Synopsis
Book by Gould Stephen Jay
Extrait
Chapter 1
I Have Landed
As a young child, thinking as big as big can be and getting absolutely nowhere for the effort, I would often lie awake at night, pondering the mysteries of infinity and eternity—and feeling pure awe (in an inchoate, but intense, boyish way) at my utter inability to comprehend. How could time begin? For even if a God created matter at a definite moment, then who made God? An eternity of spirit seemed just as incomprehensible as a temporal sequence of matter with no beginning. And how could space end? For even if a group of intrepid astronauts encountered a brick wall at the end of the universe, what lay beyond the wall? An infinity of wall seemed just as inconceivable as a never-ending extension of stars and galaxies.
I will not defend these naÍve formulations today, but I doubt that I have come one iota closer to a personal solution since those boyhood ruminations so long ago. In my philosophical moment—and not only as an excuse for personal failure, for I see no sign that others have succeeded—I rather suspect that the evolved powers of the human mind may not include the wherewithal for posing such questions in answerable ways (not that we ever would, should, or could halt our inquiries into these ultimates).
However, I confess that in my mature years I have embraced the Dorothean dictum: yea, though I might roam through the pleasures of eternity and the palaces of infinity (not to mention the valley of the shadow of death), when a body craves contact with the brass tacks of a potentially comprehensible reality, I guess there's no place like home. And within the smaller, but still tolerably ample, compass of our planetary home, I would nominate as most worthy of pure awe—a metaphorical miracle, if you will—an aspect of life that most people have never considered, but that strikes me as equal in majesty to our most spiritual projections of infinity and eternity, while falling entirely within the domain of our conceptual understanding and empirical grasp: the continuity of etz chayim, the tree of earthly life, for at least 3.5 billion years, without a single microsecond of disruption.
Consider the improbability of such continuity in conventional terms of ordinary probability: Take any phenomenon that begins with a positive value at its inception 3.5 billion years ago, and let the process regulating its existence proceed through time. A line marked zero runs along below the current value. The probability of the phenomenon's descent to zero may be almost incalculably low, but throw the dice of the relevant process billions of times, and the phenomenon just has to hit the zero line eventually.
For most processes, the prospect of such an improbable crossing bodes no permanent ill, because an unlikely crash (a year, for example, when a healthy Mark McGwire hits no home runs at all) will quickly be reversed, and ordinary residence well above the zero line reestablished. But life represents a different kind of ultimately fragile system, utterly dependent upon unbroken continuity. For life, the zero line designates a permanent end, not a temporary embarrassment. If life ever touched that line, for one fleeting moment at any time during 3.5 billion years of sustained history, neither we nor a million species of beetles would grace this planet today. The merest momentary brush with voracious zero dooms all that might have been, forever after.
When we consider the magnitude and complexity of the circumstances required to sustain this continuity for so long, and without exception or forgiveness in each of so many components—well, I may be a rationalist at heart, but if anything in the natural world merits a designation as "awesome," I nominate the continuity of the tree of life for 3.5 billion years. The earth experienced severe ice ages, but never froze completely, not for a single day. Life fluctuated through episodes of global extinction, but never crossed the zero line, not for one millisecond. DNA has been working all this time, without an hour of vacation or even a moment of pause to remember the extinct brethren of a billion dead branches shed from an evergrowing tree of life.
When Protagoras, speaking inclusively despite the standard translation, defined "man" as "the measure of all things," he captured the ambiguity of our feelings and intellect in his implied contrast of diametrically opposite interpretations: the expansion of humanism versus the parochiality of limitation. Eternity and infinity lie too far from the unavoidable standard of our own bodies to secure our comprehension; but life's continuity stands right at the outer border of ultimate fascination: just close enough for intelligibility by the measure of our bodily size and earthly time, but sufficiently far away to inspire maximal awe.
Moreover, we can bring this largest knowable scale further into the circle of our comprehension by comparing the macrocosm of life's tree to the microcosm of our family's genealogy. Our affinity for evolution must originate from the same internal chords of emotion and fascination that drive so many people to trace their bloodlines with such diligence and detail. I do not pretend to know why the documentation of unbroken heredity through generations of forebears brings us so swiftly to tears, and to such a secure sense of rightness, definition, membership, and meaning. I simply accept the primal emotional power we feel when we manage to embed ourselves into something so much larger.
Thus, we may grasp one major reason for evolution's enduring popularity among scientific subjects: our minds must combine the subject's sheer intellectual fascination with an even stronger emotional affinity rooted in a legitimate comparison between the sense of belonging gained from contemplating family genealogies, and the feeling of understanding achieved by locating our tiny little twig on the great tree of life. Evolution, in this sense, is "roots" writ large.
To close this series of three hundred essays in Natural History, I therefore offer two microcosmal stories of continuity—two analogs or metaphors for this grandest evolutionary theme of absolutely unbroken continuity, the intellectual and emotional center of "this view of life."* My stories descend in range and importance from a tale about a leader in the founding generation of Darwinism to a story about my grandfather, a Hungarian immigrant who rose from poverty to solvency as a garment worker on the streets of New York City.
Our military services now use the blandishments of commercial jingles to secure a "few good men" (and women), or to entice an unfulfilled soul to "be all that you can be in the army." In a slight variation, another branch emphasizes external breadth over internal growth: join the navy and see the world.
In days of yore, when reality trumped advertisement, this motto often did propel young men to growth and excitement. In particular, budding naturalists without means could attach themselves to scientific naval surveys by signing on as surgeons, or just as general gofers and bottle washers. Darwin himself had fledged on the Beagle, largely in South America, between 1831 and 1836, though he sailed (at least initially) as the captain's gentleman companion rather than as the ship's official naturalist. Thomas Henry Huxley, a man of similar passions but lesser means, decided to emulate his slightly older mentor (Darwin was born in 1809, Huxley in 1825) by signing up as assistant surgeon aboard HMS Rattlesnake for a similar circumnavigation, centered mostly on Australian waters, and lasting from 1846 to 1850.
Huxley filled these scientific Wanderjahre with the usual minutiae of technical studies on jellyfishes and grand adventures with the aboriginal peoples of Australia and several Pacific islands. But he also trumped Darwin in one aspect of discovery with extremely happy and lifelong consequences: he met his future wife in Australia, a brewer's daughter (a lucrative profession in this wild and distant outpost) named Henrietta Anne Heathorn, or Nettie to the young Hal. They met at a dance. He loved her silky hair, and she reveled in his dark eyes that "had an extraordinary way of flashing when they seemed to be burning-his manner was most fascinating" (as she wrote in her diary).
Huxley wrote to his sister in February 1849, "I never met with so sweet a temper, so self-sacrificing and affectionate a disposition." As Nettie's only dubious trait, Hal mentioned her potential naiveté in leaving "her happiness in the hands of a man like myself, struggling upwards and certain of nothing." Nettie waited five years after Hal left in 1850. Then she sailed to London, wed her dashing surgeon and vigorously budding scientist, and enjoyed, by Victorian standards, an especially happy and successful marriage with an unusually decent and extraordinarily talented man. (Six of their seven children lived into reasonably prosperous maturity, a rarity in those times, even among the elite). Hal and Nettie, looking back in their old age (Hal died in 1895, Nettie in 1914), might well have epitomized their life together in the words of a later song: "We had a lot of kids, a lot of trouble and pain, but then, oh Lord, we'd do it again."
The young and intellectually restless Huxley, having mastered German, decided to learn Italian during his long hours of boredom at sea. (He read Dante's Inferno in the original terza rima during a year's jaunt, centered upon New Guinea.) Thus, as Huxley prepared to leave his fiancée in April 1849 (he would return for a spell in 1850, before the long five-year drought that preceded Nettie's antipodal journey to their wedding), Nettie decided to give him a parting gift of remembrance and utility: a five-volume edition, in the original Italian of course, of Gerusalemme liberata by the great Renaissance poet Torquato Tasso. (This epic, largely describing the conquest of Jerusalem by the First...
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