Abstract
This article casts light on the moral implications of the possibility of human extinction, with a specific focus on extinction caused by an interruption in human reproduction. In the first two paragraphs, I show that moral philosophy has not yet given promising explanations for the wrongness of this kind of extinction. Specifically, the second paragraph contains a detailed rejection of John Leslie’s main claims on the (im) morality of extinction. In the third paragraph, I offer a demonstration of the fact that a moral view which stresses the permissibility of some types of human extinction can be effectively constructed, while in the following paragraph I propose a prima facie defense of a new approach to the topic which is likely to provide us with reasons in favor of the wrongness of a premature departure of humankind.
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Notes
As Lenman (2002), p. 254) correctly pointed out.
In his remarkable book on climate change ethics, Gardiner wrote that formulating ethical issues concerning future persons as problems of future generations implies the acceptance of two assumptions: that dividing those who will exist in groups of contemporaries is possible (and useful), and that this is the morally salient way of thinking about them (Gardiner 2011, p. 145). While he is certainly right, it seems to me that we should add an equally controversial meta-assumption: that according to which there will be people in the future.
This fact considerably undermines the usefulness of justice strategies based on a “transgenerational chain of elementary solidarity and fairness that has given and is supposed to continue to give every generation of parents a chance to take care of their children in an Earth that is still in an acceptable state” (Cerutti 2010, p. 498) in avoiding extinction in the long run. The motive is that what is at stake here is the very existence of future parents and children.
One predictable objection might be that, because of some essential features of human nature, such a scenario will be impossible. People – the objection goes – are naturally inclined to have children, and reproduction is a very important step toward happiness and meaning in life - so almost nobody will give up the possibility of having children in order to increase her own wellbeing. I see two main ways to reply to this criticism. Firstly, we could challenge its very content, revealing that the prevalence of reasons to have children cannot be taken for granted (Morgan and King 2001) and that these reasons are perhaps self-interested ones (e.g. Boldrin and Jones 2002). Moreover, social and institutional factors play a major role in promoting fertility (Morgan and King 2001) as well as altruistic behavior (e.g. Fehr and Fishbacher 2003), and the connection between happiness and fertility is still far from clear (Kavdal, forthcoming). Secondly, we may specify our focus in order to avoid the objection. It is quite evident nowadays that we are not making great political progress towards the reduction of global emissions, delaying often sine die the implementation of effective mitigation policies at the international level. Acting this way means worsening the ecological situation which future generations will have to face, also increasing the risk of irreversible, abrupt changes in global climate. Clearly enough, such a behavior is very likely to have a considerable impact on the worthwhileness of future persons’ lives – and it has been estimated that climate change already causes 300000 deaths per year (GHF 2009, p. 9). At present, there are not many reasons to be optimist about a shift to more sustainable policies, given also problems of moral corruption (Gardiner 2011, part E), difficulties in attributing precise individual responsibilities (e.g. Sinnott-Armstrong 2005; Fahlquist 2009) and, at a wider level, the inadequacy of some of our basic moral concepts (Jamieson 1992). In this context, we cannot exclude that, sooner or later, creating someone in a world affected by climate change will become strongly problematic from an ethical point of view – in fact, a correlation between environmental concern and declining fertility intentions has already been observed (Arnocky et al. 2012). This could in a few centuries drive us to a scenario where deciding whether to suffer huge declines in one’s own wellbeing or allow life to become not worth-living for future generations are inescapable alternatives. The question would then be if there was something morally wrong in that course of events.
It may be objected, following Hare (1993), pp. 72–83), that this rejection of the Total Principle is too simplistic because it has the problem, among others, of showing that the transition from the initial population to the latter, enormously bigger one, would not introduce disutilities that would more than cancel out the supposed increase in utility. However, total utilitarianism remains a controversial moral view: it allows us, for example, to break promises, betray our friends, and even to kill our beloved if these acts will produce an even slight increase in total utility - more generally, it could be judged unreasonably demanding. The literature about the several variants of utilitarian moral theory is extensive, and trying to say something definitive about it would far exceed the purpose of this article. What I intend to stress here is only that in its standard formulation, Total Principle seems to have very counterintuitive implications and that, given this fact, it will hardly become a common view of morality. So, if we want humanity to delay its extinction as much as possible due to moral reasons, we surely need a somewhat less controversial basis. Hare himself has tried to develop an innovative approach which bases our duties towards future possible people on a mixture of the Golden Rule and the Potentiality Principle. According to Hare’s formulation of the Golden Rule, “we should do to others as we wish them to do to us” and, as a logical extension, also “what we are glad was done to us”. He uses the Rule against the practice of abortion: “[i] f we are glad that nobody terminated the pregnancy that resulted in our birth, then we are enjoined not, ceteris paribus, to terminate any pregnancy which will result in a person having a life like ours” (Hare 1975, p. 208). Affirming their interconnection (Hare 1975, p. 211), Hare links the Golden Rule and the Potentiality Principle together. As a result, when considering abortion one has to take into account not only the fetus’ human potentiality, but also that of the possible future child who, if the fetus was aborted, would be conceived by her parents – given that the latter can be permitted to have a limited number of children only at the point when the addition of another member of the family or the society would result for the already existing members in disadvantages so considerable to exceed, on the whole, the contribution of the new human being to total utility (Hare 1975, p. 218). In light of this limitation of the duty to procreate, sometimes we have to manage choices “between having this child now and having another child later”. In such cases, we have to do to the others affected, taken together, what we wish were done to us if we had to be all of them by turns in random order (Hare 1975, pp. 212–213). As an apparently reasonable application of total utilitarianism to the ethics of creation, Hare’s proposal seems to allow us to avoid both the Repugnant Conclusion and human extinction. However, it cannot resist a careful analysis. First of all, its application would have strongly undesirable consequences. Imagine a husband who, though loving his wife, is frustrated by her intention not to have an offspring. One day a neighbor friend of his, a forty-year-old single woman, asks the man if he want to have a child with her, who shares his strong desire to raise a baby but lacks a man to procreate with (let us assume, in order to simplify the example, that this story takes place in a country in which donating sperm is forbidden). Given the relationship already existing between them, the man would be able to spend a lot of time with his illegitimate child without make his wife suspicious. Our husband, a good person with interests in ethical theory, decides to make a moral choice following Hare’s method. He imagines himself from the point of view of the possible child, who in a case exists (with a life presumably worth-living), while in the other does not (cf. Hare 1975, p. 213); then he hypothesizes to be in his neighbor friend’s shoes: in a possible outcome she is a quite happy mother, in the other, a sad middle aged spinster; after that he reflects upon his own alternatives, namely to be a faithful and frustrated husband, or an unfaithful but content one. Now it is quite evident that, whatever the importance that could reasonably be assigned to his wife’s preferences, Hare’s reading of the Golden Rule would imply that the husband has a duty to procreate outside his marriage (here I have voluntarily left aside the problems that an utilitarian theory might have in demonstrating that the wife is harmed even if she never comes to know about her beloved's betrayal). This conclusion seems at best bizarre. Moreover, Hare’s general evaluation of possible persons’ preferences ignores some basic facts about human identity. In a choice between two different pregnancies, one already started and passible of interruption via abortion, the other still to commence, Hare seems to imply (p. 213) that there is a possible future child who is able to exist in both cases – and then to express an hypothetical predilection for one of them. Unfortunately, this is biologically impossible - as acknowledged by Parfit (1987), pp. 351–355). In addition to these objections and from a more sophisticated standpoint, we have to note that Hare’s formulation of the Golden Rule is self-defeating (Boonin-Vail 1997, pp. 187–191) and his use of potentiality improper (Reichlin 1997, pp. 2–4). At the end of this quite long discussion, I conclude that we have at least strong prima facie evidence that total utilitarianism, even in Hare’s ingenious reformulation, cannot help us in dealing with the possibility of human extinction.
Another possible popular strategy for demonstrating that extinction is intuitively wrong deserves mention: that according to which we can recognize an indubitable progress behind the advent of modernity and therefore we have to do our part in some greater plan or process (cf. Lenman 2002, pp.59-60). I think that, though mistaken, this strategy is less trivial than it may appear, but I have no room here to address it in detail. A relevant set of complications for proponents of such a view can be found in Wagner (2012), esp. chapter 3).
To my knowledge, Lenman and Leslie are the only contemporary scholars who have written about it. Recently, an increasing attention has been paid to “existential risks”, intending with this definition situations in which “an adverse outcome would either annihilate Earth-originating intelligent life or permanently and drastically curtail its potential” (Bostrom 2002). However, by now such a debate has made only weak incursions in the field of moral theory. Bostrom, for example, argues that because of our strong moral uncertainty in discussing about the importance of far future and the appropriate weight to give to existential risks, we have prudential reasons to keep our options – and then, humankind – alive (Bostrom 2013, p. 24). This view seems problematic: it is very probable that taking into account mankind’s far future in our current moral choices will have considerable costs – and as far as we accept the general principle that “ought implies can” a prima facie consequentialist argument for the most prolonged perpetuation of human species hypothetically possible to us (Bostrom 2013, p. 16) loses a lot of its argumentative strength. Indeed, Bostrom himself admits that “one might advocate that as we become more concerned about existential risks, we ought simultaneously to become less concerned about smaller risks, such as a few thousand people dying in the odd terrorist attack or natural disaster” (Bostrom 2013, p. 29 n. 32). A similar shift in our ethical concerns would imply that the main goal of the future x generations (as well as the present’s, of course) should be the realization of certain conditions – e.g. some kind of scientific progress – enabling all the (immensely more numerous) people who will exist after them to enjoy a life of extraordinary high wellbeing and (now) unthinkable possibilities; but this would be absurdly demanding for every kind of human – as opposed to divine, or super-human - ethics. In fact, devoting one’s life to promote the welfare of persons we will never meet – and therefore, with whom we will never have a significant relationship, at least in the standard meaning of the word – would imply a particularly unattractive form of moral sanctity. As famously remarked by Wolf (1982), it could be not rational (or good, or desirable) to be moral saints, that is individuals “as morally worthy as can be”, because sainthood is incompatible with many of the personalities and ways of life we find desirable.
Leslie admits that moral values, in order to deserve respect, should not be individual whims produced by personal preferences. However, he seems willing to concede that actually this is not the case: “Men feel a need to give special dignity to their moral preferences by supposing them backed, even if unverifiably, by something beyond such preferences – something whose relevance does not itself depend on prior acceptance of a particular set of evaluative norms. Religious practices, through being referred for their justification to something beyond mere whims, gain the kind of importance which they have to those who follow them, and the same goes for the moral practices of most people” (Leslie 1972, p. 218).
More or less explicitly, Leslie made this assertion in all the works I mentioned – in Leslie (1978), he tried even to make some steps towards an explanation of the existence of anything. He also argued that the scientific regularity of the world, together with its possibility to be known and the presence of life in it, can be seen as elements in favor of the belief that its existence and detailed nature are products of a directly active ethical necessity (Leslie 1970, 294–296).
“Many philosophers […] think that some largish number of happy people would be quite enough, morally speaking. For the sake of my story, let’s say the number is seventy-seven billion” (Leslie 1996, p. 181).
It might be objected that this criticism is unfair because, by proclaiming himself a total-utilitarian (Leslie 1996, p. 179), Leslie endorses an ethical principle which allows us, at least in theory, to resolve disputes. However, as we have already seen, total utilitarianism has quite implausible implications in an intergenerational context, so adopting it would not be useful unless some further explanation of how it can be amended is provided. Moreover, endorsing at the same time a version of Neo-Platonism (Leslie 1996, pp. 169–170) and a variant of utilitarianism is not a promising move. Even the Republic, which is, among Plato’s dialogues, the most likely to be interpreted in an utilitarian fashion, “says – as Brown (2009), §6) wrote in his review – that virtuous activity is good not because it brings about success, but because it is success”. Importantly, this view reminds that stated more than seventy years ago by Mabbott (1937), p. 472), who also wrote “Plato’s position seems to me exactly that which would be taken up by any Christian moralist to the proverb, “Honesty is the best Policy”. […] Firstly, [according to Plato] honesty is its own reward. The virtuous state of the soul which honest action expresses has intrinsic value; secondly, honesty has other rewards in the peace of mind which follows it and (he might add) in the life to come. But it does not follow that these rewards are the only or the main incentive to honesty; indeed they need not to be an incentive at all” (1937, p. 473). Things are even more uncontroversial if we turn to Plato’s other works. For example, as convincingly argued by McCabe (2005), Euthydemus contains an articulated – and, obviously, implicit – objection to consequentialism - and we know that utilitarianism is an exemplar of the broader family of consequentialist ethics. So, if Leslie wants to adopt a kind of Neo-Platonism that does not make violence to the very grounds of platonic ethics, he cannot embrace total utilitarianism at the same time – surely not without a long (and probably complicated) argument in favor of the opposite conclusion.
Someone may suppose that, as far as the extinction produced by atomic bombs was painless, a utilitarian would have no elements to criticize it, but this is true only for a – very loose – type of utilitarian theory (Smart 1958). Normally, a person willing to maximize utility has strong reasons to let worth-living lives continue – though, as I will try to show at the beginning of the next paragraph, it is far more controversial that such a maximization would imply the creation of extra worth-living existences.
Assuming that the two individuals at issue have similar levels of wellbeing and comparable externalities on other people’s levels.
Intending here “prenatal” as containing “pre-conceptional”.
That is: literally, not metaphorically (cf. Kott 1987, Appendix II).
For merely euphonic reasons, I am using here “miserable” and “happy” as synonyms of, respectively, “with a life not worth-living” and “with a life worth-living”.
I am making reference to Derek Parfit’s distinction between “technical” and “deep” impossibility (Parfit 1987, pp. 388–389), according to which the latter “requires a major change in the laws of nature, including the laws of human nature”. Leslie’s story contains several deeply impossible features - as he admits in a previous formulation of it: “In the actual world, certainly, it is hard to find “inhabitants of windowless huts”, i.e. people who could not conceivably be helped by us in any way. Perhaps such people would have to be beings inhabiting other galaxies or neutron stars or other exotic locations” (Leslie 1989, p. 31).
Since I have already mentioned them, here I will not recall the implausible (and, for some people, maybe repugnant) implications of total utilitarianism in dealing with merely possible people.
This is not to endorse such a view (see also note 10), but only to demonstrate that it is not counter-intuitive in the way Leslie described.
Generally speaking, it is a matter of the so called “separateness of persons”. In Vallentyne’s words: “Psychological autonomous beings (as well, perhaps, as other beings with moral standing) are not merely means for the promotion of value. They must be respected and honored, and this means that at least sometimes certain things may not be done to them, even though this promotes value overall” (Vallentyne 2006, p. 29). It has often been argued that the separateness of persons offers a potential reductio of any kind of consequentialism. Recently, Norcross (2008) has forcefully challenged this thesis. Though not totally persuaded by his view, I will not discuss it here.
Narveson admits an exception, at least hypothetically: we may have a duty to procreate “[i] f it can be shown that the populace will suffer if its size is not increased” (Narveson 1967, p. 72).
On the view that coming into existence cannot be better or worse for the one who starts to exist see Parfit (1987, Appendix G). A detailed defense of the thesis – which I, as well as the majority of philosophers, endorse – according to which the benefits and harms of coming into existence are only non-comparative (i.e. it can be good or bad, but not better or worse) for the individual at issue, can be found in Bykvist (2007).
I think it is quite clear that a person can be harmed – for example, in the sense of suffering an injury, or being killed – without being affected for the worse: imagine that A is going to kill B and that I cannot avoid in any way the occurrence of the murder. Suppose also that I have the possibility of killing B an instant before A: even if in so doing I would not make A’s condition overall worse, I would still harm him. The following is an example from the context under consideration: creating a child with an incurable disease which will kill her after years of painful life counts as harming her even it cannot be said that nonexistence would be comparatively better from her standpoint. In any case, there are good reasons to believe that comparative harm has greater moral weight than corresponding non-comparative one - see, for example, Woollard (2012), pp. 685–689).
Notice that this problem remains even if we accept that the reason-giving weight of non-comparative benefits is inferior to that of equivalent comparative benefits (McMahan 2013, pp. 31–32). Worse, “the claim that there is a general reason to confer noncomparative benefits by causing people to exist […] also seems to imply, in other cases, what Parfit calls the Repugnant Conclusion” (McMahan 2013, p. 34).
Here I will only deal with Heyd’s theory of supererogation, as it looks particularly interesting for the purposes of this paragraph. For an updated review of the literature on this topic see Heyd (2011). A qualified defense of the existence of supererogatory acts can be found in Heyd (1982), chapter 8). Some arguments against forced supererogation, whose possibility would complicate a bit my arguments in this paragraph, are offered by Haydar (2002).
Notice that I have already sketched an argument which demonstrates that procreation satisfies the second part of the same condition. I will also assume that creating (and rearing in an appropriate way) someone with a life presumably worth-living satisfies condition c).
It is worth remarking that defining the judgment at stake as misleading could generate difficulties in accepting the legitimacy of the (fundamental) legislation about children’s rights. Indeed, if care for one’s offspring is only a matter of natural sentiments and inclinations, how can law effectively regulate such a field? Furthermore, even if we find a way to allow legislation, we have to recognize that there are always exceptions to what we refer to as “natural” – in this context, it is simple to see that some particular persons are not very apt to become parents. Nonetheless, if we are not able to morally impose to them some kind of parental duties, we are forced into an unattractive conclusion implying that their possible lack of respect for legal duties of care connected with their children’s rights is never wrong, or at least always an example of blameless wrongdoing. (Practically, an alternative may be found in asserting that there are moral reasons to prohibit that certain people have children – as proposed by LaFollette (1980)– but I am not sure about it). Someone may raise a further criticism according to which, while there are morally relevant implications (e.g. parental duties) once a new person has come into existence, the decision about someone’s creation cannot be evaluated with moral tools – like the choice to love or not somebody, perhaps. Some interesting remarks on this last point can be found in Lotz (2009).
The other one is related to the gap between intended and actual consequences, which may be dramatic when we choose to bring an individual to life. Indeed, supererogatory acts usually have very high probability to succeed in their aims – with the possible exception of some mediated kinds of charity, perhaps. It might be observed that it is precisely this probability that makes them intrinsically valuable. In fact, if an act is not morally required, justifying it from a moral standpoint in the case it has dangerous possible consequences may be difficult. This is maybe the most serious obstacle my argument has to face. Here I can only give a brief suggestion about a way to overcome it. First of all, we have to notice that, when a person comes into existence, she can be both the main beneficiary of this fact (in a hypothetical worth-living life), or the principal subject of the harm brought about by it (in a hypothetical non-worth-living life). Considered that we are able to make some good suppositions about the worthwhileness of a possible future existence (thanks, for example, to medical technology or to detectable environmental and economic conditions) and that the great majority of us judge their lives worthwhile, procreation usually constitutes a notable non-comparative benefit for the one who will live. But what – a critic could ask – gives us the right to play with probabilities with someone else’s existence, in the end? Brutally speaking, my answer would be “The fact that having an offspring can be an important source of meaning in life”.
“While intention forms part of the description of the act, the motive is only the “feeling” which moves us to do it […]. The motives for acting supererogatory are diverse in character, and are not always virtuous. One may act heroically in order to gain fame, to soothe one’s conscience (haunted by guilt feelings), or out of moral self-indulgence. […] Although the motives of supererogatory acts may be self-regarding, the intention must be other-regarding. And only other-regarding duties can be surpassed supererogatorily” (Heyd 1982, p. 137). Therefore, in order to satisfy d), procreation should be guided by another-regarding intention. It is a demanding requirement, though probably not an impossible one.
In its formalized version, the Restriction consists of two propositions: “a) If outcome A is better (worse) than B, than A is better (worse) than be for at least one individual. b) If outcome A is better (worse) than B for someone but worse (better) for no one, then A is better (worse) than B.” (Arrhenius 2009, p. 292). In any case, given the number of apparently paradoxical implications that the Restriction generates according to Arrhenius (2009), this departure may be essential for the stability of the arguments developed in this paragraph.
Even if it must be recognized that Huemer (2008) provides interesting arguments in defense of the choice of Z over A.
Zaitchik (1982), p. 246) summarized them as follows: “(a) although a man’s acts of fraud and covenant breaking may occasionally go undetected, and hence, rewarded, it is impossible to reliably predict when he will escape notice and when not; (b) the consequences of being found out as a covenant breaker include exclusion from all future “confederations”; (c) exclusion from confederations spells death in the state of nature; (d) therefore it is generally an unwise policy to fail to perform second in the state of nature”.
Obviously, here I am taking for granted the presence of some adaptation policy, without which high emissions will not result in an increase of welfare, not even for a brief period.
For a classic philosophical account of the concept of gratitude, see Berger (1975). According to Heyd (1982), p. 140), “[g] gratitude is always appropriate in the case of supererogatory behavior”. Keller (2006), pp. 259–262) provides good reasons for thinking that filial duties cannot be construed (only) as duties of gratitude, admitting at the same time the possibility of duties of this kind towards our parents (Keller 2006, p. 258). Formulating our duties to ancestors in terms of gratitude and fairness has the advantage of allowing us to avoid the use of an ambiguous concept as “posthumous harm”- since a lack of gratitude, or fairness, can happen even in the absence of a harm. As an example, I could send 1,000$ to an NGO which tries to safeguard some native Americans’ traditions without being thanked by its officials, who really appreciate only donations greater than 3,000$, but this lack of gratitude would represent a small inconvenience, not a harm.
For example, we cannot ask individuals to put at risk the worthwhileness of their existences to safeguard that of possible future people’s lives.
References
Allen, W. (1991). The complete prose of Woody Allen. New York: Wings Books.
Archer, D., & Brovkin, V. (2008). The millennial atmospheric lifetime of anthropogenic CO2. Climatic Change, 90, 283–297.
Arnocky, S., Dupuis, D., & Stroink, M. L. (2012). Environmental concern and fertility intentions among Canadian university student. Population and Environment, 34(2), 279–292.
Arrhenius, G. (2009). Can the person affecting restriction solve the problems in population ethics? In M. A. Roberts & D. T. Wasserman (Eds.), Harming Future Persons (pp. 289–314). Dordrecht: Springer.
Beck, U. (2010). A God of one’s own: religion’s capacity for peace and potential for violence. Cambridge: Polity Press.
Beckerman, W., & Pasek, J. (2001). Justice, posterity, and the environment. Oxford: Oxford University Press.
Bennett, J. (1978). Maximizing happiness. In R. I. Sikora & B. Barry (Eds.), Obligations to future generations (pp. 61–73). Philadelphia: Temple University Press.
Berger, F. R. (1975). Gratitude. Ethics, 85(4), 298–309.
Blustein, J. (1997). Procreation and parental responsibility. Journal of Social Philosophy, 28(2), 79–86.
Boldrin, M., & Jones, L. E. (2002). Mortality, fertility and saving in a Malthusian economy. Review of Economic Dynamics, 5(4), 775–814.
Boonin-Vail, D. (1997). Against the golden rule argument against abortion. Journal of Applied Philosophy, 14(2), 187–197.
Bostrom, N. (2002). Existential risks. Journal of Evolution and Technology, 9, 1–30.
Bostrom, N. (2013). Existential risk prevention as a global priority. Global Policy, 4(1), 15–31.
Brown, E. (2009). Plato Ethics and Politics in The Republic. Stanford Encyclopedia of Philosophy.
Bykvist, K. (2007). The benefits of coming into existence. Philosophical Studies, 135(3), 335–362.
Cerutti, F. (2010). Defining risk, motivating responsibility and rethinking global warming. Science and Engineering Ethics, 16, 489–499.
Fahlquist, J. (2009). Moral responsibility for environmental problems – individual or institutional? Journal of Agriculture and Environment Ethics, 22, 109–124.
Fehr, E., & Fishbacher, U. (2003). The nature of human altruism. Nature, 425, 785–791.
Gardiner, S. M. (2011). A perfect moral storm – the ethical tragedy of climate change. Oxford: Oxford University Press.
Global Humanitarian Forum. (2009). The Anatomy of a Silent Crisis. Geneva: Global Humanitarian Forum.
Glover, J. (1990). Causing death and saving lives. London: Penguin.
Gosseries, A. (2008). On future generations’ future rights. The Journal of Political Philosophy, 16(4), 446–474.
Hare, R. M. (1975). Abortion and the golden rule. Philosophy & Public Affairs, 4(3), 201–222.
Hare, R. M. (1993). Essays on bioethics. Oxford: Oxford University Press.
Harman, E. (2004). Can we harm and benefit in creating? Philosophical Perspectives, 18, 89–113.
Haydar, B. (2002). Forced supererogation and deontological restrictions. The Journal of Value Inquiry, 36, 445–454.
Heyd, D. (1982). Supererogation. Cambridge: Cambridge University Press.
Heyd, D. (2011). Supererogation. Stanford Encyclopedia of Philosophy.
Hobbes, T. (1996) [1651]. Leviathan, Ed. R. Tuck. Cambridge: Cambridge University Press
Huemer, M. (2008). In defence of repugnance. Mind, 468, 899–933.
Jamieson, D. (1992). Ethics, public policy and global warming. Science, Technology & Human Values, 17(2), 139–153.
Kamm, F. (1993). Morality, mortality – volume I. New York: Oxford University Press.
Kavdal, Ø. forthcoming. The estimation of fertility effects on happiness: Even more difficult than usually acknowledged. European Journal of Population.
Keller, S. (2006). Theories of filial duty. The Philosophical Quarterly, 56(223), 254–274.
Kott, J. Eating of the Gods. (1987). Evanston: Northwestern University Press.
LaFollette, H. (1980). Licensing parents. Philosophy & Public Affairs, 9(2), 183–197.
Lenman, J. (2002). On becoming extinct. Pacific Philosophical Quarterly, 83, 253–269.
Leslie, J. (1970). The theory that the world exists because it should. American Philosophical Quarterly, 7(4), 286–298.
Leslie, J. (1972). Ethically required existence. American Philosophical Quarterly, 9(3), 215–224.
Leslie, J. (1978). Efforts to explain all existence. Mind, 346, 181–194.
Leslie, J. (1989). The need to generate happy people. Philosophia, 19(1), 29–33. doi:10.1007/BF02380090.
Leslie, J. (1996). The end of the world – the science and ethics of human extinction. London: Routledge.
Liberto, H. R. (2012). Denying the suberogatory. Philosophia, 40, 395–402. doi:10.1007/s11406-011-9343-4.
Lotz, M. (2009). Procreative reasons-relevance: On the moral significance of why we have children. Bioethics, 23(5), 291–299.
Mabbott, J. D. (1937). Is Plato’s Republic Utilitarian? Mind, 46, 386–393.
McCabe, M. M. (2005). Out of the Labyrinth: Plato’s attack on consequentialism. In C. Gill (Ed.), Virtue, Norms, and Objectivity (pp. 189–214). New York: Oxford University Press.
McMahan, J. (2013). Causing people to exist and saving people’s lives. The Journal of Ethics, 17, 5–35.
Millum, J. (2008). How do we acquire parental responsibilities? Social Theory and Practice, 34(1), 71–93.
Morgan, P. S., & Berkowitz King, R. (2001). Why have children in the 21st century? biological predisposition, social coercion, rational choice. European Journal of Population, 17, 3–20.
Nagel, T. (1979). Mortal questions. Cambridge: Cambridge University Press.
Narveson, I. (1967). Utilitarianism and new generations. Mind, 301, 62–72.
Norcross, A. (2008). Two dogmas of deontology: aggregation, rights, and the separateness of persons. Social Philosophy & Policy, 26(1), 76–95.
Parfit, D. (1987). Reasons and Persons. Oxford: Oxford University Press.
Rachels, S. (1998). Is it good to make happy people? Bioethics, 12(2), 93–110.
Reichlin, M. (1997). The argument from potential: a reappraisal. Bioethics, 11(1), 1–23.
Sinnott-Armstrong, W. (2005). It’s not my fault: Global warming and individual moral obligations. In R. B. Howarth (Ed.), Perspectives on climate change – science, economics, politics, ethics (pp. 285–307). Amsterdam: Elsevier.
Smart, R. N. (1958). Negative utilitarianism. Mind, 268, 542–543.
Vellentyne, P., & Against Maximizing Act Consequentialism. (2006). In J. Dreier (Ed.), Contemporary debates in moral theory (pp. 21–37). Oxford: Blackwell.
Wagner, P. (2012). Modernity – understanding the present. Cambridge: Polity Press.
Wellman, C. H. (1999). Gratitude as a virtue. Pacific Philosophical Quarterly, 80, 284–300.
Williams, B. (1973). A critique of utilitarianism. In J. J. Smart & W. Bernard (Eds.), Utilitarianism: for and against (pp. 77–150). Cambridge: Cambridge University Press.
Wolf, S. (1982). Moral saints. The Journal of Philosophy, 79(8), 419–439.
Woodward, J. (1986). The non-identity problem. Ethics, 96(4), 804–831.
Woodward, J. (1987). Reply to parfit. Ethics, 97(4), 800–816.
Woollard, F. (2012). Have we solved the non-identity problem? Ethical Theory & Moral Practice, 15, 677–690.
Zaitchik, A. (1982). Hobbes’s reply to the fool: The problem of consent and obligation. Political Theory, 10(2), 245–266.
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Palazzi, F. Would Human Extinction Be Morally Wrong?. Philosophia 42, 1063–1084 (2014). https://doi.org/10.1007/s11406-014-9553-7
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DOI: https://doi.org/10.1007/s11406-014-9553-7