept that harms can exist outside of experience. And that opens the door to the claim that you can be harmed after your death. If that's the case, then we have an easy explanation for why we should respect your wishes: not doing so would harm you.

These reflections are by no means definitive, but I hope they help show some of the philosophical issues in the background of the question you raise. Many of the essays in The Metaphysics of Death (a great collection on death edited by J.M. Fischer) address these issues in a lot of detail.

A further consideration is that, given that many people have strong wishes -- whether rationally grounded or not -- that their corpses and probably those of their loved ones be treated in certain ways, it would be highly upsetting to many if they were to become aware that such treatment quite possibly wouldn't be provided. In other words, even if you can't harm someone after they are dead, you can harm the living by treating the dead in ways of which the living disapprove.

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