The December 10, 1999 issue of Science reported that microbiologists may eventually pin down a "minimum genome": the bare bones, molecularly speaking, of what it takes to make a living organism. The interplay of DNA, proteins, and other sub-cellular components in supporting the necessary functions of life – in this case a very simple bacterium – would be completely understood. Nothing mysterious or "protoplasmic" would remain: the very mechanism of life would stand revealed in all its complexity.

The same issue also carried a companion piece by a group of bioethicists on "Ethical Considerations in Synthesizing a Minimal Genome," in which they grapple with what they believe are the worrisome implications of such knowledge. "The attempt to model and create a minimal genome," they say, "represents the culmination of a reductionist research agenda about the meaning and origin of life that has spanned the 20th century." This agenda is far from benign, according to these ethicists, since it challenges the tradition which holds that life is valuable because it is more than "merely physical." Their worry, in essence, is that "The special status of living things and the value we ascribe to life may …be undermined by reductionism."

This is a serious charge, one that might well tend to foster prejudice against science. If a thorough understanding of the mechanics of life necessarily devalues it, then shouldn’t we pull back from the pursuit of biological knowledge? One might expect that the supposed threat of reductionism would be made clear, but in fact the authors don’t sustain their indictment. Rather, their article suggests that reductionism, properly understood, poses little danger. Even with a minimum genome in hand, science simply isn’t in a position to offer definitive pronouncements on the meaning of life.

Their worries rest on a confusion between materialism, the thesis that we essentially are physical creatures, and what might be called strong reductionism, the claim that higher level phenomena, such as human behavior, can be completely explained in terms of its underlying physical mechanisms. Now, some indeed are threatened by materialism, since being "merely" physical undercuts the traditional reassurance that the soul might outlive the body. But it’s not clear that anyone should be worried about strong reductionism, since it’s patently false, and must be distinguished from the bread and butter science of analyzing biological processes, which is what work on the minimal genome consists of.

The ethicists point out that "a reductionist understanding of …human life is not satisfying to those who believe that dimensions of the human experience cannot be explained by an exclusively physiological analysis." True enough, but does anyone really suppose that physiological analysis is even relevant to most human experience? Such strong reductionism is simply a straw man, not an encroaching scientific agenda.

For instance, a thorough understanding of the brain at the neural level, while often necessary for tracing specific mental functions and pathologies, is simply inappropriate for dealing with the everyday psychodrama of our motives, aspirations, disappointments and interpersonal interactions. Even though our having experiences at all may depend on our having properly wired brains, the meaning of experience derives from its social context, not its substrate in physiology. In short, since analytical physical science is irrelevant to domains in which it is useless for explanatory or predictive purposes (which is to say, in much of our lives) its success cannot threaten our dignity.

The ethicists also suggest that extensions of minimal genome research, by specifying the genetic definition of the human organism and its beginnings in utero, will have implications for the abortion debate. Although they don’t tell us precisely what these implications are, they do conclude that "the complex metaphysical issues about the status of human beings cannot be discussed in terms of the presence or absence of a particular set of genes". Quite true, but this is yet another illustration of how physiological analysis is not about to rule our ethical intuitions. Even if we agreed on a definition of human life at the DNA level, all the contentious issues of fetal viability, birth defects, quality of life, and the sometimes conflicting interests of mother and potential newborn, remain to be decided at the social level. Science simply isn’t in competition with social policy debates, although it can help inform them.

But beyond abortion, the most pressing issue, they say, is whether identifying minimal genomes, or perhaps even creating artificial organisms from such blueprints, "constitutes unwarranted intrusion into matters best left to nature; that is, whether work on minimal genomes constitutes ‘playing God’." How much should we intervene in the mechanics of life to suit our desires? An analytical understanding of life’s mechanisms is the key to genetic engineering, both of other creatures and ourselves. If we decide we should play God, then we’ll use the key; if not, we should throw it away.

The authors point out that a spectrum of views exist on playing God. Many of religious persuasions reject it as arrogant hubris; others believe that it should be the no-holds-barred culmination of our capacity for self-design. They themselves recommend a middle path of careful biotechnological stewardship that "would move forward with caution into genomic research and with insights from value traditions as to the proper purposes and uses of new knowledge." They also state that "while there are reasons for caution, there is nothing in the research agenda for creating a minimal genome that is automatically prohibited by legitimate religious considerations."

If, as these ethicists conclude, there is no deep moral objection to our playing God -carefully - then a detailed analysis of life’s mechanisms is simply a means to an end, not an intrinsic threat to the specialness of life or our attachment to human beings and other creatures. And it is these attachments that will shape the ends we seek, and that must channel the use of biotechnology in humane, not monstrous, directions.

Were we to conclude that playing God is wrong, then advanced biology does pose a threat, and we might seek to limit research into what once were the mysteries of life. Indeed, the success of science in showing that simple life forms are mechanisms, albeit astoundingly complex, lends power to what some feel is a deflationary materialism: we no longer need mysterious, non-physical explanations for what life does. The sheer ability to play God, therefore, threatens those who think God is, or should be, a necessary hypothesis at the physical level. They would prefer science to fail, even in its proper arena, and one sure way to ensure failure is to limit biological research.

But in reality, of course, it’s too late not to play God. By knowing that we have the power to know, even a decision to "let nature run its course" is yet another God-like choice, albeit it one that renounces domains of understanding and control. Such a choice would make us a God of the Deists, a passive onlooker of unfolding creation, rather than an active participant in shaping our destiny.

The question, therefore, is not whether we should play God, but what sorts of local gods we will, or should, become. Will materialism (not the straw man of strong reductionism) demoralize us, or will we continue to find meaning in our personal and social lives, even though life itself is understood to be a mechanism? The latter outcome becomes possible if we grasp that our lives’ meaning need not depend on our being ethereal, as opposed to purely physical, creatures. Either way, our response to the success of science will help determine how we play the leading role in which nature has cast us on this planet.

TWC, January 2000