Bully for Brontosaurus

by Stephen Jay Gould

  But consider the poor horses. Theirs was once a luxuriant bush, yet they barely survive today. Only one twig (the genus Equus, with horses, zebras, and asses) now carries all the heritage of a group that once dominated the history of hoofed mammals—and with fragility at that, for Equus died in the land of its birth and had to be salvaged from a stock that had migrated elsewhere. (In a larger sense, horses form one of three dwindling lines—tapirs and rhinos are the others—that now represent all the diversity of the formerly dominant order Perissodactyla, or odd-toed ungulates, among hoofed mammals. This mighty group once included the giant titanotheres, the clawed chalicotheres, and Baluchitherium, the largest land mammal that ever lived. It now hangs on as a remnant in a world increasingly dominated by the Artiodactyla, or even-toed ungulates—cows, deer, antelope, camels, hippos, giraffes, pigs, and their relatives.)

  This is life’s little joke. By imposing the model of the ladder upon the reality of bushes, we have guaranteed that our classic examples of evolutionary progress can only apply to unsuccessful lineages on the very brink of extermination—for we can linearize a bush only if it maintains but one surviving twig that we can falsely place at the summit of a ladder. I need hardly remind everybody that at least one other mammalian lineage, preeminent among all in our attention and concern, shares with horses the sorry state of reduction from a formerly luxuriant bush to a single surviving twig—the very property of extreme tenuousness that permits us to build a ladder reaching only to the heart of our own folly and hubris.

  12 | The Chain of Reason versus the Chain of Thumbs

  THE Weekly World News, most lurid entry in the dubious genre of shopping mall tabloids, shattered all previous records for implausibility with a recent headline: “Siamese Twins Make Themselves Pregnant.” The story recounted the sad tale of a conjoined brother-sister pair from a remote Indian village (such folks never hail from Peoria, where their non-existence might be confirmed). They knew that their act was immoral, but after years of hoping in vain for ordinary partners, and in the depths of loneliness and frustration, they finally succumbed to an ever-present temptation. The story is heart-rending, but faces one major obstacle to belief: All Siamese twins are monozygotic, formed from a single fertilized egg that failed to split completely in the act of twinning. Thus, Siamese twins are either both male or both female.

  I will, however, praise the good people at Weekly World News for one slight scruple. They did realize that they had created a problem with this ludicrous tale, and they did not shrink from the difficulty. The story acknowledged that, indeed, Siamese twins generally share the same sex, but held that this Indian pair had been formed, uniquely and differently, from two eggs that had fused! Usually, however, Weekly World News doesn’t even bother with minimal cover-ups. Recently, for example, they ran a screaming headline about a monster from Mars, just sighted in a telescope and now on its way to earth. The accompanying photo of the monster showed a perfectly ordinary chambered nautilus (an odd-looking and unfamiliar creature to be sure). I mean, they didn’t even bother to retouch the photo or to hide in any way their absurd transmogrification of a marine mollusk into an extraterrestrial marauder!

  The sad moral of this tale lies not with the practices of Weekly World News, but with the nature of a readership that permits such a publication to prosper—for if Weekly World News could not rely, with complete confidence, on the ignorance of its consumers, the paper would be exposed and discredited. The Siamese twin story at least showed a modicum of respect for the credulity of readers; the tale of the Martian monster records utter contempt both for the consuming public and for truth in general.

  We like to cite an old motto of our culture on the factual and ethical value of veracity: “And ye shall know the truth, and the truth shall make you free” (John 8:32). But ignorance has always prospered, serving the purposes of demagogues and profit-mongers. An overly optimistic account might try to link our increasing factual knowledge with the suppression of cruelties and abuses ranging from execution for witchcraft to human sacrifice for propitiating deities. But this hope cannot be sustained, for no century has exceeded our own in quantity of imposed cruelty (as “improvements” in the technology of genocide and warfare more than balance any overall gains in sensibility). Moreover, despite a great spread in the availability of education, the favored irrationalisms of the ages show no signs of abatement. Presidential calendars are still set by astrologers, while charlatans do a brisk business in necklaces made of colored glass masquerading as crystals that supposedly bathe believers in a salutary and intangible “energy.” An astounding percentage of “educated” Americans think that the earth might be less than 10,000 years old, even while their own kids delight in dinosaurs at the local museum.

  The champions of beleaguered rationalism—all heroes in my book—have been uncovering charlatans throughout the ages: from Elijah denouncing the prophets of Baal to Houdini exposing the tricks of mediums to James Randi on the trail of modern hoaxers and hucksters. Obviously, we have not won the war, but we have developed effective battle strategies—and would have triumphed long ago were our foe not able, like the Lernean Hydra, to grow several new heads every time we lop one off. Still, tales of past victories—including the story of this essay—are not only useful as spurs of encouragement; they also teach us effective methods of attack. For reason is timeless, and its application to unfamiliar contexts can be particularly instructive.

  How many of us realize that we are invoking a verbal remnant of “the greatest vogue of the 1780s” (according to historian Robert Darnton) when we claim to be “mesmerized” by a wonderful concert or a beautiful sunset? Franz Anton Mesmer was a German physician who had acquired wealth through marriage to a well-endowed widow; connections by assiduous cultivation (Mozart,* a valued friend, had staged the first performance of his comic opera Bastien und Bastienne at Mesmer’s private theater); and renown with a bizarre, if fascinating, theory of “animal magnetism” and its role in human health. In 1778, Mesmer transferred to Paris, then the most “open” and vibrant capital of Europe, a city embracing the odd mixture so often spawned by liberty—intellectual ferment of the highest order combined with quackery at its most abject: Voltaire among the fortune tellers; Benjamin Franklin surrounded by astrologers; Antoine Lavoisier amidst the spiritualists.

  Mesmer, insofar as one can find coherence in his ideas at all, claimed that a single (and subtle) fluid pervaded the universe, uniting and connecting all bodies. We give different names to this fluid according to its various manifestations: gravity for planets in their courses; electricity in a thunderstorm; magnetism for navigation by compass. The same fluid flows through organisms and may be called animal magnetism. A blockage of this flow causes disease, and cure requires a reestablishment of the flux and a restoration of equilibrium. (Mesmer himself never went so far as to ascribe all bodily ills to blocked magnetism, but several disciples held this extreme view, and such a motto came to characterize the mesmeric movement: “There is only one illness and one healing.”)

  Cure of illness requires the intervention of an “adept,” a person with unusually strong magnetism who can locate the “poles” of magnetic flow on the exterior of a human body and, by massaging these areas, break the blockage within to reestablish the normal flux. When working one on one, Mesmer would sit directly opposite his patient, establishing the proper contact and flow by holding the sufferer’s knees within his own, touching fingers, and staring directly into her face (most patients were women, thus adding another dimension to charges of exploitation). Mesmer, by all accounts, was a most charismatic man—and we need no great psychological sophistication to suspect that he might have produced effects more by power of suggestion than by flow of any fluid.

  In any case, the effects could be dramatic. Within a few minutes of mesmerizing, sensitive patients would fall into a characteristic “crisis” taken by Mesmer as proof of his method. Bodies would begin to shake, arms and legs move violently and involuntarily, teeth ch
atter loudly. Patients would grimace, groan, babble, scream, faint, and fall unconscious. Several repetitions of these treatments would reestablish magnetic equilibrium and produce cures. Mesmer carried sheaves of testimonials claiming recovery from a variety of complaints. Even his most determined critics did not deny all cures, but held that Mesmer had only relieved certain psychosomatic illnesses by the power of suggestion and had produced no physical effects with his putative universal fluid.

  Mesmer’s popularity required the development of methods for treating large numbers of patients simultaneously (such a procedure didn’t hurt profits either), and Mesmer imposed high charges, in two senses, upon his mostly aristocratic crowd. Moreover, as a master of manipulation, Mesmer surely recognized the social value of treatment in groups—both the reinforcing effect of numerous crises and the simple value of conviviality in spreading any vogue as a joint social event and medical cure. Mesmer therefore began to magnetize inanimate objects and to use these charged bodies as instruments of unblocking and cure.

  A patient falls into a Mesmeric crisis as the eponymous hero himself performs a cure. THE BETTMANN ARCHIVE.

  Many contemporary descriptions and drawings of Mesmer’s sessions depict the same basic scene. Mesmer placed a large vat, called a baquet, in the center of a room. He then filled the baquet with “magnetized” water and, sometimes, a layer of iron filings as well. Some twenty thin metal rods protruded from the baquet. A patient would grab hold of a rod and apply it to the mesmeric poles of his body. To treat more than twenty, Mesmer would loop a rope from those who surrounded the baquet (and held the iron rods) to others in the room, taking care that the rope contained no knots, for such constrictions impeded the flux. Patients would then form a “mesmeric chain” by holding a neighbor’s left thumb between their own right thumb and forefinger, while extending their own left thumb to the next patient down the line. By squeezing a neighbor’s left thumb, magnetic impulses could be sent all the way down the chain.

  Mesmer, whether consciously or not, surely exploited both the art and politics of psychosomatic healing. Everything in his curing room was carefully arranged to maximize results, efficiency, and profit. He installed mirrors to reflect the action and encourage mass response; he heightened the effect with music played on the ethereal tones of a glass harmonica, the instrument that Benjamin Franklin had developed; he employed assistants to carry convulsive patients into a “crisis room” lined with mattresses, lest they should hurt themselves in their frenzy. To avoid the charge of profitmongering among the rich alone, Mesmer provided a poor man’s cure by magnetizing trees and inviting the indigent to take their relief gratis and alfresco.

  I don’t want to commit the worst historical error of wrenching a person from his own time and judging him by modern standards and categories. Thus, Franz Mesmer was not Uri Geller teleported to 1780. For one thing, historical records of Mesmer are scanty, and we do not even know whether he was a simple charlatan, purveying conscious fakery for fame and profit, or a sincere believer, deluded no less than his patients in mistaking the power of suggestion for the physical effects of an actual substance. For another, the lines between science and pseudoscience were not so clearly drawn in Mesmer’s time. A strong group of rationalists was laboring to free science from speculation, system building, and untestable claims about universal harmonies. But their campaign also demonstrates that all-embracing and speculative systems were still viewed by many scholars as legitimate parts of science in the eighteenth century. Robert Darnton, who has written the best modern book on mesmerism, describes the French intellectual world of the 1780s (Mesmerism and the End of the Enlightenment in France, 1968):

  They looked out on a world so different from our own that we can hardly perceive it; for our view is blocked by our own cosmologies assimilated, knowingly or not, from the scientists and philosophers of the 19th and 20th centuries. In the 18th century, the view of literate Frenchmen opened upon a splendid, baroque universe, where their gaze rode on waves of invisible fluid into realms of infinite speculation.

  Still, whatever the differing boundaries and cultural assumptions, the fact remains that Mesmer based his system on specific claims about fluids, their modes of flow, and their role in causing and curing human disease—claims subject to test by the ordinary procedures of experimental science. The logic of argument has a universality that transcends culture, and late eighteenth century debunking differs in no substantial way from the modern efforts. Indeed, I write this essay because the most celebrated analysis of mesmerism, the report of the Royal Commission of 1784, is a masterpiece of the genre, an enduring testimony to the power and beauty of reason.

  Mesmerism became such a craze in the 1780s that many institutions began to worry and retaliate. Conventional medicine, which offered so little in the way of effective treatment, was running scared. Empirical and experimental scientists viewed Mesmer as a throwback to the worst excesses of speculation. People in power feared the irrationalism, the potential for sexual license, the possibility that Mesmer’s mass sessions might rupture boundaries between social classes. Moreover, Mesmer had many powerful friends in high circles, and his disturbing ideas might spread by export. (Mesmer counted Lafayette among his most ardent disciples. King Louis XVI asked Lafayette before he departed for America in 1784: “What will Washington think when he learns that you have become Mesmer’s chief journeyman apothecary?” Lafayette did proselytize for Mesmer on our shores, although Thomas Jefferson actively opposed him. Lafayette even visited a group of Shakers, thinking that they had discovered a form of mesmerism in their religious dances.)

  The mesmeric vogue became sufficiently serious that Louis XVI was persuaded to establish a Royal Commission in 1784 to evaluate the claims of animal magnetism. The commission was surely stacked against Mesmer, but it proceeded with scrupulous fairness and thoroughness. Never in history has such an extraordinary and luminous group been gathered together in the service of rational inquiry by the methods of experimental science. For this reason alone, the Rapport des commissaires chargés par le roi de l’examen du magnétisme animal (Report of the Commissioners Charged by the King to Examine Animal Magnetism) is a key document in the history of human reason. It should be rescued from its current obscurity, translated into all languages, and reprinted by organizations dedicated to the unmasking of quackery and the defense of rational thought.

  The commissioners included several of France’s leading physicians and scientists, but two names stand out: Benjamin Franklin and Antoine Lavoisier. (Franklin served as titular head of the commission, signed the report first, and designed and performed several of the experiments; Lavoisier was the commission’s guiding spirit and probably wrote the final report.) The conjunction may strike some readers as odd, but no two men could have been more appropriate or more available. Franklin lived in Paris, as official representative of our newborn nation, from 1776 to 1785. American intellectuals sometimes underestimate Franklin’s status, assuming perhaps that we revere him faute de mieux and for parochial reasons—and that he was really a pipsqueak and amateur among the big boys of Europe. Not at all. Franklin was a universally respected scholar and a great, world-class scientist in an age when nearly all practitioners were technically amateurs. As the world’s leading expert on electricity—a supposed manifestation of Mesmer’s universal fluid—Franklin was an obvious choice for the commission. His interest also extended to smaller details, in particular to Mesmer’s use of the glass harmonica (Franklin’s own invention) as an auxiliary in the precipitation of crises. As for Lavoisier, he ranks as one of the half-dozen greatest scientific geniuses of all time: He wrote with chilling clarity, and he thought with commanding rigor. If the membership contains any odd or ironic conjunction, I would point rather to the inclusion of Dr. Guillotin among the physicians—for Lavoisier would die, ten years later, under the knife that bore the good doctor’s name (see Essay 24).

  The experimental method is often oversold or promulgated as the canonical, or ev
en the only, mode of science. As a natural historian, I have often stressed and reported the different approaches used in explaining unique and complex historical events—aspects of the world that cannot be simulated in laboratories or predicted from laws of nature (see my book Wonderful Life, 1989). Moreover, the experimental method is fundamentally conservative, not innovative—a set of procedures for evaluating and testing ideas that originate in other ways. Yet, despite these caveats about nonexclusivity and limited range, the experimental method is a tool of unparalleled power in its appropriate (and large) domain.

  Lavoisier, Franklin, and colleagues conclusively debunked Mesmer by applying the tools of their experimental craft, tried and true: standardization of complex situations to delineate possible causal factors, repetition of experiments with control and variation, and separation and independent testing of proposed causes. The mesmerists never recovered, and their leader and namesake soon hightailed it out of Paris for good, although he continued to live in adequate luxury, if with reduced fame and prestige, until 1815. Just a year after the commission’s report, Thomas Jefferson, replacing Franklin as American representative in Paris, noted in his journal: “animal magnetism dead, ridiculed.” (Jefferson was overly optimistic, for irrationalism born of hope never dies; still, the report of Franklin and Lavoisier was probably the key incident that turned the tide of opinion—a subtle fluid far more palpable and powerful than animal magnetism—against Mesmer.)

  The commissioners began with a basic proposition to guide their testing: “Animal magnetism might well exist without being useful, but it cannot be useful if it doesn’t exist.” Yet, any attempt to affirm the existence of animal magnetism faced an intense and immediate frustration: The mesmerists insisted that their subtle fluid had no tangible or measurable attributes. Imagine the chagrin of a group of eminent physical scientists trying to test the existence of a fluid without physical properties! They wrote, with the barely concealed contempt that makes Lavoisier’s report both a masterpiece of rhetoric and an exemplar of experimental method (the two are not inconsistent because fair and scrupulous procedures do not demand neutrality, but only strict adherence to the rules of the craft):