In response to:

The Pioneer Defended from the December 21, 1995 issue

To the Editors:

I feel obliged to respond to Max Perutz’s angry and polemical review of my book The Private Science of Louis Pasteur [NYR, December 21, 1995]. I am of course disappointed that my book should have been treated in such fashion by a scientist of Perutz’s distinction. I am particularly distressed and baffled by his charge that I am “guilty of unethical and unsavory conduct,” and I think it incumbent upon him to provide evidence for such a serious charge. Nor do I appreciate his unfounded insinuations that I do not understand Pasteur’s science.

I am prepared to defend my book against Perutz’s misrepresentations, although it is hard to do so in the space available here. The problem is that our real disagreements are epistemological, methodological, and ethical in nature. In fact, Perutz uses his review of my book as an occasion to issue indiscriminate and ex cathedra broadsides against all forms of scholarship that display any sympathy for relativist approaches to scientific knowledge, approaches that he calls “a piece of humbug masquerading as an academic discipline.”

In short, Perutz’s review is another salvo in the culture wars that now divide too many scientists from too many historians, philosophers, and sociologists of science. It is of a piece with, but less responsible than, Paul Gross and Norman Levitt’s influential book Higher Superstition: The Academic Left and Its Quarrels with Science (1994). Space does not allow me to begin to articulate my own moderately relativist position, but if Perutz wanted to know where I stand, he could start by reading Bennett M. Berger’s review of Gross and Levitt [Science, May 13, 1994), which captures almost precisely my own point of view.

In any case, readers of Perutz’s review, unless they have also read my book, would never guess that I emphasize early on my belief that Pasteur was a great scientist, that indeed he “deserves his reputation as one of the greatest scientists who ever lived” (p. 10). Nor could they guess any of the following: (1) I never suggested that Pasteur “cheated” when he failed to find perfect agreement between his measurements of optical activity in left-and right-handed tartrates; I merely pointed out that he failed to meet his own impossibly high standards. (Luckily, therefore, I can ignore Perutz’s challenge “to go to the chemistry department at Princeton University…to repeat Pasteur’s experiment,” which I would indeed find hard to replicate.) (2) I never claimed that Pasteur’s ideological positions shaped his research on crystallography, fermentation, anthrax, or rabies. Only in the case of the spontaneous generation debates do I argue that Pasteur’s political and religious views played a significant role—and even then I point out that they merely reinforced Pasteur’s long-standing scientific preconceptions. (3) I agree entirely with Perutz’s position that “scientists rarely follow any of the scientific methods that philosophers have prescribed for them”—indeed, that is a major point of the first half of my book, though it clearly escaped Perutz, whose contribution to our understanding of scientific method is to say that scientists “use their common sense.”

Nor, finally, could innocent readers of Perutz’s review guess that it contains only one direct challenge to me on a matter of fact. That fact concerns an allegedly significant difference between two antiseptic methods of attenuating anthrax vaccines: the carbolic acid used by Pasteur’s competitor Toussaint and the potassium bichromate that was used by Pasteur and his collaborators in the famous public trial at Pouilly-le-Fort. Insinuating once again that I’ve got my science wrong, Perutz writes, without qualification, that “carbolic acid (phenol, as it is now called) kills bacteria, while Chamberland’s bichromate treatment kept them alive.” But in fact carbolic acid does not always kill bacteria or anthrax spores; as with all antiseptics (including Chamberland’s potassium bichromate), the outcome depends on the concentration of the antiseptic and the nature of the solute deployed.

The basic structure and strategy of Perutz’s review is to use facts drawn from my book as the empirical point of departure for his own interpretation of the stories I tell. There is, in principle, nothing wrong with that, but Perutz insists on exaggerating the differences between our interpretations, partly by ignoring my own qualifications. That has the effect of making his interpretations seem more original and his criticisms more trenchant than they really are. In one crucial case, having to do with the Pouilly-le-Fort trial of Pasteur’s anthrax vaccine, Perutz eagerly embraces and presents as if it were his own an interpretation that is in fact broached in my book—namely, that Pasteur may have thought of potassium bichromate as an oxidizing agent and thus as compatible with his general oxygen theory of attenuation (see p. 158).

When Perutz’s review does go beyond the empirical evidence to be found in my book, it is in the form of appeals to what we now know, mainly, it seems, for the purpose of insisting on the “timeless” validity of Pasteur’s ideas, results, or, vastly more important, his practical successes. Intriguingly, it is in these appeals to what we now know that Perutz reveals most clearly his epistemological, methodological, and ethical instincts. Briefly put, Perutz is a thoroughgoing instrumentalist. What matters most to him is that (all of?) Pasteur’s practical techniques were successful. They worked. And, for Perutz, that makes them true, methodologically validated, and ethically justified. So much is this the case that Perutz seems scarcely to care about the truth of Pasteur’s theoretical work: “It is remarkable,” he writes with no trace of irony “that Pasteur achieved his phenomenal practical successes while his theoretical concepts were still far from accurate.”


But it is in the realm of ethics that Perutz’s instrumentalism leads to it’s most striking results. In his discussions of the Pouilly-le-Fort trial and of the first application of the rabies vaccine to a human case (young Joseph Meister), Perutz comes very close to saying that it really doesn’t matter what Pasteur said in his published papers. What difference does it make if Pasteur’s publications gave a misleading account of his actual research on anthrax or rabies vaccines—so long as those vaccines worked? Perutz concludes his account of the Joseph Meister story with this sentence: “Geison’s accusation that Pasteur’s successful attempt to save Meister’s life was unethical is without foundation.” In reaching this conclusion, Perutz once again deploys empirical results drawn from my research in Pasteur’s laboratory notebooks, even as he simplifies my own interpretation to the point of distortion. For technical reasons, as Perutz is clearly aware, there is simply no way to know whether or not Pasteur’s treatment saved Joseph Meister’s life. Yet he uses the word “successful” in the sentence quoted above. What if Pasteur’s attempt had failed? Would Perutz still consider it ethical?

So fixated is Perutz on what works and what we now know that he goes so far as to write that “Geison has little to say about the [currently] correct explanations for the efficacy of vaccines, or for other phenomena, perhaps because his ideological approach denies their very existence.” He is way off target. I do appreciate why scientists and many other readers might want to know the end of the story, so to speak, but this approach is fundamentally ahistorical and inappropriate to any assessment of Pasteur’s scientific achievements in the context of his own time. Here, perhaps, is the crux of the difference between Perutz and me. Unlike Perutz, I am an historian. And Pasteur is an historical figure, not a still-living scientist who knows what we think we know. He now belongs to historians of science, among whom I happily include many thoughtful scientists who have taken the trouble to become familiar with the standards and sensibilities of the discipline. I have sought them out and have benefited greatly from dialogue with them. It is in their presence that I most regret the culture wars. They respect what I do within my disciplinary constraints, and they know that I respect and appreciate what scientists do, including the great and brilliant, if nonetheless very human, Louis Pasteur. To judge from his review of my book, it saddens me to say, I see no prospect of a similarly fruitful dialogue with the distinguished Max Perutz.

Gerald L. Geison

History Department

Princeton University

Princeton, New Jersey

M.F Perutz replies:

I will reply to Geison’s points in turn. I called him guilty of unsavory and unethical conduct, because he used these same words in his unjustified accusations of Pasteur, a good and just man who cannot defend himself because he is dead. I wrote that Geison failed to understand Pasteur’s science because he misinterpreted it. If he did understand it, his false accusations are all the more reprehensible.

Bennett M. Berger criticizes Gross and Levitt’s book for denying that “accepted scientific truths are even partially matters of convention, ‘social construction,’ or consensus formation (that is, pieces of culture)…” whereas “…most relativists believe that knowledge is ultimately warranted by institutionalized communities whose acceptance of an empirical claim certifies it as true.”1 These statements represent a fundamental misunderstanding of scientific knowledge. For example, the Second Law of Thermodynamics states that heat cannot be transferred from a cold to a warm body without performing work. This is neither an empirical claim, nor a social construction, nor a consensus by institutionalized science, but an inexorable law of nature based on the atomic constitution of matter. Scientific laws are different from social ones like “extreme poverty breeds crime,” which may be called a consensus among liberal sociologists. I challenge Berger and Geison to quote a single law of physics or chemistry which can justifiably be described as a social construction. Neither Geison’s book nor Berger’s review does.


Geison does indeed describe Pasteur as a great scientist, but he goes on to accuse him of conduct unworthy of one, and he does not explain that his greatness derives from a long series of fundamental discoveries which have stood the test of time and have much reduced human suffering.

Geison denies having suggested that Pasteur cheated in describing the asymmetry of tartaric acid crystals. Let me repeat what Geison wrote: “Pasteur minimized the difference [between the rotations of polarized light produced by solutions of left- and right-handed crystals]—in effect he explained it away—by pointing to the difficulty of completely separating the two forms [of crystals]. The deviation would ‘probably be the same for well-chosen crystals,’ he now claims” (my italics). This wording implies that the claim was untrue. Had Geison reported Pasteur’s experiment truthfully, he would have stated instead: “Pasteur found a small difference between the two measurements which he attributed correctly to the difficulty of separating the two kinds of crystals.”

Geison stated that Pasteur’s “scientific beliefs were sometimes profoundly shaped by his personal concerns, including his political, philosophical and religious instincts.” Geison now admits that this applied to only one of Pasteur’s discoveries, the impossibility of spontaneous generation, of which Pasteur himself declared: “Neither religion, nor philosophy, nor atheism… has any place here… It is a question of fact. I have approached it without preconceived idea.” Geison presents no evidence for his claim to the contrary.

Geison castigates Pasteur for failing to follow “the scientific method.” Few scientists do.

Toussaint’s anthrax-infected sheep blood treated with solutions of carbolic acid would indeed have left fractions of bacteria alive if the carbolic acid had been sufficiently dilute, but cultures of these bacteria would still have been virulent and unusable as vaccines. By contrast, Pasteur’s oxidized bacteria were heritably attenuated, so that they could be propagated for the preparation of generations of vaccines. This was Pasteur’s great achievement, which made his vaccine superior to Toussaint’s. Geison does not seem to have realized this.

Geison accused Pasteur of “active misrepresentation” for failing to publish that the anthrax vaccine used at the trial at Pouilly-le-Fort was attenuated by bichromate rather than air. I pointed out that both are oxidants producing similar effects; hence the charge of misrepresentation was invalid. If Geison realized that bichromate is an oxidant, his charge is all the more reprehensible.

I accept the validity of Pasteur’s work not merely because of his practical successes, but because his experimental results have never been falsified and their validity has been underpinned and given a strong theoretical basis by modern molecular biology. It is the hallmark of scientific genius to find the right answers even before the rationale for them becomes apparent.

I would like to give a fuller justification of Pasteur’s vaccination of Joseph Meister against rabies than I did in my review. The dog attacked the nine-year-old boy on his way to school, threw him on the ground, and bit him fourteen times on his hands and legs. A bricklayer who saw the scene beat the dog off with an iron bar and picked up the boy, who was covered in blood and dog saliva. The dog returned to his master, the grocer Théodore Vone, and bit him in the arm. Vone shot the dog, whose stomach was found to be full of hay, straw, and bits of wood. These facts leave no doubt that the dog was rabid.

Joseph, his mother, and Vone traveled to Paris to see Pasteur, who assured Vone that his own bite on the arm was superficial and presented no danger. Pasteur then consulted the neurologist Professor Vulpian and Dr. Grancher, a physician in the same laboratory, about Joseph. On seeing the many bites, some very deep, Vulpian expressed the view that Pasteur’s experiments with dogs were conclusive enough to apply his vaccine to Joseph, and the two physicians went ahead.2 This account does not support Geison’s damaging accusation that “boldly, even recklessly, Pasteur was willing to apply vaccines in the face of ambiguous experimental evidence about their safety or efficacy.” Geison asks if I would have considered Pasteur’s attempt ethical even if it had failed. Yes, surely. The dog was clearly rabid, and experience had shown bites of the severity of Joseph Meister’s to be fatal. Therefore Pasteur would have been timid and heartless not to try to save Joseph’s life.

Geison’s question raises the deeper issue of the ethics of trying to save a patient’s life with untried, potentially dangerous treatments. Such dilemmas have often arisen in the history of organ transplants. The most dramatic was the Cape Town surgeon Christiaan Barnard’s first heart transplant. He had practiced heart transplants on dogs when, in November 1967, a colleague referred to him Louis Washkansky, a middle-aged Jewish grocer with acute heart failure. Washkansky had a great zest for life, but he feared he would die soon and implored Barnard to give him a heart transplant, regardless of the risk of an operation never before tried on man. Barnard agreed, but told him he would have to wait for a suitable donor. One Saturday evening three weeks later, a young girl with fatal brain damage following a road accident was brought to the hospital. In an operation that took all night, Barnard transferred her heart to Washkansky. When Barnard emerged from the operating theater next morning, he himself had a pulse rate of 140. Acute anxiety rose again several times when Washkansky’s blood pressure dropped perilously, but eventually the new heart settled down to a regular strong beat, and during the next few days Washkansky’s good humor revived and everyone at the hospital was in high spirits. On the eleventh day after the operation he began to feel unwell, and on the sixteenth he died of septicemia. It was a sad blow for Barnard and all his team, especially since Barnard thought that in his anxiety to prevent rejection of the heart, he had overdosed Washkansky with radiation and immunosuppressants which had made him succumb to bacterial infection.3 All the same, Barnard’s first heart transplant was soon followed by more successful ones. By now, 77 percent of heart transplant patients survive for more than five years. Was Barnard’s first heart transplant unethical? No. Though ambition may have played its part, Barnard’s chief motive, like Pasteur’s, seems to have been compassion.

In 1986, a thirty-four-year-old woman with heart failure, lung hypertension, and inflammation of the liver consulted the Cambridge transplant surgeon Roy Calne. He explained to her that only a combined heart, lung, and liver transplant would cure her, and that this was an operation which had never been tried on a human. The woman pleaded with Calne to go ahead, because her life was no longer worth living. The nine-hour operation succeeded and the woman is still alive and well, but had it gone wrong, people could have accused Calne of killing her.4

I do not justify these pioneering treatments on the grounds that they opened the way to the grounds that they opened the way to the saving of lives in the future, because no medical treatment is justified unless it benefits the patient as an individual, but I justify them as compassionate and courageous attempts, similar to Pasteur’s, to save the lives of dangerously ill patients in the face of unavoidable risks.5

Geison’s last paragraph contrasts himself as a historian with me as an empiricist interested only in practical results. I am proud of being called an empiricist, because experiment and observation form the rock upon which science is built. I quoted practical results in my review, because they appeal to common sense and because they would not exist if the physical laws on which they are based were incorrect. I question Geison’s status as a historian. His letter contains not one single historical or scientific justification for his unfounded accusations of Pasteur. They were accepted at face value by most reviewers and have done Pasteur’s reputation great harm. I am grateful to The New York Review for giving me the chance to set the record right.

This Issue

April 4, 1996