LIFE

Like many of the concepts foundational to the field of bioethics, life is a subject about which there is both longstanding conviction and increasing uncertainty. The beginnings and endings of life, as well as its creation, have become subject to greater technological modification, particularly through the rise of the modern biological sciences and new reproductive and genetic technologies. In the late twentieth century, increasing technological control over the management, regulation, and production of life and lifelike systems, as well as the accelerating commodification of life forms, raise questions about the limits of what can or should be done to life itself. Hence, seemingly timeless and universal human attitudes toward life, such as mourning in the wake of its loss and joy in its creation, are today accompanied by profound ambiguities concerning the meaning, value, and definition of life.

Some commentators have claimed that even a few decades ago life was more often understood as an absolute value—for example, among medical professionals, for whom the protection of life was an unquestioned moral duty (Parsons et al.). Related arguments hold that the technologization of life has produced a shift away from an understanding of life as an absolute value, and toward more relative assessments of the quality of life (Parsons et al., pp. 405–410). The appearance of an entry entitled "Life" in an encyclopedia of bioethics would support the position that life itself has become the object of increased management in the form of decision making.

In contrast to the urgent call for guidelines concerning the subject of life is the difficulty of defining this term. Neither philosophers, theologians, nor scientists can offer a clear understanding of life. This is in part due to the wideranging uses of the term. Not only does life have many meanings as a noun, it is a key term within a wide range of systems of thought from religion to science. In all of the many senses in which the word is used, definitions of it have varied historically in relation to changing social forces and cultural values. Contemporary moral, legal, theological, and scientific uncertainty attends the origins of life, the relative importance of human versus other forms of life, the beginnings and endings of life, the creation and destruction of life, and the nature of life. These and other concerns follow from the definitional issues, raised by the concept of life itself, that remain subject to dispute and ongoing transformation.

Historical and Cultural Variations

To be animate or vital is a condition for which crossculturally and transhistorically there exists a range of modes of recognition. Broadly speaking, notions of life, or of a vital force, are often connected to beliefs about the supernatural, divinity, and sacredness. It is also generally the case that understandings of life are often made most explicit in relation to death (Bloch and Parry; Huntington and Metcalf). These features characterize both Judeo-Christian and classical understandings of life, the two predominant sources of its definition in the Euro-American tradition prior to the rise of modern science.

According to the Judeo-Christian tradition, life is interpreted and valued as a gift from God. The Old Testament relates that God created man (Adam) in his own likeness, with dominion over all living things. In the Garden of Eden, life was everlasting; and Adam and Eve's expulsion, through which they became mortal, was both a sign of divine displeasure and a partial rescinding of the gift of life. According to the New Testament, the gift of everlasting life was restored through the sacrifice of God's only begotten son, Jesus, and his resurrection to the kingdom of Heaven. Consequently, only those who believe in the resurrection of Christ have "life" in the Christian sense. When Jesus states "I am life" (or "I am the way, the truth, and the life"), it is the resurrection promised to believers in the life, death, and salvation of Christ that is invoked. The historian Barbara Duden notes:

In most of the New Testament and in two thousand years of ecclesiastical usage, to "have life" means to participate as a believing Christian in the life of Christ.… Even the dead live in Christ, and only those who live in Christ can have life in this world. Of those who exist outside this relationship, the Church has consistently spoken of those who "live" under conditions of death. (p. 102)

Blood is a key symbol of life in the Christian tradition as well as in much secular culture, most notably medicine. To give the "gift of life" is more literally possible today than ever before in the context of organ donation, whereby a body part of a deceased person may "live on" in the body of another person, or a living donor may sacrifice a body part (such as a kidney) on behalf of a relative. The capacity to donate not only blood and vital organs but also egg and sperm cells, and the increasing availability of bodily tissues through a service sector and a marketplace, complicate the understanding of life as a "gift" (Parsons et al.; Titmuss). The sacrificial importance of the body and the blood of Christ makes the exchange of body tissue a potent symbolic practice, as does the definition of kin ties in terms of "blood relations."

The association between the flow of blood and the flow of life anticipates the notion of germ plasm (the hereditary material of the germ cells) as the basis for heredity; this in turn gives rise to the modern scientific concept of the gene, which is today described as the essence of life. While the gene in some senses represents the triumph of mechanistic explanations of life itself, the most reductionist accounts of genes as "selfishly" reproducing entities defined by the attainment of their own inbuilt "ends" may seem not dissimilar from that of the most influential proponent of vitalism, Aristotle. Aristotelian definitions of life were predominant for nearly two millennia, in part because Aristotle was among the few philosophers of antiquity to pay significant attention to the problem of defining life. According to Aristotle, life is defined by the possession of a soul, or vital force, through which an entity is rendered animate and given shape. The attainment of a predetermined end point is seen as the purpose of life in Aristotelian terms, a purpose that is contained in itself, independent of any external causal agent. This view is known as entelechy—a telos, an ultimate end that is self-defined as the achievement of a final form.

Although the Aristotelian view was based on close observations of the natural world and eschewed any notion of divine creation, it is strongly criticized by modern scientists for its teleologism (conflation of an endpoint with a cause) and essentialism (predeterminism), which are dismissed as metaphysical and therefore insufficiently empirical. Cartesian accounts of animation, which defined life in terms of the organization instead of the essence of matter, succeeded Aristotelian vitalism in the seventeenth century. From the perspective of mechanism, which explained motion or aliveness purely in terms of the articulation among parts of a whole (as in the ticking of a watch), Aristotelian vitalism came to be seen as mystical, nonobservable, and therefore unscientific.

The history of the concept of life in Western science, from which many of the most authoritative contemporary definitions of it are derived, underscores the importance of change and variation in the meanings of this term (Canguilhem; Schrödinger). Eighteenth-century natural historians employed a horizontal ordering strategy to classify diverse life forms into taxonomies of kind or type. A vertical ranking of the value of these life forms (known as the great chain of being, descending from God to humanity and thence to other living entities) was based on their proximity to the divine. According to this conceptual framework, life comprised a diverse array of animate entities classified epistemologically and ranked theologically in terms of proximity to God. The sacred act of divine creation that brought life into being was, in this schema, paralleled by the secular production by natural philosophers, such as Carolus Linnaeus (1707–1778), of a classification system through which life forms were named, defined, and ordered according to their perceived nature, which was seen to be immutable.

The stability of these vertical ranking and horizontal classifying axes was irrevocably shaken by the gradual acceptance of the evolutionary model of life, in particular the work of Charles Darwin, which, over the latter half of the nineteenth century, gained acceptance in Europe and America. With the rise of Darwinian theories of evolution came a radical new understanding of life: as an underlying connectedness of all living things. It was the evolutionary view of life as a distinct object of study in its own right that gave rise to the modern notion of life itself; not until this time could such a thing have been conceived. Many of the current dilemmas in bioethics demanding our attention came to be understood as a direct result of the emergence of this particular conceptualization of life.

As the historian Michel Foucault points out, life itself did not exist before the end of the nineteenth century; it is a concept indebted to the rise of the modern biological sciences.

Historians want to write histories of biology in the nineteenth century; but they do not realise that biology did not exist then, and that the pattern of knowledge that has been familiar to us for a hundred and fifty years is not valid for a previous period. And that if biology was unknown, there was a very simple reason for it: that life itself did not exist. All that existed was living beings, which were viewed through a grid of knowledge constituted by natural history. (p. 128; emphasis added)

Life, in the sense of life itself, is thus a concept linked closely to the rise of the modern life sciences, founded on notions of evolutionary change, the underlying connectedness of all living things, and a biogenetic mechanism of heredity through which life reproduces itself. As the foundational object of the modern life sciences, the concept of life itself does not exist as a thing, as something visible or tangible. Only its traces are accessible, through the forms in which life manifests itself. Like Newtonian gravity, Darwinian life is a principle or force subject to an orderliness decipherable by science, such as the process of natural selection by which evolution is understood to proceed.

Life as Defined by Modern Science

From the vantage point of the modern life sciences, life itself has come to be associated with certain qualities, including movement, the ability to reproduce and to evolve, and the capacity for growth and development. Other criteria for defining life as opposed to nonlife include the capacity to metabolize, in particular through the possession of cells. These characteristics of aliveness in turn comprise key areas in the study of life forms, and in the forms of connectedness and interrelatedness among them. Whereas the comparative anatomy or morphology of animals and plants was the definitive technique for the classification of life forms during the classical period of natural history, it is molecular biology that today provides the primary analytic perspective on the essence of life, which is seen to be DNA, or the genetic code. It is DNA, composed of nucleotide chains that guide the manufacture of essential proteins, that all living beings are said to have in common. Thus DNA is the substance and mechanism of heredity intrinsic to the neo-Darwinian notion of life itself. (For a historical account of Darwinian notions of life itself, see Jacob. For a contemporary view, see Pollack.)

The most definitive accounts of life itself today rely on evolutionary and genetic models. "The possession of a genetic program provides for an absolute difference between organisms and inorganic matter," claims the biologist Ernst Mayr, one of the great twentieth-century exponents of evolution as a unifying theme in modern biological thought(p. 55). "Life should be defined by the possession of those properties which are needed to ensure evolution by natural selection," states John Maynard Smith, one of the leading evolutionary biologists in Britain (p. 7).

In addition to offering the most definitive accounts of life, the modern life sciences provide the most detailed and substantive information on the subject. In the article "Life" written for the Encyclopaedia Britannica, Carl Sagan notes: "A great deal is known about life.… Anatomists and taxonomists have studied the forms and relations of more than a million separate species of plants and animals." A range of biological specialties have together compiled "an enormous fund of information" on the origin, diversity, interaction, and complexity of living organisms and the principles that order their existence (p. 985).

Yet even such definitive accounts of life from established scientific figures are often admittedly provisional. Both within and outside the scientific community there is considerable uncertainty about what is being studied when the subject is life itself. As Sagan notes perfunctorily, "There is no generally accepted definition of life" (p. 985).

Problems in Defining Life

The definition of life is not only contested from within the scientific community; it is also troubled by the proximity of lifelike systems, especially those that are computer-generated, to the requisite features of animate existence. There may well be, as Stephen Levy notes in his account of artificial life, a "particular reluctance to grant anything synthetic or manmade the exalted status of a life-form" (p. 6). Yet insofar as the biogenetic definition of life itself relies on an informational model, of DNA as a message or a code, the distinction between life and nonlife is readily challenged by complex informational systems that are to a degree self-regulating and that have the capacity both to replicate themselves and to evolve. If, as some have claimed (Oyama), information is the modern equivalent of form, then life is transformed from an absolute property into a receding horizon merging with artificial, synthetic, or virtual life. (see also Langton, and Levy).

Today, both the border between human and nonhuman life and the distinction between life and death are increasingly blurred. Genetic science offers the possibility of transspecies recombinations effecting a merging of human and animal body parts. Artificial-life scientists using information technology distinguish computer-generated organisms, which live, evolve, reproduce, and die, from the "wet" life forms they imitate (Levy). Health professionals distinguish degrees of death: dead (in the sense of brain-dead); double dead (respiratory failure); and triple dead (no body parts suitable for donation). Such distinctions indicate the increasing difficulties of establishing the parameters of life and death.

In sum, life itself may be charted along the course of its four-billion-year history to its estimated point of origin, and along this path may be classified and analyzed scientifically according to established principles, such as the operation of natural selection, and specific qualities, such as the possession of DNA. It is from the perspective of the modern life sciences that the most elaborate and definitive accounts of life are constructed, and from these in turn that the concept of life itself emerges. Yet the instability of these definitional parameters, like those of previous eras that they replaced, ensures their continued transformation.

Life as a Moral Issue

Despite the ubiquity and authority of biological definitions of life, they are also reductionist and materialist, relying upon mechanistic and objective terms that are ultimately most meaningful to professional specialists. Most people, when asked "What is life?" do not appeal to Darwinian principles.

Many of the more everyday definitions of life can be classed as processual or phenomenological, referring to the course of events comprising the life of an individual or other entity (including inanimate objects, as in the expression "shelf life"). Expressions such as c'est la vie ("that's life") invoke the fortuitous and inexplicable dimensions of life, very much in contrast to scientific accounts, which emphasize order and predictability even while admitting great uncertainty. Such expressions convey a sense of limits to the capacity for rational understanding, and especially prediction or control, in relation to the vicissitudes of life and living.

The lengthy debate in early modern science concerning mechanism (the presumption that animate and inanimate entities alike are composed of matter, which can be explained through inherent principles of structure and function) versus vitalism (the presumption of an inherently inexplicable vital force differentiating the quick from the dead) opposes the ancient association of lifelike properties with mystery and the sacred to their accessibility through instrumental reason (see Merchant). In relation to the moral questions concerning life—whether as a process, a possession, or a right—the vitalistic notion of life as something inexplicable and deserving of reverence and protection is far more prevalent than the more mechanistic and instrumental account dominant within science. In both secular and religiously derived accounts, life does not need to be fully explicated or rational to be seen as uniquely deserving of protection, especially human life.

The Protection of Life

In his discussion of abortion and euthanasia, two of the most controversial areas of debate concerning human life, philosopher Ronald Dworkin emphasizes the importance of recognizing that life is not exclusively or even primarily understood by many people in terms of scientific explanations, but rather in terms of a value more akin to sacredness. In relation to moral dilemmas, he claims, life does not present itself as a question of objective fact, but rather as a truth, or a "quasi-religious" principle held to be self-evident through "primitive conviction."

Dworkin's approach thus differs from the more utilitarian arguments about the beginnings and endings of life propounded by philosophers and other commentators who use rights or interest-based approaches to questions of the meaning and value of life. In demarcating the value of life as a "quasi-religious" one, something essentially felt rather than reasoned, Dworkin returns the question of the value of life to an older, more traditional paradigm linked to notions of divinity or a vital force.

Social scientists have shown the value of life to be a key symbolic resource in struggles of many kinds, including both ways of life (as in the preservation of ethnic traditions or indigenous cultures) and life forms (such as endangered species). Anthropologist Faye Ginsburg's study of the abortion debate in a midwestern American community, for example, demonstrates the symbolic dimensions of life as a subject of dispute extending to notions of citizenship, nationalism, and the sexual division of labor. Precisely because the preservation of human life may be seen as an absolute moral value, it proves readily amenable to the social function of grounding other beliefs and practices.

Abortion is one of the best-known arenas of controversy in which both definitions of life and the value of human life are paramount and explicitly formulated. Opponents of abortion argue that life begins at conception and therefore that the deliberate termination of a pregnancy is the taking of a human life, which is seen to be immoral or even comparable to murder. Proponents of a woman's right to control her own fertility, including the choice to terminate an unwanted pregnancy, often argue on the basis of consequentialism, that is, that the moral value of an act should be measured in reference to its outcome. Rightsbased claims are used by both sides, antiabortionists stressing the right to life of the fetus, which they argue to be paramount, and pro-choice advocates stressing a woman's right to control her own reproduction, on which they, in turn, place primary importance.

Current legislation on abortion in many industrialized countries, including the United States, invokes a combination of rights-based arguments and biologically based distinctions. Hence, for example, the 1973 U.S. Supreme Court decision in Roe v. Wade, which currently determines abortion law in the United States, combines protection of the individual right to privacy with a biologically based definition of fetal viability as the determinant of the upper time limit for abortion. The same standard holds in Great Britain.

Both the notion of biological viability and the definition of the person to whom rights are ascribed invoke a particular construction of life. Viability, for example, is strictly biologically determined: It is measured by the ability of a fetus to survive biologically. The question of the social viability of a child's life, such as its likelihood of receiving adequate nurture, shelter, protection from disease, or sustenance is not considered part of the criteria valid in determining the morality of a decision to terminate a pregnancy. Feminists have been prominent in the challenge to the notion of the person often used by antiabortionists on similar grounds. It is undeniably the case that an embryo is human, that it is a being, and that it is a form of life. That it is a living human being is therefore undeniable. Yet it is no more or less a living human being in this sense than an egg or sperm cell, or for that matter a blood cell, none of which is considered a person or seen as entitled to civil rights. Increasingly, antiabortionists have used biologically based arguments to support their position, even when it is derived from religious principles. Hence, it is the potential for an embryo—unlike an egg, a sperm, or a blood cell—to develop into a human being that is often stressed. This argument is based on an embryo's possession of a unique genetic blueprint, which some established theologians claim is evidence of ensoulment (see Ford).

Hence, arguments against abortion based on fetal viability, or those that stress the genetic potential of the fetus to develop into a person, are based on a particular model of life, according to which its sanctity may be represented in biogenetic terms. Historian Barbara Duden has called this historically recent turn toward biology as an arbiter of moral decision making the "sacralisation of life itself." Life, in this sense, is not a biological fact but a cultural value, an essentialist belief, or even a fetish.

The Geneticization of Life Itself

Similar claims have been made regarding the biogenetic definition of life as possession of a genetic blueprint. Critical biologists have argued against the genetic reductionism or genetic essentialism such definitions risk (see Hubbard). Social scientists also have warned of the dangers of eugenicism implicit in such a view (Nelkin and Lindee); other scholars have minimized such risks (Kevles).

Advocates of a "strong" genetic essentialism argue not only that genes are the essence of life but that life itself is consequently based on the selfish desire to reproduce itself. From this vantage point, humans are mere epiphenomena of a primordial genetic drive to self-replicate, and human moral or ethical systems are a complex admixture of altruism motivated by strategic sacrifice, which benefits one genetic trajectory or another (Dawkins).

The belief that life processes will one day be subject to much greater control through instrumentalized understandings of their genetic code is the basis for a major expansion in the biotechnology industry, and corresponding scientific research, since the early 1980s. International scientific projects, such as the attempt to map the human genome by sequencing all of the DNA in the twenty-three pairs of human chromosomes, reflect the increasing importance of genes and genetic processes to the understanding of life itself (for a description of the Human Genome Project, see British Medical Association, and Cook-Deegan; for an account of the ethical dimension, see Kevles and Hood; for a critical account, see Hubbard and Wald). In turn, increasing information about the role of genes in heredity will pose new choices and decisions, as well as dilemmas, for many. On the one hand, new diagnostic procedures utilizing genetic screening to detect severe, chronic, degenerative, and often terminal disorders caused by a single gene are claimed to offer greater reproductive choice and control, and the potential to alleviate human suffering and disease. On the other hand, the identification of gene "defects" poses worrisome questions, especially when linked to notions of individual predisposition, genetic selection, and the elimination of "undesirable" traits. Controversies such as that attending the putative discovery of a "gay gene" underscore the dangers of social prejudice wedded to genetic determinism in the name of greater reproductive choice and control.

Altering the genetic code of an individual entity, be it human, plant, or animal, is most controversial when the alteration has the potential to be replicated in subsequent generations, therefore resulting in irreversible and cumulative hereditary effects. Although a distinction is currently maintained between somatic cell gene therapy (genetic alteration of nonreproductive bodily tissue) and germ-line gene therapy (genetic modification of the egg or sperm cells, or the early embryo), this boundary is known to be unstable. Considerable ethical concern therefore surrounds the advent of human gene therapy, now practiced in both Great Britain and the United States (for further discussion, see British Medical Association). The release of genetically engineered organisms into the environment, largely in the form of plants and microorganisms, has also attracted controversy, in particular concerning the labeling of foodstuffs and the limits of acceptable risk.

It is the biogenetic definition of life, then, that informs many of the moral debates about the protection of life, whether human, animal, or environmental—the latter category denoting the ecosystem as a complex "living whole" (for a discussion of protecting life as "biodiversity," see Wilson; also Kellert and Wilson). Confusions about when life begins, for example, as in debates about fetal rights, derive from a biogenetic definition of life, which is continuous: each life form has its origin in the lives of those preceding it, and their connectedness underscores the interrelation of life itself. Given such a definition of life, clear demarcations concerning the beginnings and endings of life, of a life, or of life itself are understandably subject to dispute.

Artificial Life

New techniques for technologically assisting the creation of life (e.g., assisted conception) and for prolonging life or redesigning life (genetic engineering) add to the difficulties of establishing a clear basis for decision making by health professionals, relatives, policymakers, or legislators. Technology now enables the production, extension, and even redesign of life forms, including humans, animals, plants, and microorganisms. Increasingly sophisticated medical technology has affected both the beginning and the ending of human life. Life-support technologies can artificially sustain human life in the context of severely restricted life functions both at the beginning of life (perinatal support) and toward the end of life, in cases where the individual becomes fully dependent on technology for respiration. Cases of prolonged "vegetative" human existence raise difficult questions as a result of the availability of technologically maintained biological viability. Insofar as a person is more than a biological life, difficult decisions concerning continued treatment for a person who is only minimally alive are the inevitable result of modern technology's capacity to sustain baseline survival functions indefinitely.

Technology also affects the creation of life itself. As medical scientists acquire ever greater command of genetic structure, the question of the ethical acceptability of the creation of life forms such as the Harvard "oncomouse," genetically engineered to develop cancer so it can be used in the design of new drugs for the treatment of human disease, must be addressed. The subject of a major patent dispute in the European Parliament, and removed from the market in 1993 by its manufacturer, DuPont, the oncomouse was among the first higher life forms to be defined as a technology, comparable to other forms of laboratory apparatus. As both a mammal and a scientific instrument, the oncomouse inhabits a domain subject to increasing ethical, commercial, and political controversy (Haraway).

Most significant, the oncomouse raises the question of ownership of life, which is established as an inviolable right for humans within the liberal democratic tradition and was described by humanist philosopher John Locke as "ownership of one's person." This principle, used in arguments favoring the emancipation of women and the abolition of slavery (both women and slaves being considered chattels), is more recently evident in disputes concerning body parts. In the landmark case of John Moore v. California Regents, conflict over the use of Moore's body tissue in the design of a drug, through production of an immortal cell line derived from his spleen cells, culminated in a U.S. Supreme Court decision prohibiting the individual ownership of bodily tissue. Ownership of human life in this case was declared not subject to extracorporeal extension.

The question is again different in the case of the "right to life" of the oncomouse, or the "geep," the transspecies hybrid of a goat and a sheep produced through genetic manipulation. Here, the question concerns the deliberate production of a life that brings great suffering to the resultant organism. Only the greater good to humans of such developments can justify their deliberate creation by scientists. But the basis for ethical decision making in such an instance remains indeterminate.

Conclusion

Many of the ethical questions addressed to life itself concern the degree of protection it requires. These questions in turn depend on how life is defined. Whether they concern the beginnings or endings of life, its creation, redesign, or sustenance under technological conditions, the underlying definition of life itself is a fundamental force shaping ethical decision making. Scientifically, life is defined according to the modern life sciences in a biogenetic idiom, which constructs it as a continuous and connected force unto itself, manifested by the self-replicating properties of DNA. In the liberal humanist tradition, human life is also seen as a possession, and the persistent association of life with sacredness is well established. The rights to life, the protection of life, and the quality of life are extended to some degree to other life forms, on the principle of avoiding cruelty and suffering. In none of these areas are definitive boundaries or limits available upon which to base ethical practice. Instead, as definitions of both life and death are subject to ongoing transformation, so are the ethical frameworks brought to bear on the creation, management, and protection of all life forms.

sarah franklin (1995)

bibliography revised

SEE ALSO: Abortion; Animal Welfare and Rights: Ethical Perspectives on the Treatment and Status of Animals; Cloning; Embryo and Fetus; Environmental Ethics; Human Nature; Life Sustaining Treatment and Euthanasia; Life, Quality of; Moral Status; Palliative Care and Hospice; Value and Valuation

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