15
An Epilog on Human Culture
Most of this chapter has focused on constraints imposed by life’s origin at a left wall of minimal complexity, followed by a passive trend to the right as life diversified. As in all other examples for this book, I emphasized how explicit consideration of all the variation (the "full house") can engender proper understanding, while the old Platonic strategy of abstracting the full house as a single figure (an average construed as an archetype, or an extreme example to excite our wonder or horror), and then tracing the pathway of this single figure through time, usually leads to error and confusion.
My two major examples in this book—the extinction of 0.400 hitting in baseball and the absence of a driven trend to complexity in the history of life—consider different sides of the same analytical strategy (studying the full house rather than the abstracted essence). The baseball example speaks of encroachment upon a right wall of human limitations; the history of life invokes expansion away from a left wall of minimal complexity. In this second example, I viewed life as expanding passively into a rightward domain of increasing elaboration—but I never addressed the principle that some constraint might eventually limit the spread by acting as a right wall. The baseball example illustrates the shaping power of right walls at the apogee of human achievement—and we should also consider their potential role in the history of human life.
We live in a world of limits. Goethe, citing an old German proverb, wrote: Es ist dafür gesorgt, dass die Bäume nicht in den Himmel wachsen (it is ordained that trees cannot grow to heaven). Such mechanical constraints are easily appreciated (and quantified) for objects of human or natural construction. My native state of New York has adopted a motto of one word: Excelsior—or "ever upward." But not all the way to heaven.... I once stood before a picture window on the twenty-fifth floor of a building at Fifth Avenue and 38th Street in Manhattan—and I could see the entire history of twentieth-century efforts in maximal height rising before me at a single glance.
As a patriotic native and an architecture buff, I was thrilled. The world’s tallest buildings, one after the other: the Park Row Building at 15 Park Row, breaking the record at three hundred eighty-six feet in 1899; the Metropolitan Life Tower at Madison and 24th, clocking in at seven hundred feet in 1909; the Woolworth Building on South Broadway (792 feet in 1913); a quick turn of the head to the Chrysler Building on Lexington and 42nd (1,048 feet in 1930); facing back downtown for the greatest impact of all, the massive Empire State Building just four blocks south at Fifth and 34th, occupying almost half my viewing area (1,250 feet in 1931, with extension to 1,475 feet by a TV tower installed in 1951); and finally the Twin Towers of the World Trade Center, way downtown and small by visual comparison in the distance (1,350 feet in 1976). After this, I understand that some building in Chicago went even higher, but no real New Yorker would acknowledge such a travesty.
Such an ever-rising sequence of Excelsior might give the false impression of potential extension without limit. But we should really draw the diametrically opposite conclusion that each new contender "stretches the envelope" of severe constraint; perhaps people do, but buildings, like trees, cannot reach heaven. Each higher push is an engineering marvel, straining the limits of available technology. And the increments of increase decline with time, just as improvement in sports records tails off as humans approach the right wall of biomechanical limitation (see Part Three). The Met Life Tower of 1909 doubled the previous record. The last few champions have added less than 10 percent to the height of the previous record holder.
In this chapter, I want to discuss the most powerful putative case for worrying about right walls in the history of human life—the saga of cultural change through time. I discussed, in the preceding chapters in Part Four, why the basic character of natural, or Darwinian, evolution—a process whose causes only produce local adaptation, not general progress— can only engender a passive trend to greater complexity in the form of a small right tail that cannot wag the dog of life’s main weight at a constant bacterial mode. In this context, the issue of right walls hardly comes up— because they exist in some far uncharted distance, and life as a whole has not yet been seriously impacted by them (although individual lineages often encounter specific limits of biomechanical and other kinds of constraint—the tree that cannot reach heaven).
But human cultural change is an entirely distinct process operating under radically different principles that do allow for the strong possibility of a driven trend to what we may legitimately call "progress" (at least in a technological sense, whether or not the changes ultimately do us any good in a practical or moral way). In this sense, I deeply regret that common usage refers to the history of our artifacts and social organizations as "cultural evolution." Using the same term—evolution—for both natural and cultural history obfuscates far more than it enlightens. Of course, some aspects of the two phenomena must be similar, for all processes of genealogically constrained historical change must share some features in common. But the differences far outweigh the similarities in this case. Unfortunately, when we speak of "cultural evolution," we unwittingly imply that this process shares essential similarity with the phenomenon most widely described by the same name—natural, or Darwinian, change. The common designation of "evolution" then leads to one of the most frequent and portentous errors in our analysis of human life and history—the overly reductionist assumption that the Darwinian natural paradigm will fully encompass our social and technological history as well. I do wish that the term "cultural evolution" would drop from use. Why not speak of something more neutral and descriptive—"cultural change," for example?
The obvious main difference between Darwinian evolution and cultural change clearly lies in the enormous capacity that culture holds—and nature lacks—for explosive rapidity and cumulative directionality. In an unmeasurable blink of a geological eyelash, human cultural change has transformed the surface of our planet as no event of natural evolution could ever accomplish at Darwinian scales of myriad generations. (Natural catastrophes of a physical nature, like the bolide that triggered the great Cretaceous extinction, may wipe out many forms of life in a geological moment, but no known process can produce natural evolutionary change at anything like the speed and extent of human cultural transformation; the impressive and maximal rapidity of the Cambrian explosion lasted some 5 million years.)
The most impressive contrast between natural evolution and cultural change lies embedded in the major fact of our history. We have no evidence that the modal form of human bodies or brains has changed at all in the past 100,000 years—a standard phenomenon of stasis for successful and widespread species, and not (as popularly misconceived) an odd exception to an expectation of continuous and progressive change. The Cro-Magnon people who painted the caves at Lascaux and Altamira some fifteen thousand years ago are us—and one look at the incredible richness and beauty of this work convinces us, in the most immediate and visceral way, that Picasso held no edge in mental sophistication over these ancestors with identical brains. And yet, fifteen thousand years ago, no human social grouping had produced anything that would conform with our standard definition of civilization. No society had yet invented agriculture; none had built permanent cities. Everything that we have accomplished in the unmeasurable geological moment of the last ten thousand years— from the origin of agriculture to the Sears Building in Chicago, the entire panoply of human civilization for better or for worse—has been built upon the capacities of an unaltered brain. Clearly, cultural change can vastly outstrip the maximal rate of natural Darwinian evolution.
Among the many differences in deep principle between natural evolution and cultural change, two stand out as the motors of cultural rapidity and directionality:
1. TOPOLOGY. Darwinian evolution at the species level and above is a story of continuous and irreversible proliferation. Once a species (defined by inability to reproduce with members of any other species) becomes separate from an ancestral line, it remains distinct forever. Species do not amalgamate or join with others. Species interact in a rich variety of ecological ways, but they cannot physically join into a single reproductive unit. Natural evolution is a process of constant separation and distinction.
Cultural change, on the other hand, receives a powerful boost from amalgamation and anastomosis of different traditions. A clever traveler may take one look at a foreign wheel, import the invention back home, and change his local culture fundamentally and forever. One brace of guns, one bevy of war chariots, imported with the engineers and trades-men to keep them in working order, can transform a limited and peaceful state into an expanding engine of conquest. The explosively fruitful (or destructive) impact of shared traditions powers human cultural change by a mechanism unknown in the slower world of Darwinian evolution.
2. MECHANISM OF INHERITANCE. Darwinian evolution works by the indirect and inefficient mechanism of natural selection. Effectively random variation must first provide the raw material of change, and natural selection—a negative force that can make nothing by itself—then acts by eliminating most variants and preserving those individuals fortuitously better adapted to changing local environments. The summation of favorable variants over many generations leads to evolutionary change. Local improvement rises upon the hecatomb of countless deaths; we get to a "better" place by removing the ill-adapted, not by actively constructing an improved version.
Anyone can easily envision a more direct and efficient mechanism: Why can’t organisms figure out what would do them good, develop those adaptive features by dint of effort during their lifetimes, and then pass those improvements to their offspring in the form of altered heredity? We call such a putative mechanism "Lamarckism," or "the inheritance of acquired characters." Natural evolution would go like gangbusters if heredity happened to work in this manner. But, unfortunately, it doesn’t. Inheritance is Mendelian, not Lamarckian. An organism may struggle to "improve" throughout its life—the giraffe stretching its neck upward, or the blacksmith developing a strong right arm, to cite the clichéd and ridiculous examples of our schoolday textbooks—but these advantageous "acquired characters" cannot be passed to offspring because they do not alter the genetic material that will build the next generation. Too bad, but so be it. Darwinism works well enough, if slowly and indirectly.
But cultural change, on a radical other hand, is potentially Lamarckian in basic mechanism. Any cultural knowledge acquired in one generation can be directly passed to the next by what we call, in a most noble word, education. If I invent the first wheel, my brainchild is not condemned to oblivion by hereditary impassability (as any purely bodily improvement would be). I just teach my children, my apprentices, my social group, how to make more wheels. The point is so simple, yet so profound. Reading, writing, filming, teaching, practicing, apprenticing, learning— all the distinctly human activities that pass knowledge between generations—act as the Lamarckian boosters of our cultural history. This uniquely and distinctively Lamarckian style of human cultural inheritance gives our technological history a directional and cumulative character that no natural Darwinian evolution can possess.
The net result of these two crucial differences between natural evolution and cultural change—the enormous boosts given to the cultural mode by amalgamation of lineages and Lamarckian inheritance—also specifies a key distinction crucially relevant to the central theme of this book. Natural evolution includes no principle of predictable progress or movement to greater complexity. But cultural change is potentially progressive or self-complexifying because Lamarckian inheritance accumulates favorable innovations by direct transmission, and amalgamation of traditions allows any culture to choose and join the most useful inventions of several separate societies.
I should introduce the obvious caveat at this point. A potential for inherent "progress" provides no guarantee of realization in actuality. The radical contingency of all history can intervene in a thousand potential ways. A capacity for technological accumulation does not guarantee that all cultures will avail themselves of this potentially mixed blessing. In fact, several great societies have made conscious decisions not to pursue technological "progress" to the inevitable destruction of an old order. At a crucial point in the history of human life, imperial China decided to scrap the technology of interoceanic shipping and navigation that, if pursued, might well have converted the central historical theme of European westward expansion to an alternative tale of Oriental eastward exploration in the New World. In the early 1640s, after a century of relative openness to Western inventions, especially to the musketry that permitted their assumption and consolidation of power, Japan’s ruling Tokugawa shogunate severed all future accumulation and banned most of what had been imported. So complete and sudden was the cutoff that Japanese inhabitants of various trading cities established abroad were not even allowed to return home. All Western trade was reduced to the merest trickle. Only two Dutch ships could arrive each year. They could dock only at Nagasaki, and all Dutch traders had to live on the artificial island of Dejima, connected to the rest of Nagasaki by a narrow and easily guarded causeway.
Moreover, and obviously, accumulating technological "progress" need not lead to cultural improvement in any visceral or moral sense—and may just as well end in destruction, if not total extinction, as various plausible scenarios, from nuclear holocaust to environmental poisoning, suggest. I have long been impressed by a potential solution, perhaps whimsically proposed, but worthy of serious attention in my view, to the problem of why we haven’t been contacted by the plethora of advanced civilizations that ought to inhabit other solar systems in our universe. Perhaps any society that could build a technology for such interplanetary, if not intergalactic, travel must first pass through a period of potential destruction where technological capacity outstrips social or moral restraint. And perhaps no, or very few, societies can ever emerge intact from such a crucial episode.