For schoolchildren of the last couple generations, it would be difficult to overstate the influence of the science of genetics. Biology teachers and students around the world were positively giddy with enthusiasm generated by the possibilities of DNA sequencing and the mapping of the human genome. There was a strong expectation that this process, once complete, would grant us intricate knowledge of the source code of the human machine, thus providing a truly scientific answer to the ancient question, “what is man?” By digging deeply enough, we would discover that life emerges out of the inanimate.
The fervor spread rapidly into popular culture. The number of times a film or television show or late-night comic has portentously referenced the discovery that the human being and the chimpanzee share 98 or 99 percent of their DNA, is truly immense. The factoid became a kind of catchphrase by which to denigrate the uniqueness of human life.
Mr. Talbott (whose 2007 book Devices of the Soul I reviewed here) in this excellent if very demanding essay basically takes dynamite to the whole thing. Not being a biologist by any stretch of the imagination, I can only hope to give the barest outline of what the essay contains. In bald summary, in contains the adumbration of a wholesale revision of 30 years of genetic science, a stinging rebuke of grandiose expectations that accompanied it, and above all a reproach of the reductionist presuppositions that undergirded these expectations.
Talbott is a subtle and graceful writer; bringing this intricate and highly-specialized science into a composition accessible by the lay reader is no easy task, yet he manages to accomplish it brilliantly.
How could we hold our heads up with high-browed, post simian dignity when, as the New Scientist reported in 2003, “chimps are human”? If the DNA of the two species is nearly the same, and if, as most everyone seemed to believe, DNA is destiny, what remained to make us special? Such was the fretting on the human side, anyway. To be truthful, the chimps didn’t seem much interested. And their disinterest, it turns out, was far more fitting than our angst.
The bulk of the essay is given to careful explication of the inadequacies of the long-regnant genomic model to explain gene expression. Portions are unavoidably technical in nature. (I had flashbacks to college biology courses.) The New Atlantis helpfully supplies a short glossary at the end to assist the lay reader. But the burden of the main argument is crystal clear: “Today one can only wonder how we became so invested in the almost sacred importance of an abstract and one-dimensional genetic code — a code so thinly connected to the full-fleshed reality of our selves that its entire import could be captured in a skeletal string of four repeating letters.”
“Certainly the idea of a master program seemed powerful to those who were enamored of it. . . . And yet the most striking thing about the genomic revolution is that the revolution never happened.”
The human body is not a mere implication of clean logical code in abstract conceptual space, but rather a play of complexly shaped and intricately interacting physical substances and forces. Yet the four genetic letters, in the researcher’s mind, became curiously detached from their material matrix. In many scientific discussions it hardly would have mattered whether the letters of the “Book of Life” represented nucleotide bases or completely different molecular combinations. All that counted were certain logical correspondences between code and protein together with a few bits of regulatory logic, all buttressed by the massive weight of an unsupported assumption: somehow, by neatly executing an immaculate, computer-like DNA logic, the organism would fulfill its destiny as a living creature. The details would be worked out later.
Mr. Talbott does not neglect the opportunity for some gentle but pointed humor at the expense of the code enthusiasts. One might even call it Chestertonian: “I’m not aware of any pundit who, brought back to reality from the realm of code-fixated cerebration, would have been so confused about the genetic comparison as to invite the chimp home for dinner to discuss world politics.”
What has Talbott particularly exercised is the error of reductionism, the idea that by digging ever deeper, combing with an ever finer grain of analysis, we will discover rational, mechanistic simplicity at the heart of all life. And he shows splendidly how false this is, and how profoundly its presuppositions have led us astray about the nature of human being: “Having plunged headlong toward the micro and molecular in their drive to reduce the living to the inanimate, biologists now find unapologetic life staring back at them from every chromatogram, every electron micrograph, every gene expression profile. Things do not become simpler, less organic, less animate.”
As I read this essay, I became conscious of a kind of chorus in my mind, a hearkening back to an older formulation of human being, now suddenly brought forth again by the stumbling revisions of human science: the body is the material instantiation of the immortal soul.
The genetic code was supposed to reassure us that something like a computational machine lay beneath the life of the organism. The fixity, precision, and unambiguous logical relations of the code seemed to guarantee its strictly mechanistic performance in the cell. Yet it is this fixity, this notion of a precisely characterizable march from cause to effect — and, more broadly, from gene to trait — that has lately been dissolving more and more into the fluid, dynamic exchange of living processes. Organisms, it appears, must be understood and explained at least in part from above downward, from context to subcontext, from the general laws or character of their being to the never-fully-independent details. To realize the full significance of the truth so often remarked in the technical literature today — namely, that context matters — is indeed to embark on a revolutionary adventure. It means reversing one of the most deeply engrained habits within science — the habit of explaining the whole as the result of its parts.
Talbott’s essay is not yet online. I recommend subscribing to The New Atlantis. These quotations amount to a mere sample of the superb elucidation of a revolution in science that is really return, a restoration of older wisdom, and the doom of reductionism.