Recent developments in biogerontology—the study of the biology of ageing—suggest that it may eventually be possible to intervene in the human ageing process. This, in turn, offers the prospect of significantly postponing the onset of age-related diseases. The biogerontological project, however, has met with strong resistance, especially by deontologists. They consider the act of intervening in the ageing process impermissible on the grounds that it would (most probably) bring about an extended maximum lifespan—a state of affairs that they deem (...) intrinsically bad. In a bid to convince their deontological opponents of the permissibility of this act, proponents of biogerontology invoke an argument which is grounded in the doctrine of double effect. Surprisingly, their argument, which we refer to as the ‘double effect argument’, has gone unnoticed. This article exposes and critically evaluates this ‘double effect argument’. To this end, we first review a series of excerpts from the ethical debate on biogerontology in order to substantiate the presence of double effect reasoning. Next, we attempt to determine the role that the ‘double effect argument’ is meant to fulfil within this debate. Finally, we assess whether the act of intervening in ageing actually can be justified using double effect reasoning. (shrink)

Dietary restriction (DR) is the most consistent environmental manipulation to extend lifespan. Originally thought to be caused by a reduction in caloric intake, recent evidence suggests that macronutrient intake underpins the effect of DR. The prevailing evolutionary explanations for the DR response are conceptualized under the caloric restriction paradigm, necessitating reconsideration of how or whether these evolutionary explanations fit this macronutrient perspective. In the authors’ opinion, none of the current evolutionary explanations of DR adequately explain the intricacies of observed (...) results; instead a context‐dependent combination of these theories is suggested which is likely to reflect reality. In reviewing the field, it is proposed that the ability to track the destination of different macronutrients within the body will be key to establishing the relative roles of the competing theories. Understanding the evolution of the DR response and its ecological relevance is critical to understanding variation in DR responses and their relevance outside laboratory environments. (shrink)

Problems of distributive justice throughout the lifespan are not new. Yet, the increased aging rate of contemporary societies and an array of new life‐extending technologies (LETs) make these problems more and more urgent and complicated. This chapter analyzes the moral and political impact of the LET. There are three kinds of “intergenerational” justice: justice between non‐coexisting generations, justice between partially co‐existing generations, and justice between coexisting generations. The advantage of considering LETs in the light of justice between age groups (...) is that we can assume a complete‐life view. LETs significantly modify the duration and the features of each stage of life. A consideration of the specific needs and features of each stage of life in a lifespan‐enhanced society is needed to regulate policies and offer fair equality of opportunity to each age group. (shrink)

The paper is mainly concerned with the problem of whether the question of extension of lifespan may be included in the constitutional essentials of a well ordered society; either as a right that must be protected, or as a prohibition. More precisely, when put in the terms of a possible prohibition, the question is about whether there are reasons that may be endorsed in the basic legislative institutions of a society, as a matter of the constitutional essentials of (...) a state, as a ground for the prohibition of research or technological practice, with the aim of sensibly extending human lifespan. It may appear as obvious that, if the answer to this question is not positive, freedom to engage in these activities immediately follows. However, this is not true. Even if there is no possibility to establish a prohibition at the level of constitutional essentials, it may still be possible to legislate at lower levels for a prohibition. As a consequence, there is another problem, i.e. the question of whether we may establish, as a matter of constitutional essentials, the right to develop research , and make use of technological resources, with the aim of sensibly extending human lifespan. Two kinds of arguments are analysed. The one saying that extension of lifespan is damaging, because it threats human nature; and the one saying that extension of lifespan is not helpful, because it leads to a life of boredom and tediousness. (shrink)

There is growing public interest in developing biomedical technologies capable of extending the human lifespan. This chapter discusses the desirability of a substantial life extension with regard to its implications for personal identity over time. The possibility of significant lifespan extension involves two different personal‐identity questions. First, it raises the question of whether one is identifiable as the very same person throughout a lifetime; secondly, it challenges our self‐conception. The chapter describes the way in which personal (...) identity as “sameness” might be affected by the prospect of substantial life extension. It then focuses on the significance of the conception of personal identity as “selfhood” for radically extended lifespans. Finally, the chapter argues that a substantial life extension raises important concerns about the continuity of one's identity over time and is not straightforwardly desirable for the individual. (shrink)

Any inquiry into the meaning and implications of the prolongation of the human lifespan requires an investigation of its metaphysical basis and its ethical outcomes. This chapter explains a series of metaphysical and ethical claims about lifespan extension. It highlights a number of arguments that are typically put forward against these claims, and shows the ways in which they are mistaken. Two such claims given in the chapter are: (1) aging and life stages are neither wholly constituted (...) by biological givens, nor wholly understandable in terms of biological parameters; instead, aging and life stages are, in crucial ways, socially constructed; and (2) death is bad, and other things being equal, a longer life is a better life. (shrink)

On the ethics of extending human life: healthy people have a right to carry on livingHumanity has long demonstrated a paradoxical ambivalence concerning the extension of a healthy human lifespan. Modest health extension has been universally sought, whereas extreme health extension has been regarded as a snare and delusion—a dream beyond all others at first blush, but actually something we are better off without. The prevailing pace of biotechnological progress is bringing ever closer the day when (...) humanity will be able to act on the latter view by rejecting a clear and present opportunity for much longer healthy lives. Indeed, some biogerontologists contend that that day has already arrived, to the extent that our hesitation in embarking on a vigorous “war on ageing” is already delaying the point at which a cure for ageing will be developed. Here I consider whether our present caution concerning the wisdom of truly curing ageing is likely to survive the increased scrutiny that it will receive in coming years as a result of these technical advances. I conclude that it will not, because of its irreconcilability with values that are more deeply held by the large majority of humanity than any values that argue against the quest for a cure. I further conclude that all the major current reasons given for not curing ageing are mere crutches to help us cope with the immutability of ageing that we have been brought up to accept. Our failure to set aside such irrationality is already shortening potential longevity—quite probably of those already alive today—to a staggering degree. Once we realise this, our determination to consign human ageing to history will be second …. (shrink)

The worst possible way to resolve this issue is to leave it up to individual choice. There is no known social good coming from the conquest of death (Bailey, 1999). - Daniel Callahan Dramatically extending the human lifespan seems increasingly possible. Many bioethicists object that life-extension will have Malthusian consequences as new Methuselahs accumulate, generation by generation. I argue for a Life-Years Response to the Malthusian Objection. If even a minority of each generation chooses life-extension, denying it (...) to them deprives them of many years of extra life, and their total extra life-years are likely to exceed the total life-years of a majority who do not want life-extension. This is a greater harm to those who want extended life than the Malthusian harms to those who refuse extended life, both because losing an extra year of life is worse than enduring a year of Malthusian conditions, and because the would-be Methuselahs have more life-years at stake. Therefore, even if life-extension seems likely to cause severe overcrowding and resource shortages, that threat is not sufficient to justify society in restricting the development or availability of life-extension. (shrink)

Abstract Objections to life extension often focus on its effects for individual well-being. Prominent amongst these concerns is the possibility that life extending technologies will extend lifespan without preventing the ageing of the mind. Writers on the subject express the fear that life extending drugs will keep us physically youthful whilst our minds decay, succumbing to dementia, boredom, and loneliness. Generally these fears remain speculative, in part due to the absence of genuine life extending technologies. In this paper, (...) however, I examine the implications of an existing life extension technology. Caloric restriction (CR) and drugs that mimic its effects, such as rapamycin, metformin and resveratrol have been shown to increase average and maximum lifespan in a wide variety of organisms, and seem likely to do so in humans. Moreover, some CR mimetic drugs (CRMs) are already widely used. This means that they present a pressing test case for fears about mental ageing in an extended life. Misgivings about mental ageing can be divided into biomedical factors such as the likelihood of brain ageing, and psychological factors such as loss of meaning and boredom. I argue that studies of CR suggest that brain ageing will be beneficially slowed. However, it is less clear that deleterious aspects of psychological ageing can be similarly retarded. I argue that this reduces the desirability of life extension unless major social changes can be made. (shrink)

Scientists, bioethicists, and policy makers are currently engaged in a contentious debate about the scientific prospects and morality of efforts to increase human longevity. Some demographers and geneticists suggest that there is little reason to think that it will be possible to significantly extend the human lifespan. Other biodemographers and geneticists argue that there might well be increases in both life expectancy and lifespan. Bioethicists and policy makers are currently addressing many of the ethical, social, and economic issues (...) raised by life extension research. However, the emphasis on philosophical argument supporting or condemning efforts to increase human longevity means that much less attention is currently being given to the factors that might play a role in generating interest in efforts to increase human longevity. This analysis considers three factors that might play a role in heightening public interest in efforts to develop biomedical technologies capable of retarding or reversing aging processes. While discussions of life extension research can seem quite futuristic and impractical, there are some powerful existential factors that might well generate considerable public support for life extension strategies if effective biomedical interventions emerge. Rather than providing philosophical justifications supporting or condemning efforts to increase human longevity, this essay seeks to promote a better understanding of the factors generating contemporary interest in prolonging life and postponing death. (shrink)

Populations in developed societies are rapidly aging: fertility rates are at all-time lows while life expectancy creeps ever higher. This is triggering a social crisis in which shrinking youth populations are required to pay for the care and retirements of an aging majority. Some people argue that by investing in the right kinds of lifespan extension technology – the kind that extends the healthy and productive phases of life – we can avoid this crisis (thereby securing a ‘longevity (...) dividend’). This chapter argues that this longevity dividend is unlikely to be paid if lifespan extension coincides with rampant technological unemployment. This does not mean that we should not pursue lifespan extension, but it does mean that the argument in its favor needs to rest on other grounds. After articulating these grounds, the chapter proceeds to consider the implications this has for our vision of the extended life, postwork utopia. It argues that this vision may need to be reconceived and suggests that one plausible reconception involves prioritizing the role of games in the well-lived life. (shrink)

Future technology may dramatically extend the human lifespan. Peter Singer argues that we should reject life extension because developing it would result in a world with lower total and average happiness. Singer’s argument depends on the claim that we should maximise average happiness per moment. I will argue that developing the life-extending drug would not be impermissible because doing so will maximise average happiness per person. I offer an independent argument for why we should adopt a consequentialist principle (...) which says to maximise average happiness per person. (shrink)

Discussions of life extension ethics have focused mainly on whether an extended life would be desirable to have, and on the social consequences of widely available life extension. I want to explore a different range of issues: four ways in which the advent of life extension will change our relationship with death, not only for those who live extended lives, but also for those who cannot or choose not to. Although I believe that, on balance, the reasons (...) in favor of developing life extension outweigh the reasons against doing so, most of these changes probably count as reasons against doing so. First, the advent of life extension will alter the human condition for those who live extended lives, and not merely by postponing death. Second, it will make death worse for those who lack access to life extension, even if those people live just as long as they do now. Third, for those who have access to life extension but prefer to live a normal lifespan because they think that has advantages, the advent of life extension will somewhat reduce some of those advantages, even if they never use life extension. Fourth, refusing life extension turns out to be a form of suicide, and this will force those who have access to life extension but turn it down to choose between an extended life they don't want and a form of suicide they may consider immoral. (shrink)

Multiple self approaches purport that to have equal concern about all stages of one’s life is not a requirement of rationality. This poses a challenge to the prudential lifespan account which Norman Daniels advocates in Just health: meeting health needs fairly. Daniels has criticised the multiple self approach in earlier works, most extensively in Am I my parents keeper? In Just health, he only takes up the issue except in one footnote, presumably because he is convinced that his preceding (...) discussions settled the matter. This article argues that Daniels underestimates the force of the multiple self objection to prudential lifespan account. (shrink)

Recent biotechnological advances pose topical challenges to Christian ethics. One such development is the attempt to try and enhance human beings and what it means to be human, also through radical life extension. In this contribution I am especially interested in limited human lifespan and attempts to radically prolong it. Although there are a number of ethical issues raised by critics, one of the most profound ethical and theological issues raised by these efforts is the question of equity (...) and justice. This artice looks at questions such as whether this biotechnology could exacerbate existing social divisions. Who will be experimented on in the development of this technology, as well as who will have access to it and be able to afford it, should it become commercially available? Being created in God’s image is a relational concept, referring not only to humanity’s relationship with God, but also with each other. Disrupting these relationships through the possible enlarging socioeconomic divisions between people through the utilisation of enhancement technology is a serious bioethical and theological question. (shrink)

Many opinions and ideas about aging exist. Biological theories have taken hold of the popular and scientific imagination as potential answers to a “cure” for aging. However, it is not clear what exactly is being cured or whether aging could be classified as a disease. Some scientists are convinced that aging will be biologically alterable and that the human lifespan will be vastly extendable. Other investigators believe that aging is an elusive target that may only be “statistically” manipulatable through (...) a better understanding of the operational principles of systems situated within complex environments. Not only is there confusion over definitions but also as to the safety of any potential intervention. Curing cell death, for example, may lead to cell cancer. The search for a cure for aging is not a clearly beneficial endeavour. This paper will first, describe contemporary ideas about aging processes and second, describe several current life extension technologies. Third, it analyses these theories and technologies, focusing on two representative and differing scientific points of view. The paper also considers the public health dilemma that arises from life extension research and examines two issues, risk/benefit ratio and informed consent, that are key to developing ethical guidelines for life extension technologies. (shrink)

The value of extending the human lifespan remains a key philosophical debate in bioethics. In building a case against the extension of the species-typical human life, Nicolas Agar considers the prospect of transforming human beings near the end of their lives into Galapagos tortoises, which would then live on decades longer. A central question at stake in this transformation is the persistence of human consciousness as a condition of the value of the transformation. Agar entertains the idea that (...) consciousness could persist in some measure, but he thinks little is to be gained from the transformation because the experiences available to tortoises pale in comparison to those available to human beings. Moreover, he thinks persisting human consciousness and values would degrade over time, being remade by tortoise needs and environment. The value available in the transformation would not, then, make the additional years of life desirable. Agar’s account does not, however, dispose of the tortoise transformation as a defensible preference. Some people might still want this kind of transformation for symbolic reasons, but it would probably be better that no human consciousness persist, since that consciousness would be inexpressible as such. Even so, it is not irrational to prefer various kinds of lifespan extension even if they involve significant modifications to human consciousness and values. (shrink)

In Humanity’s End: Why We Should Reject Radical Enhancement, Nicholas Agar presents a novel argument against the prospect of radical life-extension. Agar’s argument hinges on the claim that extended lifespans will result in people’s lives being dominated by the fear of death. Here we examine this claim and the surrounding issues in Agar’s discussion. We argue, firstly, that Agar’s view rests on empirically dubious assumptions about human rationality and attitudes to risk, and secondly, that even if those assumptions are (...) granted, the fears that Agar adverts to are unlikely to dominate people’s lives if and when radical life-extension is made possible. Further, we claim that the structure of the decision-making process around life-extension is unlikely to be the way that it would have to be in order for Agar’s claims about fear of death to make sense. Finally, we argue that Agar is implicitly committed to a narrow conception of human value. In response, we suggest that the pursuit of life-extension can itself be seen as an expression of certain important aspects of our distinctively human nature. (shrink)

Anything within the causal economy of the universe is entirely natural, including values, humans themselves, together with their artifacts and products, and lifespans either as presently the case, or else radically extended. Further, normality of itself is no predicator of normativity. In view of this, arguments concerning the appropriate length of life from naturalness or normalness, are akin to the kind of hardened prejudice manifested by Procrustes in his beliefs concerning the appropriate length of beds, and the sleepers therein. Various (...) modern commentators have taken up the suggestion, initiated in the discourse by Williams, using the example of Karel Capek's opera The Makropulos Secret, that we should not seek to extend life because it will end in boredom. For a person‐process that has achieved self‐resolution, and come to a processual end, for a true Makropulos, there would be no passion, no fear, no affect, no boredom, no disvalue, no wailing. (shrink)

One of the strongest objections to the development and use of substantially life-extending interventions is that they would exacerbate existing unjust disparities of healthy lifespans between rich and poor members of society. In both popular opinion and ethical theory, this consequence is sometimes thought to justify a ban on life-prolonging technologies. However, the practical and ethical drawbacks of banning receive little attention, and the viability of alternative policies is seldom considered. Moreover, where ethicists do propose alternatives, there is scant effort (...) to consider their merits in light of developing world priorities. In response to these shortcomings, I distinguish four policy options and, on the basis of a plausible intuition about fairness, evaluate their implications for a fair distribution of healthy lifespans. I claim that even in developing nations it would be fairest to favor policies that promote equal access to at least one promising category of substantially life-extending intervention: calorie restriction mimetics. (shrink)

Projects of radical life extension have been discussed amongst scientists for years. Some bioethicists express reservations about this endeavor. A common objection appeals to demography: if the human lifespan is dramatically expanded, humanity would face an overpopulation problem. In this essay, the authors reply to this objection. They posit that radical life extension is unlikely to lead to overpopulation because overpopulation is determined more by fertility rates than by longevity, and as a result of the advanced phases (...) of industrialization, fertility rates are likely to be reduced, and therefore, population size would become stable. However, they argue that although overpopulation is not a concern for the foreseeable future, it is still important to acknowledge its potential harms. Finally, they argue that even if overpopulation becomes a problem caused by radical life extension, there are plausible ways to solve it. (shrink)

The biosphere represents the global sum of all ecosystems. According to a prominent view in environmental ethics, ecocentrism, these ecosystems matter for their own sake, and not only because they contribute to human ends. As such, some ecocentrists are critical of the modern industrial civilization, and a few even argue that an irreversible collapse of the modern industrial civilization would be a good thing. However, taking a longer view and considering the eventual destruction of the biosphere by astronomical processes, we (...) argue that humans, a species with considerable technological know-how and industrial capacity could intervene to extend the lifespan of Earth’s biosphere, perhaps by several billion years. We argue that human civilization, despite its flaws and harmful impacts on many ecosystems, is the biosphere’s best hope of avoiding premature destruction. We argue that proponents of ecocentrism, even those who wholly disregard anthropocentric values, have a strong moral reason preserve the modern industrial civilization, for as long as needed to ensure biosphere survival. (shrink)

Background: Recent studies on public attitudes toward life extension technologies show a mix of ambivalence toward and support for extending the human lifespan. Attitudes toward genetic modification of organisms and technological enhancements may be used to categorize individuals according to political or ideological orientation such as technoprogressive or conservative and it could be easy to assume that these categories are related to more general categorizations related to culture, e.g. between Traditional and Secular-rational values in the World Values Survey. (...) This paper discusses how attitudes toward aspects of radical life extension may be related to cultural values as revealed in an online deliberative survey among university students conducted between January 2012 to January 2013. Survey results suggest that attitudes toward radical life extension tend to be mixed among groups categorized as Traditional, Secular-rational, Survivalist, and Self-expressionist. The study explored the relation between responses of 326 university students to 5 key questions on radical life extension and the cultural values they tend to favor as indicated by their response to 20 statements from the World Values Survey.Design and Method: The survey consisted of 3 stages: an online pre-discussion survey, face-to-face discussion, and post-discussion survey. After completing the 5 main survey questions in stage 1, participants were presented two additional questionnaires: one on cultural attitudes using 20 statements from the 2004-2008 World Values Survey and another on health attitudes with 12 statements from Dutta-Bergman’s 2004 study. In stage 2, participants were engaged in a face-to-face discussion in class focusing on their responses to the five key questions. After the discussion, they were invited to reconsider the choices and reasons they posted in stage 1 in the light of the face-to-face class discussion in stage 2.Results: Responses to the five survey questions showed that there tended to be more individuals across groups who disagreed with adopting technologies that radically extend the human lifespan beyond the current limit of 120 years. Attitudes toward radical life extension did not correspond to cultural attitudes indicated by responses to the WVS questions. The proportion of agreement/disagreement to statements presented in each of the five questions varied across cultural groups and there tended to be more individuals who disagreed with radical life extension in all groups. Changes in responses after the discussion stage were not significant and most respondents maintained their prior views.Discussion: Cultural attitudes associated with familiar technologies may not correspond with attitudes toward newer technologies since beliefs and values may need to be adapted to new imagined situations that the new technologies elicit. Moral understandings associated with familiar technological habits and beliefs are not necessarily carried over to new technologies. (shrink)

A decline in public sector extension services in developing countries has led to an increasing emphasis on alternative extension approaches that are participatory, demand-driven, client-oriented, and farmer centered. One such approach is the volunteer farmer-trainer approach, a form of farmer-to-farmer extension where VFTs host demonstration plots and share information on improved agricultural practices within their community. VFTs are trained by extension staff and they in turn train other farmers. A study was conducted to understand the rationale (...) behind the decisions of smallholder farmers to volunteer their time and resources to train other farmers without pay and to continue volunteering. Data were gathered through focus group discussions and individual interviews involving 99 VFTs. Findings of the study showed that VFTs were motivated by a combination of personal and community interests that were influenced by religious beliefs, cultural norms, and social and economic incentives. Altruism, gaining knowledge and skills, and social benefits were the most frequently mentioned motivating factors for becoming VFTs.3 years after starting, the income earned from selling associated inputs and services was also a main motivating factor. There were no significant differences between motivating factors for men and women VFTs. The findings point to the fact that VFTs work effectively without being paid, but investments in human, social, and financial capital are crucial to keeping them motivated. These factors are key to ensuring the sustainability of farmer-to-farmer extension programs beyond the projects’ lifespan. (shrink)

Dietary restriction (DR) famously extends lifespan and reduces fecundity across a diverse range of species. A prominent hypothesis suggests that these life‐history responses evolved as a survival‐enhancing strategy whereby resources are redirected from reproduction to somatic maintenance, enabling organisms to weather periods of resource scarcity. We argue that this hypothesis is inconsistent with recent evidence and at odds with the ecology of natural populations. We consider a wealth of molecular, medical, and evolutionary research, and conclude that the lifespan (...) extension effect of DR is likely to be a laboratory artifact: in contrast with captivity, most animals living in natural environments may fail to achieve lifespan extension under DR. What, then, is the evolutionary significance of the suite of responses that extend lifespan in the laboratory? We suggest that these responses represent a highly conserved nutrient recycling mechanism that enables organisms to maximize immediate reproductive output under conditions of resource scarcity. (shrink)

This chapter focuses on documenting the changes in life expectancy and human lifespan and reviewing current understandings of demographic and epidemiological transitions. It allows assumption of shared understandings of the meaning of human aging and old age. A key policy indicator of changes in health and life expectancy is the concept of healthy active life expectancy and associated concept of disability‐free life expectancy. From a social gerontological perspective, aging is a concept that is less contested than the idea of (...) old age. The biomedicalization of aging has been a major influence across social spaces. Vincent has described four categories of anti‐aging medicine: symptom alleviation; life expectancy extension; lifespan extension; and abolition. The development of anti‐aging technology, science, and practice challenges us to think about the enhancement of human aging and the future of later life. Attitudes to aging remain essentially negative with little evidence to suggest that institutionalized ageism will disappear. (shrink)

Fused, elongated mitochondria are more efficient in generating ATP than fragmented mitochondria. In diverse C. elegans longevity pathways, increased levels of fused mitochondria are associated with lifespan extension. Blocking mitochondrial fusion in these animals abolishes their extended longevity. The long‐lived C. elegans vhl‐1 mutant is an exception that does not have increased fused mitochondria, and is not dependent on fusion for longevity. Loss of mammalian VHL upregulates alternate energy generating pathways. This suggests that mitochondrial fusion facilitates longevity in (...) C. elegans by increasing energy metabolism. In diverse animals, ATP levels broadly decreases with age. Substantial evidence supports the theory that increasing or maintaining energy metabolism promotes the survival of older animals. Increased ATP levels in older animals allow energy‐intensive repair and homeostatic mechanisms such as proteostasis that act to prevent cellular aging. These observations support the emerging paradigm that maintaining energy metabolism promotes the survival of older animals. (shrink)

The value of extending the human lifespan remains a key philosophical debate in bioethics. In building a case against the extension of the species-typical human life, Nicolas Agar considers the prospect of transforming human beings near the end of their lives into Galapagos tortoises, which would then live on decades longer. A central question at stake in this transformation is the persistence of human consciousness as a condition of the value of the transformation. Agar entertains the idea that (...) consciousness could persist in some measure, but he thinks little is to be gained from the transformation because the experiences available to tortoises pale in comparison to those available to human beings. Moreover, he thinks persisting human consciousness and values would degrade over time, being remade by tortoise needs and environment. The value available in the transformation would not, then, make the additional years of life desirable. Agar’s account does not, however, dispose of the tortoise transformation as a defensible preference. Some people might still want this kind of transformation for symbolic reasons, but it would probably be better that no continuing human consciousness persist, since that consciousness would be inexpressible as such. Even so, it is not irrational to prefer various kinds of lifespan extension even if they involve significant modifications to human consciousness and values. (shrink)

Ageing is a complex phenomenon which remains a major challenge to modern biology. Although the evolutionary biology of ageing is well understood, the mechanisms that limit lifespan are unknown. The isolation and analysis of single‐gene mutations which extend lifespan (Age mutations) is likely to reveal processes which influence ageing. Caenorhabditis elegans is the only metazoan in which Age mutations have been identified. The Age mutations not only prolong life, but also confer a complex array of other phenotypes. Some (...) of these phenotypes provide clues to the evolutionary origins of these genes while others allude to mechanisms of lifespan‐extension. Many of the Age genes interact and share a second common phenotype, that of stress resistance. Rather than invertebrate ageing being determined by a ‘clock mechanism’, a picture is emerging of ageing as a non‐adaptive process determined, in part, by resistance to intrinsic stress mediated by stress‐response genes. (shrink)

The hypothesis that foreseeable developments in interventions directed to forestall and to treat the disabilities of aging might result in the extension of the human lifespan may be further supported by the “evolutionary theory of aging.” Besides caloric restriction, several hormone supply or replacement strategies are considered to contrast the functional decline associated with aging. Hormone treatments may include growth hormone (GH), insulin‐like growth factor I (IGF‐I) signaling, dehydroepiandrosterone (DHEA), melatonin, testosterone, progesterone, and estrogen. In the 1990s, DHEA (...) was exalted as a possible candidate for the “fountain of youth.” Several experiments on animals have shown that DHEA is a multifunctional adrenal steroid with immune function enhancement, anti‐diabetic, anti‐cancer, and anti‐aging effects. The ethical questions concerning the extension of the lifespan belong to two distinct areas: the area of individual morality and the area of social morality. (shrink)

Biological studies have demonstrated that it is possible to slow the ageing process and extend lifespan in a wide variety of organisms, perhaps including humans. Making use of the findings of these studies, this article examines two problems concerning the effect of life extension on population size and welfare. The first—the problem of overpopulation—is that as a result of life extension too many people will co-exist at the same time, resulting in decreases in average welfare. The second—the (...) problem of underpopulation—is that life extension will result in too few people existing across time, resulting in decreases in total welfare. I argue that overpopulation is highly unlikely to result from technologies that slow ageing. Moreover, I claim that the problem of underpopulation relies on claims about life extension that are false in the case of life extension by slowed ageing. The upshot of these arguments is that the population problems discussed provide scant reason to oppose life extension by slowed ageing. (shrink)

Wenn eine Person unter einer tödlichen Krankheit leidet und nicht über die Ressourcen für eine medizinische Behandlung verfügt, sind wir normalerweise dazu verpflichtet, ihr die notwendigen Ressourcen bereitzustellen. Wären wir aber in einem biotechnischen Zukunftsszenario, in dem die menschliche Lebensspanne durch Eingriffe in den Alterungsprozess erhöht werden kann, auch dazu verpflichtet, anderen Personen die notwendigen Ressourcen für solche Maßnahmen bereitzustellen? John Harris hat argumentiert, dass wir zu solch einer direkten biotechnischen Lebensverlängerung verpflichtet wären, da ein Leben zu verlängern das Gleiche (...) sei, wie ein Leben zu retten. Im vorliegenden Aufsatz wird gezeigt, dass Harris’ Argument nicht schlüssig ist, da entgegen seiner Prämisse ein begrifflicher Unterschied zwischen der Rettung und der Verlängerung eines Lebens besteht. Auf Grundlage von Harris’ zurückgewiesenem Argument werden dann aber zwei alternative Argumente für eine (prima facie) Pflicht zur direkten Lebensverlängerung konstruiert. Das erste Argument basiert auf der Überlegung, dass durch eine direkte biotechnische Lebensverlängerung trotz des begrifflichen Unterschieds mit einer substanziellen Wahrscheinlichkeit Leben gerettet werden würden. Das zweite Argument besagt, dass trotz deskriptiver Unterschiede eine moralische Äquivalenz zwischen der Rettung und der Verlängerung eines Lebens besteht, sofern durch die bloße Lebensverlängerung das Leben um die gleiche Dauer und Qualität verlängert wird wie durch die Lebensrettung. ---------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------- When a person suffers from a deadly disease and is lacking the resources for a medical treatment, we are normally obliged to provide the necessary resources. But would we also be morally obliged to provide the resources for an extension of someone’s lifespan through anti-aging treatments which might be developed due to biotechnological progress? John Harris has argued that there would be an obligation to such a direct biotechnical life extension because extending a life is the same as saving a life. In the present paper, it will be shown that Harris’ argument is not sound since, contrary to his premise, there is a conceptual difference between extending and saving a life. On the basis of Harris’ rejected argument, though, two alternative arguments for a (prima facie) obligation to direct biotechnical life extension will be developed. The first argument is based on the idea that, despite the conceptual difference, one saves someone’s life with a substantial probability when extending it by direct biotechnical means. In the second argument, it will be argued that there is a moral equivalence between extending and saving someone’s life despite the descriptive differences as far as the additional lifetime has the same duration and quality in both cases. (shrink)

With the ever‐increasing lifespan along with societal changes, women can marry and procreate later than in previous centuries. However, pathogenic genetic variants segregating in the population can lead to female subfertility or infertility well before the average age of normal menopause, leading to counter‐selection of such deleterious alleles. In reviewing this field, we speculate that a logical consequence would be the later occurrence of menopause and the extension of women's reproductive lifespan. We illustrate this point with a (...) simple model that applies to other variants that contribute to female infertility, including epigenetic variation. We also consider the effect of medical interventions and lifestyle. (shrink)

Using philosophical guidelines--and applying these guidelines throughout a patient's lifespan--this text assists readers in making ethically sound choices in nursing. It explores both traditional and contemporary ethical theories and acknowledges changing trends in the health field, incorporating issues such as managed care. Includes clinical case studies within each chapter. Incorporates a new organization in Part Two, in three sections entitled "Developmental Highlights," "Issues and Problems," and "Morally Reasoned Nursing Interventions." Provides new "What if?" questions throughout to help apply theory (...) to real events. Offers extensive analysis of euthanasia and assisted suicide. Includes thorough coverage of the HIV/AIDS epidemic and its moral complexities. Discusses organ transplantation and experimental medical treatments in ethical context. Ideal for practicing nurses looking for a reference on professional ethics. (shrink)

Drawing on Ezekiel Emanuel’s controversial piece ‘Why I hope to die at 75,’ I distinguish two types of concern in ethical debates about extending the human lifespan. The first focusses on the value of living longer from prudential and social perspectives. The second type of concern, which has received less attention, focusses on the value of aiming for longer life. This distinction, which is overlooked in the ethical literature on life extension, is significant because there are features of (...) human psychology and the structure of a life that should give pause when considering how long one should aim to live, but which do not neatly coincide with considerations about how valuable additional life is likely to be. I argue that, while Emanuel’s case for hoping to die at 75 is unconvincing, he nonetheless provides weak pro tanto considerations in favour of taking a moderate life span as a prudential aim around which to base at least some significant life plans. (shrink)

More precisely, transhumanists advocate increased funding for research to radically extend healthy lifespan and favor the development of medical and technological means to improve memory, concentration, and other human capacities. Transhumanists propose that everybody should have the option to use such means to enhance various dimensions of their cognitive, emotional, and physical well-being. Not only is this a natural extension of the traditional aims of medicine and technology, but it is also a great humanitarian opportunity to genuinely improve (...) the human condition. (shrink)

Social learning is a source of behaviour for many species, but few use it as extensively as they seemingly could. In this article, I attempt to clarify our understanding of why this might be. I discuss the potential computational properties of social learning, then examine the phenomenon in nature through creating a taxonomy of the representations that might underly it. This is achieved by first producing a simplified taxonomy of the established forms of social learning, then describing the primitive capacities (...) necessary to support them, and finally considering which of these capacities we actually have evidence for. I then discuss theoretical limits on cultural evolution, which include having sufficient information transmitted to support robust representations capable of supporting variation for evolution, and the need for limiting the extent of social conformity to avoid ecological fragility. Finally, I show how these arguments can inform several key scientific questions, including the uniqueness of human culture, the long lifespans of cultural species, and the propensity of animals to seemingly have knowledge about a phenomenon well before they will act upon it. (shrink)

Social learning is a source of behaviour for many species, but few use it as extensively as they seemingly could. In this article, I attempt to clarify our understanding of why this might be. I discuss the potential computational properties of social learning, then examine the phenomenon in nature through creating a taxonomy of the representations that might underly it. This is achieved by first producing a simplified taxonomy of the established forms of social learning, then describing the primitive capacities (...) necessary to support them, and finally considering which of these capacities we actually have evidence for. I then discuss theoretical limits on cultural evolution, which include having sufficient information transmitted to support robust representations capable of supporting variation for evolution, and the need for limiting the extent of social conformity to avoid ecological fragility. Finally, I show how these arguments can inform several key scientific questions, including the uniqueness of human culture, the long lifespans of cultural species, and the propensity of animals to seemingly have knowledge about a phenomenon well before they will act upon it. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Artificial Minds and the Dilemma of Personal IdentityChristian Coseru (bio)Artificial You: AI and the Future of Your Mind. By Susan Schneider. Princeton: Princeton University Press, 2019.I. IntroductionAll diurnal organisms are stirred to action by light, but as entomologists have long known, for nocturnal insects the pull of its radiance can also spell doom. The image of a moth drawn to flame is suggestive of the sort of self-destructive behavior (...) that poets have long used to maximum rhetorical effect: "Thus had the candle singed the moth" proclaims Portia in the Merchant of Venice, pitying the fate that befell Arragon. The deceptive lure of artificial lights, however, is no longer mere fodder for the poetic imagination. Ecologists are warning us that species accustomed to navigating by moon or starlight, from beetles to seals and sea turtles, are getting confused, or worse.1 And medical science is beginning to establish a link between night-time light exposure and various sleep and metabolic disorders.2 Yet our Promethean ingenuity is a sight to behold: fueled by illumination tropes as metaphors for awareness and understanding, our mastery of light and of the electromagnetic wave spectrum has brought forth technologies, from CT scans and electromicrography to myoelectric sensors and solid-state lighting, that inspire utopian visions of genetically engineered and neurally enhanced post-humans alongside dystopian fantasies of runaway cyborgs. Among these technologies, AI stands out as the shiny new object commanding our attention.The future envisioned as a result of these technological advancements now includes the prospect of artificial minds, minds that, if they were to come anywhere close to resembling ours, let alone to surpassing human intelligence, would pose serious existential and ethical challenges for humanity. Or so the story goes, if Susan Schneider's compelling foray into AI research is any indication. Indeed, Artificial You: AI and the Future of Your Mind (Schneider 2019) offers a philosophically savvy investigation of the debates that animate much of the contemporary fascination with the prospect of machine intelligence, which by some of the more optimistic [End Page 281] measures could be achieved within the lifetime of most millennials.3 As books aimed at a general audience pondering the promises and perils of superintelligent AI go, Artificial You succeeds precisely where most others falter: it brings conceptual clarity to often vague and nebulous claims by techno optimists about the impending emergence of consciousness from computational complexity, while at the same time offering a sober reminder that the technology underlying, say, artificial neural networks is far more advanced than most AI skeptics realize.I will not address Schneider's survey of the state of the art in AI research, which is succinct, informative, and for the most part illustrative of the transhumanist ethos she appears to embrace. Instead, I will focus on the problem of personal identity and the seemingly insurmountable challenges it raises for the prospect of radical human enhancement and synthetic consciousness. Specifically, I will argue that conceptions of personal identity rooted in psychological continuity akin to those proposed by Parfit and the Buddha may not provide the sort of grounding that many transhumanists chasing the dream of life extension think that they do if they rest upon ontologies that assume an incompatibility between identity and change. I will also suggest that process ontologies that take change to be primary, such as those that align with contemporary systems biology, offer a better way out of the personal identity dilemma. But the solution in this case, which regards biological organisms as processes rather than things, may constrain the possibility of biologically inspired superintelligent aliens (BISAs), which Schneider (following Bostrom 2014) posits as possibly the most common form of (extraterrestrial) superintelligence in the universe.II. Enhancement Beyond RecognitionPerhaps the central leitmotif of transhumanism is the idea of enhancement by means of current technologies such as genetic engineering and information technology as well as future ones such as nanotechnology and artificial intelligence. The range of enhancement options includes the extension of the human lifespan, the elimination of disease, and most importantly the augmentation of human intellectual, physical, and affective capacities (Bostrom 2003b). Further down the line, enhancement may move beyond merely augmenting existing... (shrink)

Menopause is an evolutionary mystery: how could living longer with no capacity to reproduce possibly be advantageous? Several explanations have been offered for why female humans, unlike our closest primate relatives, have such an extensive post-reproductive lifespan. Proponents of the so-called “grandmother hypothesis” suggest that older women are able to increase their fitness by helping to care for their grandchildren as allomothers. This paper first distinguishes the grandmother hypothesis from several other hypotheses that attempt to explain menopause, and then (...) develops a formal model by which these hypotheses can be compared and tested by empirical researchers. The model is then modified and used to respond to a common objection to the grandmother hypothesis: that human fathers, rather than grandmothers, are better suited to be allomothers due to their physical strength and a high incentive to invest in their own children. However, fathers—unlike maternal grandmothers—can never be sure that the children they are caring for are their own. Incorporating paternity uncertainty into the model demonstrates the conditions under which the grandmother hypothesis is more plausible than a hypothesis that focuses on the contributions of men. (shrink)

As things currently stand, our deaths are unavoidable and our lifespans short. It might be thought that these qualities leave room for improvement. According to a prominent line of argument in philosophy, however, this thought is mistaken. Against the idea that a longer life would be better, it is claimed that negative psychological states, such as boredom, would be unavoidable if our lives were significantly longer. Against the idea that a deathless life would be better, it is claimed that such (...) a life would be lacking in important sources of value, because death is a precondition for many of our valuing attitudes. I argue that these problems are avoided by very long lives that incorporate fading memory, limited ignorance of future events, and temporal scarcity. I conclude that very long lives are, in principle, desirable, and that death does not play an essential role in our valuing attitudes. (shrink)

Transhumanism promises us freedom from the biological limitations inherent in our nature. It aims to enhance physical, emotional and cognitive capacities thus opening up new possibilities and horizons of experience. Since many transhumanist aspirations resemble those within the domain of religion, this paper compares Christian ethics to transhumanist ethics with respect to the body and the environment and offers a critique of transhumanism. Three areas of contention are discussed: the modification of our given human nature, the radical extension of (...) our lifespans and our relationship to the natural environment. It argues that in these three areas, the underlying values being transmitted to future generations about the body and the environment are incompatible with Christian principles. (shrink)

As things currently stand, our deaths are unavoidable and our lifespans short. It might be thought that these qualities leave room for improvement. According to a prominent line of argument in philosophy, however, this thought is mistaken. Against the idea that a longer life would be better, it is claimed that negative psychological states, such as boredom, would be unavoidable if our lives were significantly longer. Against the idea that a deathless life would be better, it is claimed that such (...) a life would be lacking in important sources of value, because death is a precondition for many of our valuing attitudes. I argue that these problems are avoided by very long lives that incorporate fading memory, limited ignorance of future events, and temporal scarcity. I conclude that very long lives are, in principle, desirable, and that death does not play an essential role in our valuing attitudes. (shrink)

What if science enabled us to live an extended lifespan? Well, not us, but people in the future, and perhaps not everybody in the future, at least not at first. Should we allow and encourage science to develop this capability, or should we try to prevent or inhibit it? John Davis's book New Methuselahs: The Ethics of Life Extension is a thorough exploration of these questions. He presents the arguments for and against developing this capacity, and he considers (...) three perspectives: those of individuals who will be able to extend their lives (the Haves), individuals who will not because they can't afford to (the Have‐nots), and individuals who will not extend their lives because they are opposed to doing so (the Will‐nots). Davis is a philosopher, and the bulk of this book is for the cognoscenti. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:In Memoriam: Eleanor V. Stubley (1960–2017)Roberta LambIt is dusk in the desert—that bewitching hour when the intensity of today’s unrelenting heat suddenly lifts with the hint of a breeze and a promise of darkness. Worn and weary with dust trailing my every movement, I am inexorably drawn forward by the distant sounds of drums and community. I am curious to see what lies ahead, but for one brief minute (...) I look back from where I have come. A single window penetrates the gloom. It opens on a small room, cluttered with mementos celebrating a long history of great artistry. I feel the weight of this history, even at this distance; but what captures my attention is the music making in the only uncluttered corner of the room where four musicians are poring over a recently discovered score of a late Beethoven string quartet. While the music making appears to be motivated and bound by the score, it is as if the musicians are searching for something that lies beyond the score. At times, the searching seems to question the shape or presence of a particular note or melodic motive; other times, it appears to be a quest for “the work,” the string quartet written by Beethoven. As I continue to eavesdrop, I am struck by the way in which the searching in both instances ultimately seems to evolve into a question of ensemble. It is as if the musicians are not only trying to discover the music implied by [End Page 203]the score notations, but also trying to find themselves, trying to get a sense of who they are in relationship to this music. It is a phenomenon that I have encountered frequently in my travels, and I wonder, as the sounds in the distance reenter my consciousness, why of all possibilities the window of my mind opened on this particular room.1Thus, Eleanor V. Stubley began a moving evocation of body, sound, and shifting identities in philosophical argument. It remains my favorite opening of any philosophical essay I have ever read, even though her skill and artistry grew immensely in the subsequent nineteen years. To be honest, the connection with this particular essay comes from my bond with Eleanor at a particular time and particular place, when each of us was establishing our career in a recognized university. We shared a lot through extensive phone calls and my visits to Montreal. While Eleanor was able to travel, we also shared conference spaces together, when I often functioned as her advocate as well as her friend. As I re-read this essay and the others, I remember fondly particular conversations where we discussed ideas and feelings about music, teaching, and life. We shared our health challenges and their effects on our lives and work. We talked about being female in the academy; she shared issues around disability; I around homophobia. I see sources in the endnotes for this essay resulting from those conversations and the ideas Eleanor worked out as we chatted. I find similar memories in her other philosophical essays. I am happy to have contributed to the thinking that came out of this heady time. We were slaying dragons!Eleanor (and I must be personal because we were friends) contributed an original and strongly philosophical base to music education within a handful of articles. She never wrote the book she intended in those earlier years. Instead, she refocused her career outside of music education, partly because she realized she had much to say, do, and create within a limited lifespan and partly because music education did not have room for such brilliance and creativity. In fact, music education gave Eleanor a not so gentle shove. She worked nearly all of the last two decades of her life in the departments of musicology and performance. In addition, she served McGill’s students as Associate Dean of Graduate Studies. She knew she had no time to slay music education’s dragons. Even so, Eleanor continued to contribute philosophical columns to the Canadian Music Educator. She wrote regularly for volumes 42–44 (2001–2003) and intermittently before and after those years. These thirteen columns... (shrink)

The study of cellular senescence and proliferative lifespan is becoming increasingly important because of the promises of autologous cell therapy, the need for model systems for tissue disease and the implication of senescent cell phenotypes in organismal disease states such as sarcopenia, diabetes and various cancers, among others. Here, we explain the concepts of proliferative cellular lifespan and cellular senescence, and we present factors that have been shown to mediate cellular lifespan positively or negatively. We review much (...) recent literature and present potential molecular mechanisms by which lifespan mediation occurs, drawing from the fields of telomere biology, metabolism, NAD+ and sirtuin biology, growth factor signaling and oxygen and antioxidants. We conclude that cellular lifespan and senescence are complex concepts that are governed by multiple independent and interdependent pathways, and that greater understanding of these pathways, their interactions and their convergence upon specific cellular phenotypes may lead to viable therapies for tissue regeneration and treatment of age‐related pathologies, which are caused by or exacerbated by senescent cells in vivo. (shrink)