《應用倫理評論》第 59 期,2015 年 10 月,頁 25-49 The Ethics of Killing, an Amoral Enquiry∗ Cheng-Chih Tsai ∗∗ Abstract In 'What Makes Killing Wrong?' Sinnott-Armstrong and Miller make the bold claim that killing in itself is not wrong, what is wrong is totally-disabling. In 'After-Birth Abortion: Why Should the Baby Live?' Giubilini and Minerva argue for allowing infanticide. Both papers challenge the stigma commonly associated with killing, and emphasize that killing is not wrong at some margins of life. In this paper, we first generalize the above claims to the thesis that there is nothing morally wrong with killing per se, so long as it is instant and unannounced. Then, from the perspective of social evolution, we explain why people refrain from killing others, the general guideline being that it is unadvisable to kill someone with whom you associate a Second Person Perspective (SPP). Finally, drawing from a seminal paper of Press and Dyson on the Iterated Prisoner's Dilemma, we stress that an SPP without an SP (Second Person), or the other way around, can both lead to unwelcome results. Keywords: killing, totally-disabling, infanticide, second person perspective ∗ This research is partly supported by the Ministry of Science and Technology, Taiwan, under grant number MOST 102-2410-H-715-001-MY3. ∗∗ Associate Professor, Center of Holistic Education, Mackay Medical College. E-mail: cctsai@mmc.edu.tw Applied Ethics Review, Vol. 59, 2015, pp. 25-49 The Ethics of Killing, an Amoral Enquiry 27 The Ethics of Killing, an Amoral Enquiry Cheng-Chih Tsai 1. The Ethics of Killing In 2002, McMahan lured us away from the Old Testament paradigm 'Thou shalt not kill', to seriously consider the Ethics of Killing at the margins of life, raising issues such as, at one end, abortion, and, at the other, euthanasia. Ten years later, we witnessed two further attempts to shift the frontiers of acceptable killings away from the two ends - that is, at the beginning and near the end - of life. On the one hand, in Sinnott-Armstrong and Miller (2013) the authors ask the general question 'What makes killing wrong?' and claim that modern medicine has made it possible for us to distinguish between killing and totally-disabling, and that it is the latter rather than the former that harms a person. In effect, the authors suggested that the earliest possible time for killing a person legally can be much earlier than her natural death, and this allows doctors to procure vital organs from a totally-disabled, but not dead person, while her organs are still warm. On the other hand, Giubilini and Minerva (2013) tried to push the 28 《應用倫理評論》第 59 期 latest acceptable time for killing a pre-person - as the authors may have said - further away from its conception. In particular, they claimed that just as in the case of abortion, people should be allowed to practice infanticide without giving any reason, so long as the infant is young enough. The grounds for these two claims are familiar accounts in the ethics of killing, namely, the non-person, the harm, and the deprivation theories. According to the non-person account, a fetus is not a person, so while killing a person is generally wrong, killing a fetus is not. Given that at the earliest stage of an infant, it is no more a person than a fetus is - the viability of an individual need not be dependent on where its position is relative to its mother's womb - early stage infanticide is justified. Similar reasons sometimes are given for the legitimacy of killing someone in PVS - because it is no longer a person, but rather a living corpse. According to the harm account, killing is wrong because it harms the victim. Given that a totally-disabled person is already "totallydisabled", there is nothing wrong with killing that person as he simply cannot be further harmed. Similar considerations can be applied to the killing of fetuses, embryos and zygotes, as they may not have developed a mental mechanism that allows them to feel the harm.1 According to the deprivation account, killing is wrong because it deprives the victim a potential, a possible "future like ours". So, 1 Can we harm an apple? Probably not. The Ethics of Killing, an Amoral Enquiry 29 naturally, the proponents of this theory might not want to accept the above mentioned argument for infanticide. They not only insist that the deprivation of the potential to become a person harms the individual but also maintain that the harm can be there even if the victim himself is not there to feel it, cf. Nagel (1979), Nozick (1981), and Feinberg (1984). However, as Giubilini and Minerva rightly put it, had a person not been conceived then no person is deprived of a potential to be a person - it is not a person at all. So, infanticide cannot be easily refuted by the deprivation theory. Before we go on to say more about the ethics of killing, let us pause for some thoughts on the truth condition of a death statement. According to the Fregean schema, 'John is tall' is true if the referent of 'John' lies in the denotation of 'is tall', and presumably 'John is dead' can be analyzed in the same way. But, if we look more closely at the evaluation of a token sentence of either of the two sentence types, we would find that the truth condition of it amounts to, rather, a sentence of the form 'John's x fails to meet the y-condition at t' for some x, y and t. The case for the tallness of John can be easily prescribed in terms of his physical body, while for the case of death, some possible candidates for the x are (i) heart, (ii) brain stem, and (iii) cerebrum, and each of them can be given some practical criterion y. This is the simplest reading of a death statement, and I would term it the 'Type-I' reading of a death statement. Type-I death statement is easy to analyze because the referent of the subject is easy to be located, and it can either be conceived of as a temporal slice of a B-theoretical being or simply be conceived of as an 30 《應用倫理評論》第 59 期 A-theoretical entity. In either case, the identity of the subject can be established physically. However, the tendency,2 in most countries, of trying to shift from (i) to (iii) in defining death reflects the fact that, when death is concerned, what we care most is whether the "mind" of the person is still around. Classical arguments for the essentiality of cognitive power for personhood can be found in Fletcher (1975) and Singer (1985). In sum, many people think that the subject of the sentence in question refers to something with cognitive power, and I shall call this approach the "Type II" reading. As I have hinted earlier, the Type I reading differs from the Type II reading in that the former is concerned with the physical identity of the subject, yet the latter is concerned with the personal identity of the subject. In particular when a person is dead in the Type II reading, it amount to asserting that a past person is no longer around rather than that a present person has the property of "being dead". 2. The Absence of the Victim According to the Type I reading, the killing of John amounts to the stopping of certain biological functions of John at a specific time. So, after the death of John, the referent of John is still around, and it can be identified with his corpse. In this sense, disregarding the complicated 2 It is only a tendency that I am talking about, and I by no means mean that some countries have already reached (iii). The Ethics of Killing, an Amoral Enquiry 31 social connections that might be related to John and the pain he might experience during the dying process, the killing of John is not much different from the killing of an animal, and my Mountain Goat Fantasy helps to illustrate that in this situation John cannot be the victim of the killing. The Mountain Goat Fantasy Jack is the only goat which lives on a mountain top and it has been in solitude, if that is the right word, for three years. Having no family, no friend and no spiritual faculty that allows it to communicate with God, this handsome goat just lives from day to day enjoying itself. One day, a hunter in ambush shot Jack dead with a magic bullet that instantly took its life. Given that Jack has experienced no panic beforehand, no pain during the dying process, which we assume to be under a nano-second, and no feeling whatsoever after its death, was Jack harmed by the hunter? Apparently, according to the Type I reading, Jack was not harmed. According to the Type II reading, it is even clearer that in the above case, there is no victim of death. It is as if Epicurus' famous passage 'If I am, death is not. If death is, I am not' still echoes. On the one hand, the insight of Sinnott-Armstrong and Miller (2013) that as far as harm is concerned, the dead are no more harmed than the totally-disabled, serves as a reminder for us that at some stage of one's life there can be no harm done to it, because the person is already gone forever. On the other hand, 32 《應用倫理評論》第 59 期 the insight of Giubilini and Minerva (2013) that if one can employ the non-person argument to support the practice of abortion, then by consistency there is no ground for banning infanticide also reminds us that at some stage of one's life, early infancy say, there can be no harm done to it. The latter case, of course, is complicated by the Future-Like-Ours argument of Marquis (1989). However, an argument against killing a fetus based on a deprivation theory of this sort can be properly explained away in terms of the standard theory of reference in the same way that we would not say that J. F. Kennedy was deprived of his valuable future - Kennedy was what he was, and to talk about things that might happen otherwise is to talk about some other person.3 As a consequence, the novictim analysis can be illustrated by the following diagram, where the dotted lines indicate where killing should be unconditionally accepted, i.e. where there is no victim, while O, M, S, G, and T stand for the positions suggested in the Old Testament, McMahan (2002), SinnottArmstrong and Miller (2013), Giubilini and Minerva (2013) and the sceptic of the present paper - which is characterized by the position that an instant-killing of someone while she is sleeping is doing no harm to her - respectively. 3 A careful analysis of the reference of a proper name would affirm the same. The Ethics of Killing, an Amoral Enquiry 33 Evidently, if harm theory is accepted, then a competent adult is no more harmed than a totally-disabled individual is when he is killed, so long as we make sure that the process of killing is extremely quick and unexpected and that it is done while the victim is not in a conscious state - ending one's life while asleep is a blessing. I will use my Penman Fantasy to further illustrate this thesis and to convince the reader that the no-victim argument works more naturally than he or she may have expected. The Penman Fantasy While I was in my study reading a book I found a strange passage in it which said 'if you cast the following spell @2%$^@&^*3#&, then the pen in your hand will become a penman and talk to you for two minutes'. I casted the spell with doubt, but it turned out that the pen indeed became a penman and talked to me for two minutes. But after two minutes, the pen was once again simply an unremarkable O M S G T embryo fetus adult totally disabled brain-dead infant 34 《應用倫理評論》第 59 期 pen. I casted the spell again and again, and had altogether twenty minutes of conversation with the penman. But then I decided not to cast the spell any more. Have I deprived the pen or the penman a future? So, according to the deprivation theory, killing an adult instantly is not in itself wrong, because he has not been deprived of any future good, just as the penman was not deprived of any future enjoyable conversations with me when I decided not to bring him back to life any longer, or as a fetus or infant is not deprived of any future when it is aborted. In sum, we are guided by Sinnott-Armstrong and Miller (2013) and Giubilini and Minerva (2013) to conclude that there is nothing wrong with killing an adult so long as we give the "victim" an unexpected, unpainful, unregistered instant kill, in short an u-killing. However, this conclusion is absurd. There must be something wrong here. Have I committed the fallacy of Slippery Slope? I hope I have succeeded in convincing the reader that this is not the case. Or, does this absurd conclusion suggest that both of the two papers have failed to catch the key reason why citizens in a civilized human society generally refrain from killing each other, including the very ill and the very young? We need to find a new ground for explaining why we should refrain from killing an adult, and then, in effect, push the argument toward the two ends of life. In other words, we should go along the following directions. But how? The Ethics of Killing, an Amoral Enquiry 35 3. The Golden Rule and Second Person Perspective Let me restate my position here: so far as the explanation of the wrongfulness of killing is concerned, the harm theory and the deprivation theory are both wrong-headed. They resort to the wrong items to explain the morality of killing, so as to allow us to push their arguments to the extreme and conclude that all u-killings are acceptable. This result is by no means surprising, as the notions of harm and deprivation can be applied to animals as well and surely we would not blame an insect for killing another. Evidently, the ethics of killing needs to be built on other grounds, and I propose an account with two key ingredients: 1) The ground against human beings' killing one another comes in two levels, the primitive level and the ideological level. The primitive level can be demonstrated with the fact that on learning that you are about to take her life, a human agent would normally fight for her life with no reserve; and the ideological level can be illustrated with the fact that in an idealized society, individuals refrain from killing one another so as to ensure that one does not have to worry about someone else murdering her while she falls asleep. As the primitive ground cannot T′ embryo fetus adult totally-disabled brain-dead infant 36 《應用倫理評論》第 59 期 solve the case of u-killing, it is clear that the true ground for not killing at will - or, in more familiar terms, the ground for granting others "right to life" - is, in essence, a social norm which comes from one's idea of "doing to others as you would have them do to you." As a result, we should not blame a lion for killing one of us because it does not have a mind sophisticated enough to appreciate and take part in our ideological social construction. 2) A human being naturally cares for what lies ahead of him, so despite that death occurs to a person only when he is no longer around, the battle field concerning the rights or wrongs of killing normally remains at stages earlier than one's death. An interesting fact to observe is that it is always the living that are discussing and evaluating the harms or deprivations that death may bring. It is also interesting to observe that one often projects his personal identity to a stage well before he can be characterized as a person, or well after he was totally disabled. As a consequence, whether I would grant a right to life - which is by all means a human construction - to certain stage of a person's life hinges on whether I would consider the corresponding stage of mine as some stage of me that I would like others to respect and refrain from hurting. In this aspect, we can start extending the range of our no-killing zone back towards both ends of one's life. In sum, a u-killing itself neither harms the "victim", nor deprives any future good from him, but the worry of a person concerning the possibility of his "premature" death does harm him. The Golden Rule The Ethics of Killing, an Amoral Enquiry 37 prevents us from killing others in our community because we do not want to live with such worries. As to who, or what, counts as another person, Second Person Perspective (SPP) is a sure guide - our nokilling zone does not cover cases in which no SPP is involved. For Sinnott-Armstrong and Miller, the totally-disabled are not associated with an SPP, and for Giubilini and Minerva, fetus and new born babies alike are not associated with an SPP, so we are not to be blamed for ukilling them. So, according to the present account, what matters in the ethics of killing is whether we have killed someone to whom we associate with an SPP. Nevertheless, SPP is, after all, a mental construction rather than something more concrete, such as a second person (SP). Different people may have different attitudes toward a new born baby, or a totallydisabled man. For some, these individuals are persons like us, having perspectives similar to ours concerning their wishes to live, but for others, such SPP's are at best projected to these non-persons. In extreme cases, someone might even prescribe no SPP to a normal adult, because he does not see the latter "inferior" person as a person. However, we shall not return to this problem until near the end of this paper. Second Person Perspective in IPD games Social evolution is a candidate theory for human morality, in general, and human cooperation, in particular, as illustrated in Maynard Smith and Price (1973) and Axelrod and Hamilton (1981). The good, 38 《應用倫理評論》第 59 期 altruistic, or cooperative behaviors may turn out to be just what selection favors, rather than driven by moral imperatives. In particular, even if on a one-off basis it seems rational to cheat in the Prisoner's Dilemma,4 on a long-term basis, one's expected fitness generally depends the behaviors of others. Axelrod and Hamilton (1981) has revealed that kinship and probability of re-encountering are two key factors that shape the evolution of a population, and this suggests that so far as the effect of an act of killing is concerned, one should not merely care about the harm or deprivation that the act would bring to the victim, if any, but also consider the effect that the society as a whole may have upon the killer himself due to the fact that both the victim and the killer are nothing but two members/players of the same society/game. To the author's knowledge, the most vivid demonstration of how essential an SPP can be in determining the outcome of an IPD game is to be found in Press and Dyson (2012). It is shown therein that in the two– player IPD (Iterated Prisoner's Dilemma) game, there exists a ZD (ZeroDeterminant) strategy for a player X to win over her evolutionary5 opponent Y, who, without a theory of mind about X, can only accede to X's extortion. While most people are impressed by the existence of the ZD strategy, I would like to draw the reader's attention to another equally important thesis - which is much more relevant to the topic of 4 The author does not endorse this observation, but the present paper is no place to elaborate on this issue. 5 As Karl Sigmund and Martin Nowak rightly pointed out, on http://www.edge.org, the term "evolutionary" is inappropriate as Y only adapts but not evolves. The Ethics of Killing, an Amoral Enquiry 39 the present paper - namely, a theory of mind, or, equivalently, an SPP, can play an essential role in disarming the ZD strategy. According to Press and Dyson, once Y has developed a theory of mind about his opponent X, the ZD strategy of X may fail to take any advantage of him. The lesson to be learned here is subtle in the sense that although "having a mind" plays a role in IPD, what truly makes the difference is "having a theory of mine" for the opponent. In other words, what matters more is a second person perspective rather than merely a first person perspective. Let us now look more closely at how an SPP, or a "theory of mind" in Press and Dyson's terms, can affect the result of an IPD game that involves a ZD strategy. If X alone is witting of ZD strategies, then the outcome of the IPD depends on whether Y has a theory of mind. In particular,6 if Y has a theory of mind, then IPD is simply an ultimatum game, where X proposes an unfair division and Y can either accept or reject the proposal. If he does not (or if, equivalently, X has fixed her strategy and then gone to lunch), then the game is dilemma-free for Y. He can maximize his own score only by giving X even more; there is no benefit to him in defecting. The latter Y is an evolutionary player who, according to Press and Dyson, is arbitrarily good at exploring a fitness landscape, but sadly this feature 6 Press and Dyson (2012), p. 10412. 40 《應用倫理評論》第 59 期 makes him an easy prey of his extorting opponent. Now, while an evolutionary Y who has not developed an SPP is guided by his instinct to optimize his gain and thus falls prey of his opponent, a Y who has a theory of mind can conceive of the possibility that he can harm himself so as to threaten his opponent X, who, according to this Y, has a mind - and a theory of mind as well - and may reckon the adjustment of her original strategy desirable, because her opponent's not abiding to her extortionate strategy (by harming himself in order to punish her) is threatening to lead her into a situation where she is rewarded with nothing comparable to what she might reasonably anticipate before she comes up with, and actually puts into practice, the ZD strategy. Furthermore, concerning whether X can go to lunch after setting down her strategy against an opponent, Press and Dyson have remarked that 'if she imputes to Y a theory of mind about herself, then she should remain engaged and watch for evidence of Y's refusing the ultimatum.'7 In sum, SPP makes all the difference to whether the innovative ZD strategy would work for an X witting of it when she meets an opponent Y not witting of the strategy. Let me stress that there is a vital distinction between having a mind and having a theory of mind. The ability to conceive and abide by a particular strategy can be taken as the first step towards having a mind. Yet having a mind requires more. To be classified as with a mind, one is supposed to be capable of coping with 7 Ibid. The Ethics of Killing, an Amoral Enquiry 41 changes. But here, having a mind by itself still cannot deliver Y from his doomed fate. As Press and Dyson remarked, 'If X plays a constant ZD strategy, then any strategy of Y's, rapidly varying or not, turns out to be equivalent.'8 What matters is rather whether Y sees X as someone who can rightly conceive of his behaving badly so as to harm both parties as a threat, and, as a result, choose to lift her ZD strategy and invite Y to cooperate with her so that both can be better off. In a similar way, X's having a mind does not in itself prompt her to make a change of her ZD strategy when she is faced with some persistent bad behavior of Y which seems to suggest that he is refusing the ultimatum. It is possible that X simply regards those bad behaviors as something coming from the intrinsic evolutionary drive hardwired into Y. Only when X adopts an SPP for Y can she realize that Y's refusing the ultimatum has to be dealt with "personally" - leaving for lunch while playing with Y can turn out to be a disastrous decision that causes her a great loss, even if by so doing she can still guarantee that Y would not fare better than herself as far as scoring is concerned - because Y's behavior has suggested to her that Y is not governed by a law of nature or an evolutionary (in the restricted sense of Press and Dyson) drive, but rather by a mind capable of envisaging new strategies some of which serve only as a tentative tool to force X to change her extortionate strategy. To sum up, for the ZD strategy of X to work on Y, both X and Y 8 Ibid. 42 《應用倫理評論》第 59 期 need to have a mind (for Y, it is only in a minimalist sense). However, for that strategy to fail - as we would have anticipated it to happen for a real-life situation and is hinted in Stewart and Plotkin (2012) as well - both X and Y have to reckon that their opponents have a mind and a theory of mind as well. For Y, the functioning of X's mind and SPP justifies his non-cooperative action. For X, the functioning of Y's mind and SPP justifies her reaction to Y's reluctance to cooperate. If we look more closely at this situation, we will find that, for the failure of X's ZD strategy, Y not only need to assume that X has a mind, but also need to assume that X knows that he has a mind as well - as mentioned earlier, if X does not reckon that Y has an SPP, she might just go for lunch and leave the ZD strategy as it is in the first place. Similarly, X does not only assume that Y has a mind, she also assumes that Y assumes that she has a mind - as mentioned earlier, if Y knows that X does not have an SPP which can lead her to change her strategy, he would have accepted the ultimatum she proposes, and the apparent threat to harm both would then be explained away as merely part of an original evolutionary strategy. 4. SPP without an SP or Vice Versa, Practical Issues We have seen that SPP plays a key role in our interaction with others. In particular, SPP may affect our decisions of whether to kill a totally-disabled patient and whether to kill an unwanted infant. However, as hinted in Press and Dyson (2012), having SSP without the presence of a second person can be costly for a player. We will now use the real-life The Ethics of Killing, an Amoral Enquiry 43 example considered in Sinnott-Armstrong and Miller (2013) to illustrate this general fact. However, before we look at possible consequences of an SPP without an SP, I should mention an extremist position which eliminates personal identity altogether from the ontology, hence, in particular, the notion of second person becomes meaningless. In Tsai (2013), after examining three core issues in bioethics, a conclusion concerning personal identity is drawn, which echoes Parfit's more general skeptical view on personal identity, cf. Parfit (1984). It is then suggested that, for pragmatic considerations, the roles previously played by personal identity be taken up by agency. However, we shall not get into this subtle and sophisticated matter here, and will simply assume, for most of the time, that we know what a person is. In Jan. 2012, Walter Sinnott-Armstrong and Franklin G. Miller's paper entitled 'What Makes Killing Wrong?' was first published online in Journal of Medical Ethics, and it later appeared as Sinnott-Armstrong and Miller (2013). Comments from Bevins (2013), DeGrazia (2013), Driver (2013), and McMahan (2013) are subsequently included, with the authors' reply to critics, Sinnott-Armstrong and Miller (2013a) in the same issue as well. The main point of Sinnott-Armstrong and Miller (2013), as has been explained earlier, is that modern medical technology has made the distinction between killing and totally-disabling possible, and it happens that the wrongness we used to associate with killing might actually come from totally-disabling instead. Evidently, Sinnott-Armstrong and Miller (2013) is more concerned 44 《應用倫理評論》第 59 期 with a real life issue, namely the abandon of Dead Donor Rule (DDR) - proposed by Miller (2012), Veatch (2008), and Veatch (2010) etc.- than with the philosophical issues that we have been addressing here. For patients that do not meet the criteria of brain death, yet are apparently in a mindless state, or a "totally-disabled state" as defined in SinnottArmstrong and Miller (2013), the current practice in the US is that, with the consent from the patient9 and/or her family, we remove the lifesustaining device and wait until the patient's heart meets the minimal requirement for it to be declared 'irreversible' and then the patient is pronounced dead based on the heart-lung failure criterion and her heart is procured and donated to some other patient. However, if the patient who receives the heart is up walking again, then the doctors amount to 'Reversing the Irreversible', as Veatch quipped in Veatch (2008). Such miraculous deeds can indeed be demystified by simply observing that 1) The death of an individual might neither imply nor be implied by the death of a heart. So the irreversibility of a man's life is not captured by the irreversibility of his heart. Evidently, in Veatch's case, the function of the heart itself is reversible while the life of its former owner is not; as to the new owner of the heart, her former heart is irreversible, yet her previously vulnerable life is reversible. 2) Regardless of whether one can obtain a consistent criterion for the death of the organ donor, the aliveness of the individual by no means 9 In the form of advance directives, of course. The Ethics of Killing, an Amoral Enquiry 45 entails that he is still a person. This is quite consistent with the basic idea behind the brain-death definition of "death" that the healthy, living heart of a brain-dead patient can be procured without guilt. Similarly, a living brain incapable of facilitating the actions of a person can play little role in the context of social evolution. 3) Total-disability does not involve any personal identity crisis which may arise from the swapping or the transplantation of hearts. What matters is the existence/non-existence of an agent capable of generating actions and reactions. The identity of the agent is at best a collective name for the action and reaction that the agent generates. So, as far as I can see, there is no intrinsic reason to stick to the DDR, and, as suggested in Sinnott-Armstrong and Miller (2013), tdisability - or more precisely, the absence of an SP - seems to be a good alternative criterion for vital organ procurement.10 However, the tdisability of an individual, i.e. her ceasing to be a person, does not imply that other persons cannot see her as a person and treat her the way they would treat a person who is able to act and react. In other words, in the absence of a second person - both in the strong sense that there is no person in reality at all, or in the weak sense that the individual in question is not an agent - one's adoption of an SPP definitely has some effects on how the species is to evolve. Apparently, frequent unnecessary fleeing for false alarms - or, analogously, ascribing an SPP to an X who 10 Here, it needs to be stressed that people in deep coma and patients with the locked-in syndrome do not meet the t-disability criterion. 46 《應用倫理評論》第 59 期 has gone for lunch - may be more costly than we think. Furthermore, by spending extract money on maintaining the lives of t-disabled persons, we in effect reduce our chance of survival, both as an individual and as a species. Finally, let us all be warned that, SP without an SPP is, in general, far more dangerous than SPP without an SP. As a corollary of this warning, imagine a human society all of whose members associate no SPP to their infants - a society that Giubilini and Minerva might, or might not, want to endorse - and work out how it would evolve! The Ethics of Killing, an Amoral Enquiry 47 References Axelrod, R. M., and Hamilton, W., 1981, "The Evolution of Cooperation," Science 211: 1390-1396. Bevins, M., 2013, "Dependent Relational Animals," Journal of Medical Ethics 39 (1): 15-16. DeGrazia, D., 2013, "On the Wrongness of Killing," Journal of Medical Ethics 39 (1): 9. Driver, J., 2013, "On 'What Makes Killing Wrong?'" Journal of Medical Ethics 39 (1): 8. Feinberg, J., 1984, Harm to Others, Oxford: Oxford University Press. Fletcher, J., 1975, "The Cognitive Criterion of Personhood," Hasting Center Report 4: 4-7. Giubilini, A., and Minerva, F., 2013, "After-Birth Abortion: Why Should the Baby Live?" Journal of Medical Ethics 39 (5): 261-263. Marquis, D., 1989, "Why Abortion is Immoral," Journal of Philosophy 86 no. 4: 183-202. Maynard Smith, J., and Price, G. R., 1973, "The Logic of Animal Conflict," Nature 246 (5427): 15–18. McMahan, J., 2002, The Ethics of Killing, Problems at the Margins of Life, Oxford University Press. ________, J., 2013, "Killing and Disabling: a Comment on SinnottArmstrong and Miller," Journal of Medical Ethics 39 (1): 10-11. Miller, F. G., and Troug, R. D., 2012, Death, Dying, and Organ 48 《應用倫理評論》第 59 期 Transplanatation, New York: Oxford University Press. Nagel, T., 1979, "Death," Mortal Questions, New York: Cambridge University Press, pp. 1-10. Nozick, R., 1981, "On the Randiant Argument," in Reading Nozick: Essays on "Anarchy, State and Utopia", edited by J. Paul, Totowa, NJ: Rowman & Littlefield. Parfit, D., 1984, Reasons and Persons, Oxford: Oxford University Press. Press, W. H., and Dyson, F. J., 2012, "Iterated Prisoner's Dilemma Contains Strategies that Dominate any Evolutionary Opponent," Proc Natl Acad Sci USA 109: 10409-10413. Singer, Peter, 1985, "The Moral Status of the Embryo," in Making Babies, edited by P. Singer and D. Wells, New York: C. Scribner's Sons. Sinnott-Armstrong, W., and Miller, F. G., 2013, "What Makes Killing Wrong?" Journal of Medical Ethics 39 (1): 3-7. ________, 2013a, "Killing Versus Totally Disabling: a Reply to Critics," Journal of Medical Ethics 39 (1): 12-14. Stewart, A. J., and Plotkin, J. B., 2012, "Extortion and Cooperation in the Prisoner's Dilemma," Proc Natl Acad Sci USA 109: 10134-10135. Tsai, C-C., 2013, "The Unbearable Lightness of Personal Identity - Messages from Bioethics," Applied Ethics: Risk, Justice and Liberty, Center for Applied Ethics and Philosophy, Hokkaido University, pp. 39-51. Veatch, R. M., 2008, "Donating Hearts After Caridiac Death-Reversing the Irreversible," New England Journal of Medicine 369: 672-673. The Ethics of Killing, an Amoral Enquiry 49 ________, 2010, "Transplanting Hearts After Death Measured by Cardiac Criteria: The Challenge to the Dead Donor Rule," Journal of Medicine and Philosophy 35 (6): 313-329.