by Lee McIntyre
Did he “care about empirical evidence”? Clearly he did. By controlling the circumstances and testing his ideas against actual experience, Semmelweis was respecting the idea that the cause of childbed fever could not be discerned merely by reason. Was he “willing to change his theory based on new evidence”? Again the answer is yes. Not only did Semmelweis change his hypothesis each time one was refuted, he enlarged it when new information came to light that it was not only cadaveric matter—but also putrid living tissue—that could transfer disease from one body to another. He still did not know the exact mechanism of transfer for the disease (much as Darwin did not know about genetics when he proposed his theory of evolution by natural selection), but the correlation was undeniable. Semmelweis had shown that “lack of cleanliness” was responsible for childbed fever.
Incredibly, this idea was resisted and ignored for decades. Despite Semmelweis’s incontrovertible empirical demonstration that chlorinated hand washing could radically diminish the incidence of childbed fever, his hypothesis was challenged by the majority of medical practitioners. Countless women unnecessarily lost their lives as the stubborn medical establishment resented the implication that they were the ones who were giving their patients childbed fever. They were insulted by the idea that gentlemen could be seen as somehow unclean. With no explanation for how cadaveric matter could be transferring illness, they were reluctant to give up the hypothesis that it was probably the result of “bad air.” Semmelweis was fired from his job and, after further demonstrations of the efficacy of his ideas at other hospitals throughout Europe (still with no acknowledgment from the medical community), he became bitter. Eventually he was committed to an asylum, where he was beaten by guards and died two weeks later of sepsis, a blood infection similar to childbed fever.
In the resistance to Semmelweis’s hypothesis, we can see the flip side of the scientific attitude as well. It is true not only that the presence of the scientific attitude facilitates progress in scientific discovery and explanation, but that its absence can impede it. During the 1840s, the medieval concept that disease resulted from an imbalance in the body’s “four humors” was still widespread. Custom and tradition dictated answers to medical questions more than empirical discovery. It was not until Pasteur’s and Koch’s work on the germ theory of disease in the 1850s, and Lister’s later introduction of antiseptic surgery in 1867, that medicine began to find its scientific footing. Years after Semmelweis’s death, his ideas were vindicated.19
One could be forgiven for thinking that this is all so simple and obvious that the people who ignored Semmelweis must have been fools. How could they have been so stubborn and ignorant to miss what was right in front of them? The answer is that up until the middle of the nineteenth century, medicine did not embrace the scientific attitude. The idea that we could learn about an empirical subject through careful experimentation and observational evidence had already taken hold in the physical sciences. Galileo’s revolution was more than two hundred years old in astronomy. But old ideas held a firm grip on medicine until much later. Indeed, perhaps the most stunning part of the story about childbed fever is not why so many medical practitioners rejected controlled experimentation and learning from empirical evidence, but that Semmelweis ran so far ahead of the pack and embraced it.20
But what excuse do we have for some of today’s scientists who occasionally pursue research that does not live up to this standard? It is perhaps ironic that one of the most compelling demonstrations of scientists’ reliance on the power of evidence can be shown through what some have called the worst example of scientific bungling in the twentieth century. In the spring of 1989, two chemists from the University of Utah—B. Stanley Pons and Martin Fleischmann—held a press conference to announce that they had achieved a sustained nuclear fusion reaction at room temperature. If true, the implications would be enormous, for it would mean that the dream of a clean, cheap, and abundant source of worldwide energy might soon be fulfilled. As expected, scientists met this announcement with enormous skepticism—not least because it was made via press conference rather than the more customary route of publication after rigorous peer review—and set about immediately to try to reproduce Pons and Fleischmann’s results.
And they could not. After a two-month honeymoon in the media, during which time other scientists were handicapped by Pons and Fleischmann’s refusal to share the details of their experiment, it was shown that their work was hopelessly flawed. Accusations of extrascientific meddling ran wide, but in the end all that mattered was appeal to the evidence. Many scientists were extremely embarrassed by this whole episode, especially when books began to appear with titles such as Bad Science, Too Hot to Handle, and The Scientific Fiasco of the Century. Rather than being ashamed of this, scientists might instead have celebrated this occasion to demonstrate the power of scientific skepticism. Despite all of the money, prestige, and media attention, the case was decided by empirical evidence. Though one particular theory (and a couple of reputations) had been spectacularly shot down, this was a victory for the scientific attitude.21
Here one sees a situation that is almost the opposite of what faced Semmelweis. In the case of childbed fever, it was the lone practitioner who insisted that his results were correct, if anyone would bother to look at the evidence. With cold fusion, the original experimenters were perhaps too blinded by the hype surrounding their theory to be more deliberate with their inquiry and release their results only after they had survived a little more methodological self-scrutiny, an attempt at replication, and peer review. Fortunately, with cold fusion, the scientific attitude was embraced by the larger scientific community, who acted as a check against the haste and preference for one’s own theory that can sometimes derail scientific research. For the wider scientific community—some of whom surely had their own interests at stake—the proper way to decide it was to see what evidence could be brought to bear on the problem.
It is not that mistakes are never made in science. Scientists are human and thus subject to all of the traits of ambition, ego, greed, and stubbornness that motivate the rest of the human population. What is remarkable is that in science we have agreed-upon, transparent standards that can be used to adjudicate empirical disputes and try to correct any errors. For Semmelweis, the medical field waited two decades for the right theory to become firmly entrenched. With cold fusion, it took only two months. The difference was the presence of the scientific attitude.
Roots of the Scientific Attitude
The idea that scientists’ attitude is an important feature of science is not new. It has been anticipated by many others, including Popper and Kuhn.22 Popper, in his account of falsification, emphasized the idea that there is a “critical attitude” behind science. Indeed, in some sense Popper seems to feel that a critical attitude is prior to falsifiability.23
What characterizes the scientific approach is a highly critical attitude towards our theories rather than a formal criterion of refutability: only in the light of such a critical attitude and the corresponding critical methodological approach do “refutable” theories retain their refutability.24
In his intellectual autobiography, Popper reflects on how he first came to the idea of falsification and draws a connection between the critical attitude and the scientific attitude:
What impressed me most was Einstein’s own clear statement that he would regard his theory as untenable if it should fail in certain tests. Thus he wrote, for example: “If the redshift of spectral lines due to the gravitational potential should not exist, then the general theory of relativity will be untenable.” Here was an attitude utterly different from the dogmatic attitude of Marx, Freud, Adler, and even more so that of their followers. Einstein was looking for crucial experiments whose agreement with his predictions would by no means establish his theory; while a disagreement, as he was the first to stress, would show his theory to be untenable. This, I felt, was the true scientific attitude. It was utterly different from the dogmatic a
ttitude which constantly claimed to find “verifications” for its favourite theories. Thus I arrived, by the end of 1919, at the conclusion that the scientific attitude was the critical attitude, which did not look for verifications but for crucial tests; tests which could refute the theory tested, although they could never establish it.25
I applaud this account. There is an important aspect of the scientific attitude that is captured in Popper’s insight about falsificationism. I disagree with Popper, however, that the best way to capture this critical attitude is to reduce it to a methodological principle that serves as a criterion of demarcation. As Popper recognizes, there is something special about the attitude that scientists have toward the power of empirical evidence. But need this be a matter of logic?
Kuhn also recognized the importance of the scientific attitude. This fact is often overlooked, owing to the enamored response that Kuhn’s account of science received at the hands of the “Strong Programme” of sociology of science, which argued that all scientific theories—both true and false—could be explained by sociological rather than evidential factors, and were thus in some sense relative to human interests. Kuhn, however, was dismayed by this interpretation of his work and resisted the idea that nature didn’t matter to scientists. As one commentator writes:
Kuhn … was deeply troubled by the developments in the sociology of science initiated by the Strong Programme. … Kuhn was concerned that the proponents of the Strong Programme misunderstood the role that values play in science. … He complained that the Strong Programme’s studies of science “leave out the role of [nature].” … Kuhn, though, insists that nature plays a significant role in shaping scientists’ beliefs.26
While Kuhn took seriously the idea that theories must be compared to one another, they must also be tested against empirical evidence. Kuhn writes:
[The world] is not in the least respectful of an observer’s wishes and desires; quite capable of providing decisive evidence against invented hypotheses which fail to match its behavior.27
Unlike Popper, Kuhn may not have framed this as an “attitude” that stood behind the methodology of science, but Kuhn nonetheless recognized the important role that empirical evidence could play in helping scientists to decide between theories and saw that commitment to the value of empirical evidence was necessary for science to go forward.
One is thus left with the question of why neither Popper nor Kuhn went so far as to make the values of science—either the critical attitude or respect for the idea that nature could overrule our wishes and desires—the basis for distinguishing between science and nonscience.28 For Kuhn, the answer is perhaps easier: although he felt that science was special, and took great pains to come to terms with how science actually worked, he did not wish to tie himself to any formal criterion of demarcation.29 Popper, on the other hand, overtly did wish to do this, so it is perhaps more of a live question why he did not make more of an attempt to find within the critical attitude of science an explanation for what is distinctive about it. One could argue, I suppose, that he did precisely this through his account of falsification. Yet at some level this fails to come to grips with Popper’s strategy of drawing a distinction between the way that science operates versus how philosophers try to justify it, juxtaposed against his deep ambivalence over how to deal with the fact that practical considerations could sometimes threaten the beauty of his logical account of demarcation. Even within one of his clearest statements that falsification is a logical solution to the problem of demarcation, Popper writes: “what is to be called a ‘science’ and who is to be called a ‘scientist’ must always remain a matter of convention or decision.”30 Clearly Popper understood the importance of flexibility, having a critical attitude, and occasional deference to practical matters. Still, he yearned to have an absolutely logical basis for drawing a distinction between what was science and what was not. I think that this distracted him from recognizing the full power of something like the scientific attitude, which may not have seemed “hard” enough to satisfy his mandate for logical demarcation.
An even deeper root of the scientific attitude may be found at the very beginning of when philosophers started to think about the methodology of science. Although he is primarily remembered today for his work on scientific method, the idea that there are special “virtues” that attach to scientific inquiry can be found in Francis Bacon’s 1620 masterpiece The New Organon.31 Here he offers virtues like honesty and openness as inextricably bound up with the good practice of science. Bacon asserts that methodology is important, but it must be embedded within the appropriate values that support it. Indeed, Rose-Mary Sargent has maintained that the modern quest for “objectivity” in the defense of science—where one attempts to bifurcate facts from values—represents a perversion of Bacon’s ideas.32 It may seem ironic that the person most often associated with the idea of scientific method would also uphold the idea that scientific practice must be pursued with the appropriate attitude, but one has only to read the preface and first fifty aphorisms of The New Organon to confirm Bacon’s intention.
In his subsequent work The New Atlantis (1627), Bacon also pushed for the idea that these scientific virtues must be expressed not only by individual practitioners, but also by the community of scientists who would judge and uphold them. In her paper “A Bouquet of Scientific Values,” Noretta Koertge recounts the communal nature of Bacon’s vision for science. She writes, “Bacon’s dream of a new science comprised not only a new methodology but also a community dedicated to the task.”33 Thus we see that a fairly robust account of the scientific attitude has been there all along, practically since the birth of talk about “scientific method.”
Finally, the roots of the scientific attitude may perhaps be appreciated by analogy with another philosophical field that can trace its origins all the way back to Aristotle. In Alasdair MacIntyre’s classic After Virtue, he asks us to consider the merits of his “community practice” approach to normative ethics by way of a chilling thought experiment about science:
Imagine that the natural sciences were to suffer the effects of a catastrophe. A series of environmental disasters are blamed by the general public on the scientists. Widespread riots occur, laboratories are burnt down, physicists are lynched, books and instruments are destroyed. Finally a Know-Nothing political movement takes power and successfully abolishes science teaching in schools and universities, imprisoning and executing the remaining scientists. Later still there is a reaction against this destructive movement and enlightened people seek to revive science, although they have largely forgotten what it was. But all that they possess are fragments: a knowledge of experiments detached from any knowledge of the theoretical context which gave them significance; parts of theories unrelated either to the other bits and pieces of theory which they possess or to experiment; instruments whose use has been forgotten; half-chapters from books, single pages from articles, not always fully legible because torn and charred. Nonetheless all these fragments are reembodied in a set of practices which go under the revived names of physics, chemistry and biology. Adults argue with each other about the respective merits of relativity theory, evolutionary theory and phlogiston theory, although they possess only a very partial knowledge of each. Children learn by heart the surviving portions of the periodic table and recite as incantations some of the theorems of Euclid. Nobody, or almost nobody, realizes that what they are doing is not natural science in any proper sense at all.34
In such a world, what would be missing? Precisely the thing that makes science so special. Even if we had all of the content, knowledge, theories—and even the methods—of science, none of this would make sense without the values, attitudes, and virtues of scientific practice that enabled these discoveries to occur in the first place.
Here the analogy between virtue ethics and science is made explicit.35 In the great ethical debate that has come down to us since Aristotle, some have argued that what makes right acts right is not their adherence to s
ome normative moral theory that purports to delineate our duties based on how well they conform to an ideal standard about consequences (such as utilitarianism) or adherence to some rational principle (such as deontology); rather what makes moral behavior moral is the virtue of the people who perform it. People with good moral character behave morally; morality is what moral people do.
Can a similar move now be made in the debate over science? I do not believe it is quite so simple to say that science is simply what scientists do; as in the debate over ethics, we have also to consider the nature and origin of our values, and how they are implemented and judged by the wider community.36 Nonetheless, the analogy is intriguing: maybe we need to focus less on demarcating scientific from nonscientific theories and more on the virtuous epistemic attitudes that are behind the practices of science.37 Some of this work is just beginning in the field of virtue epistemology, which proceeds by analogy with virtue ethics: if we want to know whether a belief is justified, perhaps we would do well to focus at least some of our attention on the character, norms, and values of the people who hold it. The application of this to problems in the philosophy of science is still quite new, but there has already been some excellent work in applying the insights of virtue epistemology to such thorny problems as underdetermination and theory choice in the philosophy of science.38
I hope it is clear by now that I do not seek to make a priority claim for the scientific attitude. This idea has a long history that goes back through Popper and Kuhn, at least to Francis Bacon, and arguably to Aristotle. What I hope to emphasize is that the scientific attitude has been woefully neglected in the philosophy of science. It can nonetheless play a crucial role in understanding and defending science by illuminating an essential feature that has been missing from many contemporary accounts. If we focus exclusively on method, we may miss what science is most essentially about.
