Copyright © 1990 by Kluwer Academic Publishers.
(This article originally appeared in Experimental Inquiries, edited by H. E. Le Grand, (Kluwer Academic Publishers, 1990), pp. 137-166. It appears at MendelWeb, for non-commercial educational use only, with the kind permission of the author and Kluwer. Although you are welcome to download this text, please do not reproduce it without the permission of the author and Kluwer Academic Publishing.)
Gregor Mendel's short treatise "Experiments on Plant Hybrids" is one of the triumphs of the human mind. It does not simply announce the discovery of important facts by new methods of observation and experiment. Rather, in an act of highest creativity, it presents these facts in a conceptual scheme which gives them general meaning. Mendel's paper is not solely a historical document. It remains alive as a supreme example of scientific experimentation and profound penetration of data. It can give pleasure and provide insight to each new reader-and strengthen the exhilaration of being in the company of a great mind at every subsequent study.
(Curt Stern, and Eva Sherwood 1966, p. v)
There is no greater legend in the history of science than that of the experiments of Gregor Mendel. Three moments in this legend are extraordinary: 1) how in the 1860s, Mendel single-mindedly discovered the laws governing the inheritance of individual characters; 2) how the scientific world failed to recognize the monumental importance of these findings during his life-time; 3) the remarkable "rediscovery" in 1900 of what later came to be called Mendelism. Thus, after an eclipse of some 35 years Mendel's experiments became universally hailed as providing a foundation for a chain of scientific research that has culminated with the Darwinian evolutionary synthesis of the 1930s and 40s, and the spectacular accomplishments of modern molecular genetics. Loren Eisely (1961:211) summarized this legend beautifully when he wrote:
Mendel is a curious wraith in history. His associates, his followers, are all in the next century. That is when his influence began. Yet if we are to understand him and the way he rescued Darwinism itself from oblivion we must go the long way back to Brunn in Moravia and stand among the green peas in a quiet garden. Gregor Mendel had a strange fate: he was destined to live one life painfully in the flesh at Brunn and another, the intellectual life of which he dreamed, in the following century. His words, his calculations were to take a sudden belated flight out of the dark tomblike volumes and be written on hundreds of university blackboards, and go spinning through innumerable heads.
If Mendel and his experiments on peas had been neglected for 35 years they are alive and well today and show no signs of dwindling in curiosity and significance. Since Mendel's "vindication" at the turn of the century, more attention has been given to analyzing and commenting on his experiments than any other experiments in biology. Why is this? What is the power of these experiments? Here we meet with an apparent paradox. Although almost everyone agrees that these experiments are central to modern biology, there is no consensus about their exact significance. Indeed, despite attempts to understand Mendel and his experiments, the great heap of literature addressing his motives, his experimental protocols, his own beliefs about heredity and evolution, and the exact nature of his discovery remains largely incoherent. There are almost as many different interpretations as there are commentators. In fact, just about every possible scenario has been offered to account for them. The interpretations that will be briefly examined in the present study may be summarized as follows:
2. Mendel was a good Darwinian. His experimental protocols and reported results can be explained on the assumption that he had no objections to Darwinian selection theory. (R.A.Fisher 1936)
3. Mendel was not directly concerned with evolution at all. He placed it on the back burner while he investigated the laws of inheritance. (Gasking 1959)
4. Mendel rejected evolutionary theory. (Callender 1988)
7. Some of Mendel's data was falsified. (R.A.Fisher 1936)
9. Mendel's reported experiments set out in his paper of 1866 are wholly fictitious. (Bateson 1909)
Most of these interpretations aimed to explain the long neglect of Mendel's experiments. In general, "long neglect" accounts look for similarities between what became accepted as Mendelism during the earlier 20th century and what Mendel wrote in 1866: a study of the transmission of individual traits, independent assortment of characters, statistical analysis of their transmission. In sum, they see the concepts and methods that later became the principal way of investigating the mechanism of inheritance and discerning the nature of hereditary variations, which in turn provided the fuel for the evolution. Simply put, the problem is this: if Mendel's experiments provided a foundation for genetics and evolutionary investigations, why was this not recognized in his day? Why, for example, was there not a meeting of the minds, so to speak, between Darwin and Mendel? This problem was first raised by geneticists, who offered a variety of reasons for the long neglect of Mendel's work. The explanations offered began with social considerations about the alleged obscurity of the journal in which Mendel published his results. It has been suggested that Mendel was professionally an outsider, an amateur, a monk, "abbot of Brunn," and that anticlerical attitudes may have interfered in the proper evaluation of his claims (see Dunn 1965: 19).
Most commentators have emphasized conceptual reasons; they single out conflicting theories of heredity and competing research interests as being responsible for Mendel's neglect. But, here too the reasons given are often divergent and conflicting. Some have claimed that Mendel's work on the laws of inheritance was overshadowed by the attention given to larger questions concerning the mechanism of evolution with the appearance of The Origin of Species in 1859. (Bateson 1909:2; Dunn 1965:19). Others have argued that Mendel was trying to provide evidence for evolution and was therefore neglected by non-evolutionists (Fisher, 1936). On the other hand, it has often been claimed that Mendel's methodology was unorthodox. According to this argument, hybridists of Mendel's times investigated the transmission of "species characters" to determine whether or not new species could be formed by hybrids. Mendel's approach differed; he investigated single character differences, not species differences. His statistical manner of analysis was at odds with the current ways of investigating hybrids (see, for example, Gasking 1959, Dunn 1965). Yet this interpretation, like all the others, has been contradicted. Long ago, the geneticist Conway Zirkle (1951) showed that Mendel's statistical approach was not unorthodox compared to existing traditions. In recent years, the view that Mendel's work was not "ahead of his time" has been strengthened by the writings of historians and sociologists of science.
Studies by Callender (1988), Brannigan (1979, 1981) and Olby (1979) have challenged the "long neglect" accounts of Mendel in a wholesale way. The main thrust of these studies leads to the conclusion that Mendel did not make the major intellectual leaps commonly assumed. The principal conclusions of these investigations can be summarized briefly as follows:
First, contrary to accepted opinion, Mendel was not trying to discover new laws of inheritance. He belonged to a tradition of hybridists who were examining the possibility that hybridization might be a source of evolution. They were interested in making new species simply out of combinations of existing ones. That is, new species did not result from selection of small hereditary differences as Darwinians would have it, they were formed simply out of the hybridization of existing ones. The central question for Mendel and his fellow hybridists was whether or not hybrids were variable or constant (breed-true). If they were constant they might mark the beginning of new species. Mendel approached this problem with the conception of constant and independently transmitted characters. The laws of inheritance were only of concern to him in as much as they bore on the question of the evolutionary role of hybrids. This program of 19th century hybridists contrasts with that of geneticists at the turn of the century who were not interested in hybridization as a means of speciation, but used hybridization as a means to determine the nature of hereditary variability which in turn provided the fuel for evolution. So Mendel's problematic, the way he understood his work, was different from that of geneticists at the turn of the century (Brannigan 1979, 1981; Olby 1979; Callender 1988). Second, Mendel did not develop the concept of paired hereditary factors equivalent to the alleles of classical geneticists (Olby 1979). Third, Mendel did not enunciate a "law of segregation" which he thought might be applicable to all plant hybrids (Callender 1988). These accounts then provide us with a radically different image of Mendel. Mendel was not the lonely pioneer who ran ahead of his contemporaries, someone who made an intellectual leap so great that its significance could not be understood by them, but rather someone whose work was firmly situated in the context of the mid 19th century research program on hybridization. Only later, at the turn of the century, the meaning of Mendel' work was "misinterpreted" by geneticists to produce the legend of the long neglect.
Despite the new efforts to put Mendel and his work into his historical context, there still is no consensus about Mendel's intentions, what his historical context "really" was. For example, Brannigan (1979:448, 1981:106) suggests that Mendel saw hybridization as a solution to the evolution of organic forms. Based on Zirkle's work, he (1979: 440 1981:105) remarked, "If anything, Mendel's reputation was modest not because he was so radically out of line with his times but because his identity with his contemporaries was so complete!" Callender (1988:72), who does not refer to Brannigan, tends to disagree. He argues forcefully that Mendel, " was an opponent of the fundamental principle of evolution itself." According to Callender, Mendel had adopted "a sophisticated form of the doctrine of Special Creation as proposed by Linneaus." That is, he accepted the general fixity of species but acknowledged a limited number of cases in which new species had arisen through hybridization. On Callender's view, then, Mendel, would be a good scientific creationist! To support his claim, Callender (1988: 41) argued in part on the basis of what was missing in Mendel's papers: a concept of hereditary mutation. Moreover, Callender argues that Mendel had a record of misrepresenting the views of others in his papers and that this, combined with his opposition to evolutionary theory, "are quite sufficient to account for the failure of his theories to make any significant impression on serious scientific opinion of his time." Callender (1988:73) claims that Olby, who tends to agree with his interpretation of Mendel's attitude towards evolution, distorts or misunderstood Callender's arguments.
One might throw one's hands up in despair: where is the truth? My objective in this overview is not to try to find the key to unlock the mystery of Mendel's "real" intentions. I am not, the reader may be relieved to know, going to provide a new "definitive" reading of Mendel's work, offer still another reconstruction of his thought process or try to provide further detail of his place in the 19th century. To understand the significance of Mendel's experiments, such an approach would be fruitless. One important generality is already certain, Mendel's experiments were not held to be significant in his day. They are held to be significant only in the Twentieth Century. Moreover, as we shall see, Mendel's place in Twentieth Century science is not determined by his writings of the 1860s. Indeed, in view of the diversity of the accounts about Mendel, it is reasonable to suppose that his writings do not even constrain the diverse interpretations offered. We have to look elsewhere to understand them. How then, has this Austrian monk, and his experiments on garden peas come to move so many people? Again, the answer to this question lies more in the stories written about Mendel and his experiments, than in the stories written by Mendel. This is not to suggest that the discovery or "Great Neglect" is "more an artefact arising from the inadequacies of academic research than a genuine problem deriving from the actual course of historical development", as Callender (1988:41) claims or that "The Great Neglect" is a product of historians of science, not of scientific history." (Callender 1988:72) On the contrary, as we shall see, these stories are a genuine problem derived from the actual course of the historical development of genetics.
1. Making a Discoverer
We begin our exploration of the significance of Mendel's experiments by a discussion of how the story about his discovery, neglect and rediscovery was invented. From whence did it originate? What were the contexts in which Mendel's contribution was raised to the status of a discovery? The geneticist, Alexander Weinstein (1977) showed clearly that the belief that Mendel's work was virtually unknown before 1900 dates back to statements made at the turn of the century by the "rediscoverers" of "Mendel's laws", de Vries, Correns and Tschermak. Each insisted that they had read Mendel only after they had conducted their experiments and reached their own interpretations. He understands this as an attempt on their part to protect their priority. Each of the "rediscoverers", Weinstein (1977:361) argued, "was anxious to have his work regarded as independent of the work of Mendel and of the other rediscoverers." In fact, there is a widespread belief among commentators on Mendel's "rediscovery" that De Vries at first intended to suppress any reference to Mendel, but his plans were interrupted when he found that Correns and Tschermak were going to refer to him (see Sturtevant 1965: 27). This is based on de Vries's failure to mention Mendel when he first announced his discovery in a short abstract written in French. He mentioned Mendel only later in two longer papers, one in German and one in French where he remarked that it was "trop beau pour son temps" (see Weinstein 1977).
Brannigan, a sociologist, took this suggestion one step further and argued that Correns, realising that he had lost priority to de Vries, referred to Mendel's work as a strategy to minimize his loss and effectively to undermine the priority of De Vries' claim to the discovery. This suggestion is supported by Correns' reaction to de Vries' abstract in terms of a priority dispute in his paper of 1900 entitled "G. Mendel's Law Concerning the Behaviour of Progeny of Varietal Hybrids", of which the opening paragraphs read as follows:
The latest publication of Hugo de Vries: "Sur la loi de disjonction des hybrides," which through the courtesy of the author reached me yesterday, prompts me to make the following statement:
In my hybridisation experiments with varieties of maize and peas, I have come to the same results as de Vries, who experimented with varieties of many different kinds of plants, among them two varieties of maize. When I discovered the regularity of the phenomenon, and the explanation thereof- to which I shall return presently -the same thing happened to me which now seems to be happening to de Vries: I thought that I had found something new. But then I convinced myself that the Abbot Gregor Mendel in Brunn, had, during the sixties, not only obtained the same result through extensive experiments with peas, which lasted for many years, as did de Vries and I, but had also given exactly the same explanation, as far as that was possible in 1866. Today one has only to substitute "egg cell" or "egg nucleus" for "germinal cell" or germinal vesicle" and perhaps "generative nucleus" for "pollen cell". An identical result wad obtained by Mendel in several experiments with Phaseolus, and thus he suspected that the rules found might be applicable in many cases.
Mendel's paper, which although mentioned, is not properly appreciated in Focke's Die Pflanzen-Mischlinge, and which otherwise had hardly been noticed, is among the best that have ever been written about hybrids, in spite of some objections which one might raise with respect to matters of secondary importance, e.g. terminology.
At the time I did not consider it necessary to establish my priority for this "rediscovery" by a preliminary note, but rather decided to continue the experiments further. (Stern and Sherwood 1966: 119-120)
So Brannigan argued that "Mendel's revival in 1900 took place in the context of a priority dispute between Correns and de Vries and that this dispute led scientists to overlook the original intent of the earlier research" (Brannigan 1979: 422-423). He further suggests that the labeling of the discovery as "Mendel's laws" was a strategy to neutralize the dispute. "This", he claims (1981: 94) "is perhaps the single most important fact in the reification of Mendel as the founder of genetics."
To Brannigan, the case of Mendel's "rediscovery" is a good example of his social attributional model of discovery which he juxtaposes with mentalistic models. That is, instead of viewing discovery in terms of the creative genius of scientists, Brannigan (1981) argues that discovery should be treated as a process of social recognition which only later appears to be mentalistic or independent. Within this problematic, the great problems presented by scientific discovery are not simply who said, did, or "found" something first, or how several scientists sometimes almost simultaneously converge on a single theoretical model or technical procedure; the question is not how ideas come to mind, but how specific contributions come to be regarded as discoveries. As Brannigan (1979; 448) put it, "A theory of discovery should concern itself not with determining what makes discoveries happen, but with what makes certain happenings discoveries."
It would be difficult to disagree with the general thrust of Brannigan's view of discovery. But, should we accept his view that Mendel's laws and his representation as "the founding father" of genetics is largely an artifact of a priority dispute between Correns and de Vries and that this dispute led scientists to "overlook the original intent of the earlier research"? Certainly, one might think this to be plausible, for scientists are often only concerned with those who precede them in so much as they see in past work elements of what they take to be the truth. Looking at the past from their present perspective they often impose their own framework of understanding on the work in question irrespective of the intentions of the author. From this perspective all would agree that Mendel's work was superior to that of his contemporary hybridists. On this basis, for example, Zirkle, who did so much to show how Mendel's methodology was not as unorthodox as commonly assumed, still insisted that Mendel deserves the recognition he has received by geneticists:
To conclude, we may be certain that Mendel was acquainted with the work of Knight, of Sageret and of Gartner and probably also knew of Dzieron's hybrid ratio. In addition he had clues which led to the work of Seton and Goss. All of these contributions should have aided him in designing his experiments and have alerted him in what to look for. Of course his knowledge of this previous work would not detract from his own great accomplishments in the least. All of the earlier work together does not constitute Mendelism. Mendel's own experiments are so much more extensive and precise than those which went before that we are still justified in crediting him as the founder of a science. (Zirkle 1951: 103)
However, Brannigan's claim is questionable on several grounds. This suggestion seriously clashes with the fact that the issue of Mendel's intentions was addressed by William Bateson (1902, 1909), R.A. Fisher (1936) and many other scientists to the present day. The fact that scientists have shown such a remarkable interest in Mendel's "true intentions" deserves explanation. It is first necessary to highlight a second difficulty with Brannigan's suggestion: it implies that Mendel's intentions would be obvious had anyone bothered to discern them. (Callender (1988) makes similar assertions) Yet, as we have seen, despite the many attempts to reconstruct Mendel's thought process, there have always been, and continue to be, different opinions of Mendel's "real intentions".
Mendel kept no diary and wrote little about himself (for biographical information on Mendel see for example, Iltis 1932, Olby 1985). He published only two papers (Mendel 1866, 1870). The main source for reconstructing Mendel's thought process is his paper of 1866 entitled "Experiments in Plant Hybrids", a concise transcript of two reports given at the Brunn Natural History Society in 1865. The whole story of the development of the new theory is usually claimed to be given in these 44 printed pages. Scientific papers are not diaries. But is Mendel's own account a given to be taken at face value? The work of several historians and sociologists have shown that scientific papers commonly misrepresent the thought process that accompanied the work that is described in the paper. Scientific papers are often designed so as to give a veneer of objectivity and "matter of factness" to published claims. This obscures the intentions and biases of the author and the process by which results are produced. Mendel's paper is exemplary. His remarks concerning his experiments and the non-evolutionary views of the hybridist Gaertner illustrate the point. Conflicting interpretations of the following passage (in both the original German and in English translations) have been offered:
Gaertner, by the results of these transformation experiments, was led to oppose the opinion of those naturalists who dispute the stability of plant species and believe in a continuous evolution of vegetation. He perceives in the complete transformation of one species into another an indubitable proof that species are fixed within limits beyond which they cannot change. Although this opinion cannot be unconditionally accepted, we find on the other hand in Gartner's experiments a noteworthy confirmation of that supposition regarding variability of cultivated plants which has already been expressed. (translated by W. Bateson in Sinnot, Dunn, and Dobzhansky 1958, pp.442-443)
Does this statement mean that Mendel was an evolutionist or a non-evolutionist? R.A. Fisher (1936:118) stated: "It will be seen that Mendel expressly dissociates himself from Gaertner's opposition to evolution, pointing out on the one hand that Gaertner's own results are easily explained by the Mendelian theory of factors." Similarly Gavin de Beer (1964:208) commented: "This passage comes as near to the acceptance of the mutability of species as anyone could wish." Yet, Callender (1988:54) offers exactly the opposite interpretation: "If this statement is to be taken literally, as Mendel most assuredly intended it to be taken, then it says quite simply that he gave conditional acceptance to the view, expressed by Gaertner, that species are fixed within limits beyond which they cannot change. Nothing could be clearer." But surely anything could be clearer. We do not have to decide here which interpretation is the correct one. It is enough to recognize at this point that Mendel's literary style, his attempts to sound objective in his evaluation of Gaertner's views, his use of double negatives, obscures his own intentions. It is not surprising that there is no consensus about the meaning Mendel gave to his own experimental work.
Returning to Brannigan's suggestion, I am not trying to suggest that the priority dispute between de Vries, Correns and Tschermak was not important for the initial recognition accorded to Mendel. I would only protest against any tendency to reduce the significance of Mendel's experiments and his place as the founder of genetics to being an artifact of a priority dispute which supposedly led scientists away from examining Mendel's intentions. There is much more than this underlying the value scientists have attributed to Mendel's work. We need not one cause for understanding Mendel's place in the history of genetics, but several. Mendel and the meaning of his experiments have come to be clothed in various social and intellectual guises.
Any understanding of the significance of Mendel's experiments in biology would have to recognize the importance of "founding father mythologies" in the social and intellectual construction of science. The aggrandizement of past scientists through stories of their heroic insights may play an important role in defining and strengthening emergent scientific research traditions. Paul Forman (1969) has exposed various myths in scientists' accounts of the discovery of X-ray crystallography. He interpreted these myths as attempts to strengthen the tradition of X-ray crystallography by "tracing it to a higher, better, more supernatural reality of initial events." He argued (1969: 68) that "the traditional account may be regarded as a myth of origins, comparable to those which in 'primitive' societies recount the story of the original ancestor of a clan or tribe." Olby (1979) has suggested the same explanation for understanding the aggrandizement of Mendel in scientists' accounts of the origin of genetics. If this view be developed I suggest it would help us understand Mendel's prominent place in genetic discourse and culture.
At the most general level, Mendel's experiments are ladened with morality. The long neglect theme, portraying the discoverer as a creative genius clothed in monastic virtues pursuing the truth undauntedly on the lonely frontiers of knowledge, unappreciated by his contemporaries, has been important in keeping Mendel's experiments alive. Brannigan himself, following Barber (1962) has argued that one of the reasons why the Mendel case has been so poignant is because it has been presented as a tragedy which appeals to our sense of moral indignation. As Barber notes (1962, 540): "The mere assertion that scientists themselves sometimes resist scientific discovery clashes, of course, with the stereotype of the scientist as "the open-minded man." Brannigan (1979:453-454) compares Mendel's case to that of Galileo. "In both cases, great contributions went unrewarded by the local communities. In other words, the suppression of Galileo by the Church and the apparent obscurity of Mendel elicit a common moral reaction over the patent injustice experienced by each."
The element of morality is also embodied in another feature of the Mendel legend: the question of whether or not Mendel was honest in reporting his data as first raised by R.A. Fisher (1936). The claim that there was no deliberate falsification in Mendel's work has received a great deal of support from geneticists. At first glance such a debate might seem trivial. Who really cares if Mendel fudged some data? After all he was right. However, once we consider the important cultural role of "founding fathers" in defining groups, the intentions and motives of the celebrated originator becomes extremely important. It is not surprising that the interest in whether or not Mendel deliberately faked some of his data was first brought to great public attention at centennial celebrations of Mendel's paper and centennial symposiums of the genetics clan (See Dunn 1965:12; Iltis 1966:209; Olby 1966; Thoday 1966; Wright 1966:173-175; Beadle 1967:337-338).
The search for purity of motives in "founding fathers" is pervasive in the history of science. The reconstruction of the thought process of a creative genius has been central to the Darwin industry (see Shapin and Barnes 1979). What is a stake in this controversy is whether or not Darwin was in any way part of or responsible for the political and ideological uses of his theory. It is well known today that "evolution had been invoked to support all sorts of political and ideological positions from the most reactionary to the most progressive." (Young 1971: 185) Several writers have charged that Darwin was influenced by the socio-economic views of Thomas Malthus. Others argue that he was as much a Social Darwinist as his contemporaries who appealed to "nature" to legitimate their political views (Moore 1986). As Shapin and Barnes (1979: 127) have pointed out, "Darwin's defence" rests upon three assertions: "
The first is that of internal purity: Darwin's intentions and motives in writing the Origin were above reproach, and his personal beliefs in 1859 were innocent of "ideological" taint. The second is purity of ancestry: "influences upon the Origin were entirely wholesome and reputable, nothing "ideological" was gleaned from Malthus. The third assertion is purity of germ-plasm: nothing outward could properly be deduced from the theory in the Origin; truth does not blend with error; insofar as truth was used to justify social Darwinism, it was misused.
Shapin and Barnes (1979: 133) concluded that "Darwin's defence is far better staffed and funded than its opposition" but the more interesting question for us is: why has the trial been conducted at all? Shapin and Barnes (1979: 134) can only suggest an anthropological explanation:
The scientific discipline of evolutionary biology had its font and origin in the person of Charles Darwin and in the text of 1859. Darwin is a sacred totem by virtue of his "foundership" of modern biology: science is sacred, so must Darwin and his Book be sacred; both must be protected from contamination by the profane. As the author of the Origin he must himself be pure; his thought must be unmingled with wordly pollutions and incapable of satisfactorily blending or combining with the suspect formulations of social Darwinism. Thus, "influences" from the "profane" Malthus can only be the spiritual emanations of mathematics and genuine science, or nonessential stimuli or manners of speech. And implications for social Darwinism can only be misunderstandings.
Although this is a speculative suggestion, it has a great deal of merit in helping us to understand why the motives of so many "founding fathers" have been put to scrutiny.
It might not come as such a surprise that the recent claims that Mendel was not the founder of genetics, and that he did not make a major (though neglected) discovery have also been dismissed by biologists. Despite the arguments of some non-scientists, scientists themselves still insist on portraying Mendel as a "hidden genius" whose work was ignored until 1900. For example, in his celebrated book The Growth of Biological Thought, the evolutionist Ernst Mayr (1982:713) dismisses the view that Mendel belongs in the hybridist tradition. Instead, Mayr insists that Mendel was a true evolutionist and that:
As a student of Unger and of the problem of evolution, Mendel was concerned with single character differences and not, like the hybridizers, with species essence. To understand this fully is important for the interpretation of Mendel's work. It is totally misleading to say that Mendel's conceptual framework was that of the hybridizers. It is precisely the breaking away from the tradition of hybridizers that characterizes Mendel's thinking and constitutes one of his greatest contributions.
Mayr (1982:717-718) recognizes that "Olby and others" are right that
Mendel did not by a single stroke, create the whole modern theory of genetics. He did not have the theory of the gene, but neither did his rediscoverers... However, Mendel's various discoveries (segregation, constant ratios, independent assortment of characters), combined with new insights acquired between 1865 and 1900, led, one is tempted to say automatically, to the theory quite legitimately called Mendelian. (Mayr 1982: 717-718)
To Mayr, (1982: 725) this "by no means diminishes Mendel's greatness". On the contrary, by showing that Mendel's theory was not fully complete, Mayr argues, the work of Olby and others only make it easier to understand why it was ignored for 34 years.
The cultural importance of "founding fathers", and scientists' so-called "myths of origins", help us to understand why accounts of Mendel's discovery and neglect are repeated over and over again. However, scientists' stories about the long neglect of Mendel and his pea experiments do not simply reappear over and over again. They also change in such a way that the thoughts and motivations of Mendel are often altered; he is persistently undressed and redressed in new colours of allegiance. We have yet to explain one of the most striking features of the Mendel literature: the very diversity of "the long neglect" accounts. Any complete account of discovery and Mendel's prominent place in genetic culture, would have to recognize that scientists' accounts of history play various important roles in their knowledge making process. They surround experimental evidence, and constitute part of the art of persuasion in science (See Sapp, 1986, 1987, 1990). The stories about Mendel's discovery and neglect vary, and we need to know their specific rhetorical function in the constitution of scientific knowledge. For example, there is a similar story of discovery neglect and rediscovery concerning the work of Archibald Garrod in the origins of biochemical genetics . In this case, it seems to be clear that the construction of the story about the "long neglect" of Garrod was designed by some geneticists in the 1950s to support the truth of a specific model of genic control. According to this myth, the "truth" (a one-to one- relationship between genes and enzymes) like the discovery of the laws of inheritance, had been suggested several decades earlier, but given an unfair hearing (see Sapp, 1990). Similar neglect accounts in which scientists are held to have been given an unfair hearing are pervasive in science. One of the most recent is that of the German-American geneticist, Richard Goldschmidt constructed by Stephen J. Gould (see Dawkins 1988: 81-82, 231-41).
What is often at stake in scientists' reconstructions of Mendel's thought process is a definition of the concepts and/or movements that can be legitimately associated with the genetics tradition. Throughout the Twentieth Century the significance of Mendelian genetics has changed. For example, the first generation of geneticists viewed Mendelism to be in direct conflict with Darwinian selection theory. By the 1930s, Mendelism was held to be compatible with Darwinian selection theory. No doubt the meaning of many experiments can be and is continually renewed as science proceeds. However, it is not just the meaning scientists place on Mendel's experiments that change with the development of Mendelian genetics, the inferences as to the meaning Mendel himself placed on his experiments also changes accordingly.
The very fact that Mendel published so little, and that his motives are underdetermined in his papers, has helped his experiments to survive. Certainly, establishing the motives and intentions of scientists is a precarious business at the best of times but in few cases do we have to rely so much on logical reconstructions of a scientific paper, as we do in the case of Mendel. Mendel's experiments thus become a flexible resource, and as a "founding father" whose intentions are so important, he is adaptable indeed. In a sense, Mendel was lucky enough to please anyone who had an axe to grind. Mendel and his experiments function as a source around which each new generation of geneticists constructs its social and intellectual world of legitimate associations. The meaning of his experiments, what he actually "discovered", how the discovery was achieved, how and why it was ignored has been interpreted to support a great variety of debates in the history of genetic research. The significance of Mendel's experiments lies in the diverse ways in which commentators have constructed stories about them and used them in their knowledge making. The strength of these stories, I suggest, changes according to the power relations in the field of genetics and evolutionary biology.
The history of genetics research in the twentieth century is marked by various struggles among competing groups over the direction of, and approaches to, biological research. It is marked by conflicts between experimentalists (geneticists) and non-experimentalists (naturalists and statisticians) over whether or not evolution is continuous or discontinuous; and conflicts between experimentalists (embryologists and geneticists) over whether or not Mendelian genes controlled only superficial characteristics of the organism. We can find all these issues reflected in geneticists' accounts of Mendel's neglect. To follow scientists' reconstructions of Mendel's thought and the reasons for his neglect by the 19th century is to follow some of the central controversies in the development of genetic research in the twentieth century.
The idea that everyone saw in Mendel's experiments what they wanted to see is not a new interpretation. In fact, it was first suggested by R.A. Fisher (1936) in a noted paper, "Has Mendel's Work Been Rediscovered?". This was the first detailed attempt to reconstruct Mendel's thought process. By following the main lines of argument in Fisher's paper, we can begin to unravel the reasons for some of the diverse interpretations of Mendel's experiments and examine the wealth of issues that have kept Mendel's experiments alive and vibrant. As we shall see, the specific representations of his experiments and intentions by biologists often reflect divergent and conflicting interests in the field of heredity and evolutionary theory. We will begin with the particular way in which Fisher reconstructs Mendel to suit his own particular interests.
2. Appropriating the Founding Father
Fisher's reconstruction of Mendel's thought process came at a time when Darwinian theory was becoming intimately allied with Mendelian genetic principles. Fisher himself had played a leading role in this synthesis. In part, Fisher's paper represented an attempt to understand the famous dispute between the biometricians (statisticians) and the Mendelians (experimentalists). Conflicts between statisticians and Mendelian geneticists emerged at the turn of the century, soon after Mendel's laws were "re-discovered" (see Provine 1971; Kevles 1980; Mackenzie 1981). The theoretical element of the dispute revolved around the question of whether evolution was continuous or discontinuous - whether new species emerged slowly by natural selection, or quickly through large mutations, with natural selection playing only a negative role in selecting out those new species or mutants which could not survive.
Biometricians, led by Karl Pearson and W.F.L. Weldon in England, saw themselves as Darwinians. They supported continuous evolution. Mendelians, led by William Bateson were non-Darwinians and supported discontinuous evolution. The dispute raged on in private correspondence and in published journals throughout the first decade of the century. Bateson found it "impossible to believe" that biometricians had "made an honest attempt to face the facts." He doubted that they were "acting in good faith as genuine seekers of the truth." (quoted in Kevles 1980: 442). Weldon (1901) for his part, attempted to test the validity of Mendelism by subjecting Mendel's results to statistical tests. He did not claim that Mendel's results were statistically too good to be true, but doubted the possibility of reproducing Mendel's results with further pea experiments. Weldon concluded his critique with the remarks that Mendel was "either a black liar or a wonderful man." He remarked to Pearson, in 1901, "If only one could know whether the whole thing is not a dammed lie!" (quoted in Kevles 1980: 445)
But there was more to the debate than a theoretical discussion about evolution. Both Mendelians and biometricians were struggling to dominate the field; both based their work on different methods as well as different theories. Methodological issues became a principal stake in this controversy. Which methods, those of the experimentalist or those of the statistician were most appropriate for biological, that is evolutionary problems? Geneticists, using experimentation as their polemical tool attempted to exclude biometricians from the field by denying the legitimacy of purely statistical approaches to heredity and evolution. The views of Wilhelm Johannsen - who provided the central terms of genetics: "genotype", "phenotype", and "gene"- were representative of those experimentalists who supported discontinuous evolution:
Certainly, medical and biological statisticians have in modern times been able to make elaborate statements of great interest for insurance purposes, for the "eugenics-movement" and so on. But no profound insight into the biological problem of heredity can be gained on this basis. (Johannsen 1911: 130)
Thus, the non-Darwinian geneticists attempted to exclude Darwinian statisticians from the field. The dispute between the biometricians and Mendelians came to a head in England by 1905. Bateson was judged to be the victor (see Provine 1971).
However, by the 1920s and 1930s statisticians began to re-establish their authority in the field. They gained their legitimacy primarily from the statistical studies of populations led by the contributions of Fisher, Haldane and Wright. They were central architects of what Julian Huxley in 1942 called the "modern synthesis". The evolutionary synthesis of the 1930s and 1940s was based upon Mendelian gene recombination, mutation, and Darwinian selection theory. Evolution according to this theory was continuous after all; Bateson and the first generation of geneticists are judged to be wrong in allying Mendelism with non-Darwinian views of discontinuous evolution.
Fisher's paper of 1936 fits squarely within this theoretical shift. One can understand it as an attempt to put the last nail in the coffin of the controversy. Central to his paper is a interpretation of Mendel's motives and theoretical views. The principal stake in Fisher's paper is an historical dispute over Mendel's attitude towards Darwinian natural selection. Bateson had cast Mendel as a non-Darwinian ally in his struggle against Darwinian biometricians. Fisher, on the other hand, attempted to recast the "founding father", Mendel, as a good Darwinian. Both Bateson and Fisher superimposed their own motivations and the context of their own work onto those of Mendel and his times.
The main thrust of Fisher's criticisms was aimed at Bateson. Fisher used Bateson as a scapegoat for the heated controversy between Darwinians and Mendelians. He charged that Bateson had deliberately intended to deceive scientists by allying Mendel and Mendelism with non-Darwinian views and by fabricating and distorting history to suit his interest:
It cannot be denied that Bateson's interest in the rediscovery was that of a zealous partisan. We must ascribe to him two elements in the legend which seem to have no other foundation: (1) The belief that Darwin's influence was responsible for the neglect of Mendel's work, and of all experimentation with similar aims; and (2) the belief that Mendel was hostile to Darwin's theories, and fancied that his work controverted them. (Fisher 1936: 116)
As mentioned, Bateson and the first generation of Mendelian geneticists were in struggle with non-experimentalists, many of whom believed that Mendelism had little to do with the origin of species. Bateson, who actively promoted genetics, frequently mocked the integrity of alternative and conflicting approaches to the study of heredity and evolution. He claimed that alternative approaches and views of evolution were based on mere speculative theorizing which he believed stood in the way of sound experimental investigations of heredity. As Bateson (1914: 293) wrote:
Naturalists may still be found expounding teleological systems which would have delighted Dr. Pangloss himself, but at the present time few are misled. The student of genetics knows that the time for the development of theory is not yet. He would rather stick to the seed pan and the incubator.
Appropriating Mendel, Bateson immediately began to tell stories in his scientific papers and books about Mendel's intentions and about how Mendel's work was neglected. Bateson and Saunders (1902:6) suggested that the principle of natural selection " had almost completely distracted the minds of naturalists from the practical study of evolution. The labours of hybridists were believed to have led to confusion and inconsistency, and no one heeded them anymore."
In his book, Mendel's Principles of Heredity, Bateson claimed that like himself, Mendel had worked in virtual conflict with non-experimentalists and Darwinians and that this was partly responsible for Mendel's "neglect" for 35 years. Thus Bateson (1909: 2) wrote:
While the experimental study of the species problem was in full activity the Darwinian writings appeared. Evolution, from being an unsupported hypothesis, was at length shown to be so plainly deducible from ordinary experience that the reality of the process was no longer doubtful. With the triumph of the evolutionary idea curiosity as to the significance of specific differences was satisfied. The Origin was published in 1859. During the following decade, while the new views were on trial, the experimental breeders continued their work, but before 1870 the field was practically abandoned.
The suggestion that Darwin's influence was partly responsible for the neglect of Mendel's work was promoted by other geneticists who had pioneered the development of Mendelian analysis at a time when many biologists believed it was a minor curiosity with little bearing on the grand problems of evolution. For example, L.C. Dunn, who had been engaged in such polemics during the second decade of the century, tended to share Bateson's interpretation of Mendel's neglect:
There is probably some truth to the explanation often offered, that Mendel was dealing with the minor tactics of evolution, and only indirectly at that, at a time when biologists had their thoughts and ambitions focused on the kind of grand strategy represented by the Origin of Species (L.C.Dunn 1965:18)
But Bateson went further than Dunn. He not only suggested that Mendel was in virtual struggle with naturalists, he also imposed a non-Darwinian motive on Mendel:
With the views of Darwin which were at that time coming into prominence Mendel did not find himself in full agreement, and he embarked on his experiments with peas, which as we know he continued for eight years. (Bateson 1909: 311)
"Had Mendel's work come into the hands of Darwin" Bateson (1909:316) declared, "it is not too much to say that the history of the development of evolutionary philosophy would have been very different from that which we have witnessed."
Fisher strongly opposed Bateson's interpretation and claimed it was self-interested and held no truth value. Fisher (1936: 117) argued:
Bateson's eagerness to exploit Mendel's discovery in his feud with the theory of Natural Selection shows itself again in his misrepresentation of Mendel's own views. Although he was in fact not among those responsible for the rediscovery, his advocacy created so strong an impression that he is still sometimes so credited.
Fisher, who 'knew' that Mendelism was not opposed to natural selection, believed that Mendel also knew that his work was allied with Darwinism. Those who believed that natural selection was the principal driving force in evolution could share both Mendel and Darwin as common intellectual ancestors.
When reconstructing Mendel's thought process, Fisher claimed that Mendel's experimental program could only be made intelligible on the basis that Mendel worked squarely within a Darwinian framework. For example, he claimed that in Mendel's day most hybridists crossed different species. They believed that species did not evolve and that they possessed essential qualities, specific, natures or "essences". They were concerned with crosses between species to investigate the ways in which the forms of the hybrid reflected the parental "essences". Mendel's approach, Fisher reasoned conflicted with this: he crossed closely allied varieties not different species. This suggested to Fisher not only that Mendel was an evolutionist, but that his work was actually carried out within a Darwinian framework. Thus, Fisher (1936: 117) wrote: "It's a consequence of Darwin's doctrine, that the nature of hereditary differences between species can be elucidated by studying heredity in crosses within species." The issue of whether the genetic elements responsible for differences between species could be detected by crossing individuals within a species was a highly contentious one during the first half of the twentieth century. Many biologists who opposed the all exclusive role of genes in evolution argued that Mendelian genetics applied only to trivial characteristics: eye colour, hair colour, tail length etc, and did not account for species differences. They maintained that "fundamental" characteristics of the organism which distinguished higher taxonomic groups (macro-evolution) lay beyond the Mendelian- chromosome theory and Darwinian selection theory (see Sapp, 1986, 1987). Fisher, on the other hand, suggested that Mendel himself would have opposed such views as evidenced, he claimed, by Mendel's crossing of varieties rather than species. Moreover, Fisher (1936:118) argued, Mendel had claimed that his "laws of inheritance" formed a necessary basis for understanding the evolutionary process. "Had he considered that his results were in any degree antagonistic to the theory of selection it would have been easy for him to say this also."
If this be the correct interpretation of Mendel's experimental program, then how did it go undetected for so long? Fisher (1936: 137) concluded his attempts to reconstruct Mendel as a good Darwinian by raising two issues in this regard. First, he claimed (like Brannigan and Callender later) that Mendel's opinions had been misrepresented because his work was not examined with sufficient care. Writers relied on accounts of others. But as Fisher remarked "there is no substitute for a careful, or even meticulous, examination of all original papers purporting to establish new facts." Second, Fisher suggested that biologists before him had imposed their own meanings on the work of Mendel. Their interpretations were influenced by the theory of their times:
Each generation, perhaps found in Mendel's paper only what it expected to find; in the first period a repetition of the hybridization results commonly reported, in the second a discovery in inheritance supposedly difficult to reconcile with continuous evolution. Each generation, therefore, ignored what did not confirm its own expectations. (Fisher 1936: 137)
Indeed, the reading of scientific papers, like the construction of original scientific data, is not a straightforward affair. Meaning is not embedded in raw observations. It is bestowed upon the data by the intentions of the observer. Nor is a unique timeless meaning embedded in scientific papers reporting original data. It is often superimposed onto such papers. As Fisher suggests, when one reads a scientific paper one does so with theoretical expectations in mind. In his view, the biases of others were obstacles to the recognition of Mendel's discovery. However, once we recognize that all scientists have such biases, the issue of discovery is not one of unveiling certain truths which lay hidden in nature, or in past scientific papers. It is a matter of constructing the discovery.
It is striking that Fisher excluded his own interpretation from any biases. Many of his claims have been challenged. It would not be difficult to show some of the ways in which Fisher himself shaped the evidence from Mendel's paper in order to impose a Darwinian framework on him. In effect, this was done by Gasking (1959). Gasking was the first non-scientists to offer a detailed account dealing with the long existing question: "Why was Mendel's work ignored?" She (1959:68) argued that although Mendel knew of the controversy surrounding the origin of species, his experiments were not directly concerned with it at all. Instead, she claimed (1959: 68) that "he was from the outset looking for laws governing the inheritance of particular characteristics."
Like Fisher, Gasking based her argument on a logical reconstruction of Mendel's experiments. Gasking did not refer to Fisher's paper of 1936 and it is unlikely that she had read it. However, in effect, she debunked one of Fisher's arguments that Mendel's protocols can only be understood if he were a Darwinian. First, she pointed out that Mendel used both varieties and species in his experiments. Fisher was only telling a half-truth. According to Gasking (1959: 68), Mendel was simply "indifferent whether his crosses were between species or only between varieties." But, this was not because he was a proponent of Darwinian evolution, as Fisher suggested. In her view, "Mendel's thinking was more like a farmer's than a biologist's." Gasking explained that unlike hybridists of Mendel's day who were concerned with "specific natures" or "essences" of a species. "Farmers and stock-breeders", Gasking explained, "have a different problem."
They are concerned not with the complete nature of a species, but rather with a particular property: they want cattle of larger size, beets with a higher sugar content, or whatever it may be, and the importance of inheritance for them lies in the results of crossing plants or animals having this particular property in different forms and degrees, Mendel's interest in inheritance was similar, and so differed fundamentally from that of other biologists. (Gasking 1959:61)
Gasking's paper is representative of the "long neglect" or "rediscovery accounts" of Mendel's experiments, an approach that should be abandoned in favour of an "anthropological" and sociological approach to understanding the power of Mendel's experiments. As I have suggested above, this alternative perspective helps us to understand still another central aspect of Mendel's experiments that has been so poignant among biologists: the question of whether Mendel's reported results were faked.
3. Reconstructing Mendel's Data
Since Fisher wrote his paper, "Has Mendel been Rediscovered?" a great deal of attention has been given to the question of whether or not Mendel deliberately fudged his data. In view of Mendel's stature in genetic culture, and the defence he subsequently received by geneticists, it might be questioned why R.A. Fisher, a Mendelian himself, would make such a charge in the first place. After all, fraud charges are often made to discredit an individual and/or competing theory. It was in the course of constructing Mendel as a good Darwinian that Fisher made the claim that Mendel's results were too good to be true, and calculated that in the over-all results one would expect a fit as good as Mendel reported once in 30,000 repetitions. However, this charge was not meant to discredit Mendel; it was meant to celebrate his power of abstract reasoning. Fisher (1936, p. 123) argued that Mendel had his laws in mind before he did his experiments:
In 1930, as a result of a study of the development of Darwin's ideas, I pointed out that the modern genetic system, apart from such special features as dominance and linkage, could have been inferred by any abstract thinker in the middle of the nineteenth century if he were led to postulate that inheritance was particulate, that the germinal material was structural, and that the contributions of the two parents were equivalent. I had no idea that Mendel had arrived at his discovery in this way. From an examination of Mendel's work it now appears not improbable that he did so and that his ready assumption of the equivalence of the gametes was a potent factor in leading him to his theory. In this way his experimental programme becomes intelligible as a carefully planned demonstration of his conclusions.
In Fisher's account, the claim that Mendel's data was too good to be true provides testimony to his claim that Mendel had his ideas in mind before doing his experiments. Mendel was a thinker not a tinker. But, did he cook his results to suit his theory? Fisher entertained three possibilities to account for Mendel's results: 1) that Mendel was lucky; 2) that he unconsciously biased the results, and 3) that he consciously biased the results in favour of his theory. Fisher ruled out the first two possibilities as providing inadequate accounts and concluded a conscious bias of "fudging the data". However, he did not rest the responsibility on Mendel. Instead of questioning Mendel's integrity, he suggested that possibly "Mendel was deceived by an assistant who knew too well what was expected." (Fisher 1936: 132)
Fisher's analysis of Mendel's data raises another set of issues for methodological reflection: this time about observer bias, the theory- ladenness of observations, and whether or not the validity of experimental results could be tested statistically. Indeed, although Fisher's reconstruction of Mendel's thought process represented part of the process of closing the dispute between Mendelism and Darwinism, at the methodological level the conflict between statistical and experimental modes of reasoning continued. Geneticists who subsequently addressed Fisher's claims found it is necessary to consider these methodological differences when attempting to understand the strength of statistical critiques of experimental results. Some of the difficulties to be encountered are well illustrated by a critique of Fisher's paper by the celebrated microbial geneticist George Beadle in the proceedings of the "Mendel Centennial Symposium" sponsored by the Genetics Society of America in 1965. Beadle charged that Fisher's reconstruction of Mendel's methods was incomplete and he explored the phenomenon of unconscious bias to account for Mendel's results. He claimed that Fisher had considered one kind of bias only, due to "misclassification" of some hereditary variations, for example, "a shriveled round pea scored as "unwrinkled". Beadle remarked, "As every experimenter in genetics knows, some classifications are difficult and may easily be unconsciously biased in favour of a preconceived hypothesis." (Beadle 1967:338). Beadle himself was personally sensitive to this source of error, for as he recalled:
I once discovered a loose genetic linkage in maize between floury endosperm and a second endosperm character known to be on chromosome 9, a linkage that I subsequently concluded was the result of my "wanting" to find it. The floury character is often difficult to score, and I believe I unconsciously put the doubtful ones in the piles that would suggest linkage.
However, Beadle was careful to protect his own credibility and added, "Fortunately, I recognized the possibility of this kind of error in time to withdraw a manuscript I had submitted for publication."
Observer bias in selecting and sorting data is indeed a serious obstacle for those who claim objective status for their experimental results. However, observer bias in selecting data in genetic analysis is only one difficulty. Beadle discussed a second problem resulting from the theory-ladenness of observations: how much data to include in a scientific paper and how an experimenter knows when the experiment is over. He suggested that it was entirely possible that Mendel stopped counting when he obtained results close to expectation. This possibility was also suggested by Dunn (1965) and Olby (1966). Beadle (1967: 338) explained:
As he [Fisher] points out, Mendel clearly had his hypothesis in mind before completing all his work and therefore rejected certain numerical ratios. It is also clear, as Fisher deduces, that Mendel did not classify all the pea plants and seeds he grew. Presumably he classified enough to convince himself that the result was as expected. It is perfectly natural under these circumstances to keep running totals as counts are made. If, then, one stops when the ratio "looks good", statistically the result will be biased in favor of the hypothesis. A seemingly "bad" fit may be perfectly plausible statistically, but one may not think so and add more data to see if it improves, thereby raising interesting questions, some mathematical and some psychological.
What is of concern to us is not if Beadle's remarks actually account for Mendel's particular results, but the methodological issues they raise. The last two sentences above are significant in this regard: What data looks "good" to the experimentalist, looks "bad" for the statistician and vice versa. There seems to be a methodological incommensurability concerning the nature of statistical and experimental modes of reasoning. This might be called the "experimentalist- statistician paradox". The idea is that from a statistical point of view, the geneticist should not provide "too much data" and have his or her results come too close to the theoretical expectations, for the closer they come to the "truth" the less true they will appear to be. This is a strange paradox indeed, and is based on faulty reasoning. The reason why data are considered to be less true the closer they reach theoretical expectations is based on the idea that the geneticists should be studying a random sample. It assumes that experiments should be carried out independently of the law or theory the observer is using for explanation. In other words, it appeals to naive empiricism and ignores the theory-ladenness of observations. The theory itself informs the experimenter about what kind of experiment to perform, what kind of phenomena to examine, and how results are to be understood; it also tells the experimenter when the experiment is over. This last issue is at the heart of Beadle's suggestion that Mendel simply stopped counting when he obtained the results expected.
What liberties scientists are "allowed" to take in selecting positive data and omitting conflicting or "messy" data from their reports is not defined by any timeless method. It is a matter of negotiation. It is acquired socially: scientists make judgments about what fellow scientists might expect in the way of methods, data, and standards, in order to be convinced. What counts as good evidence may be more or less well-defined after a new discipline or speciality is formed, but at revolutionary stages in science, when new theories and techniques are being put forward, when standards have yet to be negotiated, scientists have less an idea of what others may expect to be competent and convincing. Statistical criticisms were weak and could be easily trivialized as much as they ignored various aspects of the experimental process: the conscious and unconscious biases of geneticists in selecting certain phenomena to investigate and certain data to report. One could not evaluate the validity of Mendel's experimental claims on statistical grounds alone. Those who were accomplished in both statistics and and genetic experimentation such as Sewall Wright recognized the limitations of statistical criticisms. As Wright (1966: 173-74) remarked:
I do not think that Fisher allows enough for the cumulative effect on [Chi squared] of a slight subconscious tendency to favour the expected result in making tallies. Mendel was the first to count segregants at all. It is rather too much to expect that he would be aware of the precautions now known to be necessary for completely objective data.... Checking of counts that one does not like, but not of others, can lead to systematic bias toward agreement. I doubt whether there are many geneticists even now whose data, if extensive, would stand up wholly satisfactorily under the [Chi Squared] test.
4. The Rhetorical Nature of Scientific Papers
Fisher's paper of 1936 forces us to examine still another aspect of the experimental process - the extent to which published experimental reports can be taken as literal accounts of how scientists generate and interpret their data. This issue was raised by Bateson and Fisher when attempting to understand Mendel's conduct and determine the liberties he may have taken. Contrary to what is generally believed, Fisher was not the first to question the authenticity of Mendel's reported experimental results. Although it has been ignored by commentators who have examined Fisher's statistical criticisms of Mendel, Bateson's comments, raised the possibility that all of Mendel's "experiments" were fictitious. He suggested that Mendel could not have had the varieties of plants he described.
Bateson (1909: 350) questioned the authenticity of Mendel's celebrated experiments in a footnote to a passage in the translation of Mendel's experiments he used in his book, Mendel's Principles of Heredity. Mendel, after describing his first seven experiments, opened his subsequent section with the following claim: "In the experiments described above plants were used which differed only in one essential character." Bateson commented:
This statement of Mendel's in the light of present knowledge is open to some misconception. Though his work makes it evident that such varieties may exist, it is very unlikely that Mendel could have had seven pairs of varieties such that the members of each pair differed from each other in only one considerable character.
Fisher fully realized the weight of this criticism. One would expect that some or all of the crosses would have involved more than one contrasting pair of characters. Fisher believed that Mendel meant his reports to be taken literally. In response to Bateson's remarks, he offered two possibilities to account for Mendel's statement. Both involved how Mendel wrote up his reports and what he regarded as an "experiment". The first possibility was that: "He might, for each cross, have chosen arbitrarily one factor, for which that particular cross was regarded as an experiment, and ignored the other factors." (Fisher 1936: 119) Although this way of analyzing crosses might seem to be wasteful of data, Fisher claimed that Mendel, in fact, "left uncounted, or at least unpublished, far more material than appears in his paper." In other words, he published only enough data that he believed would be sufficient to convince readers of his theory. The second possibility was that: "He might have scored each progeny in all the factors segregating, assembled the data for each factor from the different crosses in which it was involved, and reported the results for each factor as a single experiment." (Fisher 1936: 119) This, Fisher claimed, is what most geneticists would take, unless they were discussing either linkage or multifactoral interaction.
On the other hand, Bateson's intimation that Mendel's "experiments" were fictitious remained a possibility. As Fisher noted, Mendel did not give summaries of the aggregate frequencies from different experiments. This conduct would be easily intelligible if the "experiments" reported in the paper were fictitious, being in reality themselves such summaries. This kind of over-simplification is often used when teachers illustrate principles to students in a lecture. Fisher (1936: 119) continued:
Mendel's paper is, as has been frequently noted, a model in respect of the order and lucidity with which the successive relevant facts are presented, and such orderly presentation would be much facilitated had the author felt himself at liberty to ignore the particular crosses and years to which the plants contributing to any special result might belong. Mendel was an experienced and successful teacher, and might have adopted a style of presentation suitable for the lecture-room without feeling under any obligation to complicate his story by unessential details. The style of presentation with its conventional simplifications, represents, as is well known a tradition far more ancient among scientific writers than the more literary narratives in which experiments are now habitually presented. Models of the former would certainly be more readily accessible to Mendel than of the later.
It is difficult to know exactly what Fisher meant by the tradition of "ancient" scientific writers. However, one can easily challenge any sharp distinction between what Fisher called the "simplifications" of "ancient" scientific writers, and those "more literary" accounts of modern scientists. In effect, this has been done to some degree by Peter Medawar who in 1963 posed the question: "Is the Scientific Paper a Fraud?" In raising this question Medawar did not mean that the scientific paper misrepresents "facts", nor that the interpretations found in a scientific paper "are wrong or deliberately mistaken". What he meant was that "the scientific paper may be a fraud because it misrepresents the thought process that accompanied or gave rise to the work that is described in the paper." (Medawar 1963: 377)
Medawar was perhaps the first to emphasize that "The scientific paper in its orthodox form does embody a totally mistaken conception, even a travesty, of the nature of scientific thought." The structure of the "orthodox scientific paper" itself Medawar argued, is telling in this regard. He described the structure of the typical scientific paper in the biological sciences as follows:
First, there's a section called the `introduction' in which you merely describe the general field in which your scientific talents are going to be exercised, followed by a section called `previous work' in which you concede, more or less graciously, that others have dimly groped towards the fundamental truths that you are now about to expound. Then a section on `methods' - that's O.K. Then comes the section called `results'. The section called `results' consists of a stream of factual information in which it's considered extremely bad form to discuss the significance of the results you're getting. You have to pretend that your mind is, so to speak, a virgin receptacle, an empty vessel, for information which floods into it from the external world for no reason which you yourself have revealed. You reserve all appraisal of the scientific evidence until the `discussion' section, and in the discussion you adopt the ludicrous pretence of asking yourself if the information you've collected actually means anything; of asking yourself if any general truths are going to emerge from the contemplation of all the evidence you branished in the section called `results'.
The above description is somewhat of an exaggeration, for certainly many scientific papers do not follow this structure. But we can agree with Medawar that there is "more than a mere element of truth in it." "The conception under-lying this style of scientific writing is that scientific discovery is an inductive process." (Medawar 1963: 377) In its crudest form induction implies that scientific discovery, or the formulation of scientific theory begins with the "neutral" evidence of the senses. The scientific paper gives the illusion that discovery begins with simple unbiased, unprejudiced, naive and innocent observation. Out of this unbridled evidence and tabulation of facts orderly generalizations emerge, crystallize or at least gel. Yet scientists know full well that discoveries do not emerge and gel in this way. They know what meaning to place on their results before they conduct their experiments. Indeed, it is their anticipation of results that informs them of what experiments to perform, what phenomena to examine, and what data to report. Medawar traces the inductive structure often framing modern scientific papers to the 19th century writing of the philosopher John Stuart Mill. However, it would be naive to believe that scientists are the dupes of philosophers. It is also wrong to suggest that "the scientific paper" is a fraud. "The scientific paper" is not a fraud; it is rhetoric. The structure of the narrative of the scientific paper plays an important persuasive role in science. First, it is important to remember that scientific work is steeped in the biases of two cultures: the larger culture in which science is allowed to persist, and the scientific culture itself. Scientists' belief in theories, the experiments and observations they make and report are often influenced by forces arising from both. In larger culture scientists have maintained their legitimacy in part by appealing to their "objectivity". The literary style of the scientific paper is designed to protect scientists' interests as purveyors of truth and to maintain public support.
The structure of the scientific paper plays a similar rhetorical role within the scientific culture. Shapin (1984) gives a detailed study of an early attempt to construct conventions for writing scientific papers. He shows that the 17th century experimentalist Robert Boyle set out rules to distinguish authenticated scientific knowledge from mere belief. This was done, in part, by what Shapin calls "the literary technology of virtual witnessing." This "literary technology by means of which the phenomena produced ...were made known to those who were not direct witnesses", involved providing protocols for experiments, recounting unsuccessful experiments and displaying humility so as not to look self-interested and untrustworthy, citing other writers not as judges but as witnesses to attest matters of fact, etc. Boyle's literary technics would give a veneer of objectivity and "matter of factness" to published scientific claims. But this often obscures the intentions of the author and the process by which results are produced. Indeed, often the method sections of scientific papers are imprecise. Medawar's deconstruction of "the scientific paper" is incomplete in this regard. Seemingly trivial, but yet vital information concerning procedures are often left out of scientific papers (see for example, Collins 1985). As a result, as the case of Mendel illustrates, interpretations of a scientist's conduct and procedures often involve considerable speculation and conjecture. When commenting on Mendel's paper one writer remarked. "All geneticists admitted that it was written so perfectly that we could not - not even at present- put it down more properly." (Nemec 1965:13) Yet, it was this very "perfection" that has made Mendel's conduct so difficult to ascertain.
5. Concluding remarks
Mendel's "Experiments on Plant Hybrids" have been shrouded in various myths about individual discovery and social neglect. The central point is not to debunk these myths and dismiss them, but to reveal them, study them and understand how they have been constructed, how they have persisted and how they have been altered since the turn of the century. The prominent place of Mendel's experiments in scientific culture is based on the strengths of these myths, the very diversity of the reconstructions of his thought process, and his role as the founding father of genetics. As with all founding fathers, reconstructing the experiment has been closely intertwined with reconstructing the intentions of the experimenter. Mendel has been cast as an ideal type of scientist wrapped in monastic and vocational virtues. Yet, the moral element of the Mendel legend is not the only thing that has captured scientists' interests. There is much more to the oft-repeated accounts of Mendel's neglect and the reconstruction of his thought process than a construction of an exemplar of scientific virtue- a representation of a scientific ideal. To discard the stories about Mendel's discovery and subsequent neglect as simply moral tales would be to ignore the important rhetorical role of Mendel's experiments in the construction of scientific knowledge.
Since the emergence of genetics, Mendel has become a cultural resource to assert the truth about what it means, not just to be a good scientist, a geneticist, but what Mendelian genetics implies. The divergent accounts of Mendel's neglect reflect the often conflicting social and intellectual interests of Mendel's commentators. To understand geneticists' reconstructions of Mendel's intentions is to understand the divergent and sometimes conflicting definitions of what Mendelian genetics signifies or connotes. The specificity of the accounts themselves is generated as part of the repertoire of rhetorical tools scientists have at their disposal when defending their social and intellectual positions in science. Geneticists' reconstructions of Mendel's true intentions are used to buttress conflicting claims about what concepts can be legitimately associated with Mendelism (continuous or discontinuous evolution for example). We have seen how Bateson and Fisher constructed Mendel and the reasons for his neglect to suit their own intellectual struggles over evolutionary theory. And this same pattern has been repeated over and over again. Representing the foundations of genetics, Mendel's experimental results are used by geneticists to discuss what is legitimate experimental practice, to reflect upon the unconscious biases of experimentalists, and the procedures by which experimental claims can be evaluated. In short, Mendel's experiments are a meeting place where scientists discuss the definition of science itself.
(This article originally appeared in Experimental Inquiries, edited by H. E. Le Grand, (Kluwer Academic Publishers, 1990), pp. 137-166. It appears at MendelWeb, for non-commercial educational use only, with the kind permission of the author and Kluwer. Although you are welcome to download this text, please do not reproduce it without the permission of the author and Kluwer Academic Publishing.)