«Scientific Myth-Conceptions DOUGLAS ALLCHIN Minnesota Center for the Philosophy of Science and Program in History of Science and Technology, ...»
“Undoing” the rhetoric, I hope, shows how it creates its lesson about nature of science, especially about the roles of context and contingency.
First, consider the phrase, “when it was ﬁnally recognized for what it was.” Because originally, in 1928, Fleming hardly envisioned penicillin as the great drug it later became.
He did not strongly advocate treating humans with it until 1940. What happened in those 12 years? Initially, Fleming had indeed been searching for antibacterial agents. But he was not impressed with penicillin’s therapeutic potential. It was not absorbed if taken orally. Taken by injection instead, it was excreted in a matter of hours. For Fleming penicillin was limited, perhaps to topical antisepsis. Hardly momentous. In the ensuing years Fleming used penicillin, but as a bacteriological tool. It suppressed the growth of certain bacterial species and allowed him to culture certain others. That became valuable for manufacturing vaccines—a major task Fleming managed at St. Mary’s Hospital in the 1930s. Meanwhile, Fleming’s research had turned to another group of chemicals, the sulphonamides. Without further work, Fleming’s discovery would have languished, another relatively mundane scientiﬁc ﬁnding (Figure 1). Chance is reserved for Fleming’s ﬁrst observation, not its subsequent development. It sparks the plot, but does not let it wander without direction.
The ultimate pursuit of penicillin in treating human infections was due entirely to another lab, led by Howard Florey in Oxford. In 1938 Ernst Chain, Florey’s associate, began searching for natural antibacterial agents, endeavoring to elucidate their mechanisms more fully. He chose three to study, penicillin just one among them. Chain used Fleming’s 1929 paper, but with his own, quite different, purpose (Figure 1). By early 1939 Chain and Florey began to suspect the medical potential of penicillin. But because of the war effort, Florey had problems securing funds for testing. They also faced several technical challenges. They needed to improve production and puriﬁcation methods, reﬁne an assay to determine the strength of their extracts, and scale up production. After 5 months of work, all with no guarantee of success, they had enough brown powder to test on a few mice, which yielded promising results. While this work reﬂects the bulk of the scientiﬁc process, the traditional story consolidates it as uninteresting drudgery.
Figure 1. Alternative histories in the discovery of penicillin: history as a web, rather than a timeline.
336 ALLCHIN Now, the popular story sometimes notes, “As the world took notice, they swiftly demonstrated that injections of penicillin caused miraculous recoveries in patients with a variety of infections” (Ho, 1999). But the work was hardly minimal. Or swift. For tests on humans, they needed substantially more penicillin. The Oxford labs culturing the mold scaled up from ﬂasks and biscuit tins to hundreds of bedpan-like vessels stored on bookshelves. Puriﬁcation turned from the laboratory to dairy equipment. After the ﬁrst test they had to ﬁnd ways to remove impurities that caused side effects. The tests eventually went quite well, but it had required two professors, ﬁve graduate students, and 10 assistants working almost every day of the week for several months to produce enough penicillin to treat six patients.
While a narrative of science might well celebrate hard work, here the “swift” pace linking insight to triumph seems primary. Also, emphasis on the downstream work would reduce the dramatic role of the chance event as central.
Fleming noticed Florey and Chain’s striking results. Yet he did not disturb his research agenda. He knew that penicillin’s value still lay in economical mass production. Thus, the research—and, in a sense, the discovery—was still not complete, and certainly not Fleming’s alone. One can now imagine the details of 3 more years of work before the U.S.
could produce enough penicillin to treat a quarter-million patients per month. The ultimate achievement was indeed monumental and worth celebrating in the classroom. However, the story exaggerates the scale of Fleming’s role, thereby creating a distorted image of genius in science (as true also for Mendel, Case 1). Fleming, Florey, and Chain all shared the Nobel Prize in 1945. If Fleming “changed the course of history” (Ho, 1999), it was not without the help of Florey, Chain and dozens, even hundreds, of technicians. An aura surrounds Fleming, like an inspiring tale of a scientist winning the lottery: vicariously, we thrill in his good fortune. But the story inﬂates the role of one scientist at the expense of representing how science happened.
While this episode exempliﬁes the role of “chance,” popularizers nevertheless credit Fleming, as hero, with noticing the antibacterial properties: the “‘Eureka’ moment” that Ho (1999) described. Others, however, besides Fleming had noticed the antibacterial properties of Penicillium, including Joseph Lister, John Tyndall, Ernest Duschene, Louis Pasteur, and Jules Joubert (Figure 1).4 Fleming was not as uniquely perceptive nor as singularly lucky as the popular story suggests. Moments of mythic insight may involve large doses of opportunity, context, and contingency, not just intellectual prowess. Given other circumstances, the history might not have included Fleming at all. But this history is harder to package into a compelling narrative.
Classroom histories tend to follow only a single linear plot. The narrative connects Fleming directly to the status of penicillin today. Other plot lines and scientists become invisible. The outcome thus seems inevitable. But to understand the process of science as it moves forward, the alternative futures and potential alternative discoveries are essential (Figure 1).
Educators must portray “science-in-the-making,” advancing blindly, not “science-made” unfolding predictably (Latour, 1987). Contingency does not deﬁne just the moment in 1928 In 1871, Joseph Lister (noted for introducing antiseptic practice into surgery) found that a mold in a sample of urine seemed to be inhibiting bacterial growth. In 1875 John Tyndall reported to the Royal Society in London that a species of Penicillium had caused some of his bacteria to burst. In 1877 Louis Pasteur and Jules Joubert observed that airborne microorganisms could inhibit the growth of anthrax bacilli in urine that had been previously sterilized. Most dramatically, Ernest Duchesne had completed a doctoral dissertation in 1897 on the evolutionary competition among microorganisms, focusing on the interaction between E. coli and Penicillium glaucum. Duchesne reported how the mold had eliminated the bacteria in culture. He had also inoculated animals with both the mold and a lethal dose of typhoid bacilli, showing that the mold prevented the animals from contracting typhoid. He urged more research. Following his degree he went into the army and died of tuberculosis before pursuing that research. Chance, here, worked against his discovery bearing fruit (Judson, 1981).
SCIENTIFIC MYTH-CONCEPTIONS 337 when Fleming turned his attention to the discarded, now a famous culture in the tray of lysol. It permeates the whole process. It may not ﬁt a standard plot trajectory conveniently.
In celebrating Fleming, therefore, one might focus instead on his habits: the context that fostered the moment so often depicted as critical. Fleming was not known for running a “tidy” lab. Abandoned cultures heaped unattended in a basin would not have been at all unusual—less “chance” than the story suggests. Such “messy” circumstances invite the unexpected. For molecular biologist Max Delbr¨ ck, this promotes discovery. He labeled it u the “principle of limited sloppiness” (Fisher & Lipson, 1988, p. 184; Judson, 1981, p. 71).
In addition, Fleming was accustomed to play and pursue “idle” curiosities. At ﬁrst, he simply found the halo of inhibited bacterial growth interesting. Later in the day he toured the building trying to interest his colleagues—who were largely unimpressed: no promise of miracle cures yet. There was no “instant of great personal insight and deductive reasoning” (Ho, 1999), as dictated by the heroic plot template. Rather, personal amusement. Later, Fleming drew pictures with Penicillium on culture plates and watched them “develop” over several days as the bacteria grew in the negative spaces. A teacher might have pined that Fleming was frequently not “on task.” A very different image of science emerges when one sees sloppiness and play as contributing signiﬁcantly to Fleming’s “chance” moment. The plot becomes less algorithmic.
In the traditional history, science appears to rely on an exceptional individual and a rare moment of insight to propel it forward. The fuller story reminds us, dramatically, how it might have been otherwise. The conventional story is narratively cozy. It celebrates modesty and good luck. Science appears formulaic and sure, even where the critical event is portrayed as chance. A more authentic history, however, reveals the many contingencies and contextual factors that shape the scientiﬁc enterprise through multitude potential pathways (Figure 1).
CASE 4: IGNAZ SEMMELWEISMy fourth case concerns tragic death from childbed fever in Vienna in the mid-1800s and the discovery of the importance of handwashing by Ignaz Semmelweis (Carter, 1983).
Here is how the case appeared recently in the Journal of College Science Teaching (Colyer,
2000) and on a major website of case studies5 :
Ignaz Semmelweis, a young Hungarian doctor working in the obstetrical ward of Vienna General Hospital in the late 1840s, was dismayed... that nearly 20% of the women under his and his colleagues’ care... died shortly after childbirth. [Students pause here to hypothesize causes.] One day, Semmelweis and some of his colleagues were... performing autopsies... One of Semmelweis’ friends... punctured his ﬁnger with the scalpel. Days later, [he] became quite sick, showing symptoms not unlike those of childbed fever. [Students are again asked what to do next.] In an effort to curtail the deaths in his ward due to childbed fever, Semmelweis instituted a strict handwashing policy amongst his male medical students and physician colleagues in “Division I” of the ward... Mortality rates immediately dropped from 18.3% to 1.3%... [Students interpret.] For economy, I have edited the content heavily, while hoping to preserve the sense of the original.
Colyer’s approach is certainly not unique. See, for example, Episode 622 from the radio series “Engines of Our Ingenuity” (also on the web). The romanticism of popular historical narratives, especially among medical professionals, is evident in such sensational labels as “conquest,” “tribute,” “pioneer” and “prophet,”all found in titles of articles on Semmelweis in medical journals from the last two decades.
338 ALLCHIN Despite the dramatic reduction in the mortality rate in Semmelweis’ ward, his colleagues and the greater medical community greeted his ﬁndings with hostility or dismissal...
Semmelweis was not able to secure the teaching post he desired... In 1860, [he] ﬁnally published his principal work on the subject of puerperal sepsis but this, too, was dismissed... the years of controversy and repeated rejection of his work by the medical community caused him to suffer a mental breakdown. Semmelweis died in 1865 in an Austrian mental institution. Some believe that his own death was ironically caused by puerperal sepsis.
Semmelweis is the quintessential scientiﬁc hero, defending scientiﬁc truth in the face of adversity. The predominant tone is tragic. But the lessons about science are essentially the same, albeit often inverted. The exercise above aims appropriately at reviving sciencein-the-making (Case 3) by engaging students in situated decision-making. Still, a sense of drama is crucial. Making the story compelling largely depends on suppressing relevant facts and perspectives. It is worth considering how the history is traded for drama.
First, authors sometimes portray Semmelweis as the person who noticed the problem of childbed fever, although the reputation of the Division I ward was notorious, even among patients. This creates a stronger protagonist. But it also inﬂates his genius.