Never say die.

The Dream of Eternal Life Biomedicine, Aging, and Immortality Mark Benecke Translated by Rachel Rubenstein Columbia University Press, $27.95, 256 pp.

The reasons why old age seems unhappy and is feared, Cicero made Cato say in De Senectute, are four: "the first because it distances us from occupations; the second because it enfeebles the body; third, because it deprives us of most pleasures; and fourth, because it is not far from death." More than two thousand years later, many in America would like to correct that statement by reducing the four reasons to a single one, the second in the mentioned list. For a culture distinctly partial to youth is apt to believe that, if only bodily vigor and the wholesome freshness of young years were preserved, there would be nothing to oppose the perfect happiness of the human race. Cicero and his contemporaries, in order to avert the ills of old age, could do little more than implore the mercy of capricious gods or develop an implausible Stoic philosophy that regarded personal loss and bereavement as no ills at all (and, consequently, felt little inclined to alleviate the suffering of others). We, in contrast, have developed science and technology, which are concrete, positive, and highly effective tools. And of these, biomedical science and technology have of late achieved such feats as infuse new potency in the ancient dream of eternal life.

Hence the timeliness of Mark Benecke's The Dream of Eternal Life. Benecke is a molecular biologist, and a popularizer of biomedical themes. His book's subtitle, Biomedicine, Aging, and Immortality, circumscribes the subject matter of his work. The topics, however, being of monumental proportions, can only be cursorily sketched in less than three hundred pages.

The author's intent appears to be pedagogic. The opening chapter deals with basic biological concepts: the cell; the structure of DNA; the genetic control of crucial physiologic processes; and the genes that--ensconced somewhere in the threadlike, twisted structure of the DNA molecule--presumably determine senescence. For in the puissant imagery now almost universal among science writers, DNA is the supreme, all-encompassing "master plan" or "blueprint." True, most contemporary biologists reject the idea of genetic determinism, and Benecke is no exception. But in professing to do so, they give the impression of making a token concession to academic restraint and good manners, while elsewhere they betray the intimate conviction that everything in human life, from baldness and homosexuality, to alcoholism and violent behavior, is directly caused by flawed genes. Thus, what we believed all along to be profound individual maladjustments, or social problems, or matters of collective moral responsibility, turn out to be simple chemical errors: a few nucleotides out of place in the spiraled DNA molecule.

In a wide-ranging chapter titled "No One Wants to Die," Benecke collates some quite varied material: near-death experiences; ancient Assyrian and Egyptian ideas on death; vampirism and the superstition that drinking blood restores a lost vigor (he retells the speculative tale that patients with a genetic disease named porphyria, who appear livid, with parched, bleeding lips, abnormal dentition, and intolerance to bright sunlight, and who were once counseled to drink fresh blood to ameliorate their condition, may have given rise to the belief in vampires); hypothetical causes of senescence, such as free radicals, metabolic, nutritional, and other influences; cases of extreme longevity; melatonin; vitamins; and biorhythms that are the "pacemakers," as it were, of life's tempo. The material is interesting, if a bit motley, and is framed in a concise, lucid language. Readers ought to find it informative and enjoyable.

At the end of this variegated chapter, the author writes: "According to what we know today, a long life is determined about two-thirds by genetics and one-third by environmental influences." Statements of this kind I find disconcerting. I agree with the late Stephen Jay Gould that dichotomies of this style--"nature versus nurture"--generally verge on the nonsensical. The fullness of human life is not amenable to disaggregation into components with allotable percentages to the genetic and the environmental. The two are inextricably combined. Moreover, history teaches that attribution of the respective proportions changes in the course of time. Today, genetics rides the crest of popularity, but as Gould predicted, "the worm will turn again," and the current fascination with nature will become enthusiasm for nurture. Then, the experts will find different percentages.

The book's next section roams as widely as the preceding ones. We find discussions on the changing definition of death, presumably justified on the premise that, if we yearn for immortality, we ought to know what it is we are trying to avoid. The survey covers clinical observations on delayed and accelerated aging; cloning; and the companies that profit by the gruesome industry of freezing corpses of people who hope for a second stint in this vale of tears. Customers encounter a two-fee scale: full body price or "head only" at a discount. The latter leads naturally into a consideration of the consequences of a still purely hypothetical (Providence be thanked!) brain transplant.

The fourth section is devoted to the environment, for, as the opening subtitle correctly declares, "We're alive only if the earth is too." A broad perspective is maintained, with allusions to our planet's fauna and flora, and mankind's effort to cope with their progressive devastation. The book closes with a relatively short chapter of dual theme, namely: the current efforts at decoding the meaning of the human genome in its totality, and the biological necessity of death.

In sum, but for the author's undeniable expository mastery, The Dream of Eternal Life's ambitious reach might turn into aimless wandering. The impact of biotechnology on our lives is now of unprecedented magnitude, and public education on basic principles is urgent. Benecke contributes substantially to this end.

In a strict sense, of course, to dream of eternal life is to have an impossible, erratic flight of fancy. What we may reasonably hope for is alleviation of the grievous ills that now torment the aged and render them dependent on others. Once free from physical misery, those among the elderly who managed to accumulate personal inner resources--sensibility, intellectual or objective interests, prudence, mature appreciation of their fellow creatures, and the like--would be able to realize their own happiness and enhance that of others. For, unlike the young, the old are not distracted by tumultuous passions and bad influences, or degraded by vanity, extravagance, and complete absorption in their own selves. We can also expect that medicine will significantly expand the average life span, but there is a limit to what may be achieved. For life is immersed in the unidirectional flow of time; every vital function is, in a way, irrevocable. And death is an implacable judge. Death's verdict is a final "no" to all our plaintive pleadings for return, for hope, for restoration, or for continuity.

F. Gonzalez-Crussi, M.D., is a writer and emeritus professor of pathology at Northwestern University Medical School. He lives in Chicago.