Journal of the History of Biology (2010) 43:809–811 DOI 10.1007/s10739-010-9262-4
Ó Springer 2010
Book Review
Evelyn Fox Keller, The Mirage of a Space Between Nature and Nurture (Durham NC: Duke University Press, 2010), 107 pp., illus., $64.95, $18.95 paper. ‘‘Unless it is well defined,’’ sang Pete Townshend, ‘‘you just have to be resigned, you’re crashing by design.’’ Such is the message from Evelyn Fox Keller when we speak of ‘‘nature and nurture.’’ These central terms are hopelessly ill-defined in our debates about genetics leading to the bizarre situation of everyone simultaneously agreeing and disagreeing with one another. Our discussions crash by design. Keller is certainly not the first to note that debates about nature and nurture in a host of fields, particularly fields that touch on the scientific analysis of human genetics, have a ritualistic form. The set-piece looks something like this: Your own position is the one that fully embraces the up-to-date view that the conflict between nature and nurture is false. It is your opponent who is stuck in the wrong-headed opposition of nature and nurture and they need to accept your scientific position in order to move beyond their outmoded belief of the nature/nurture split. The problem is that it doesn’t really matter which side of a current scientific debate you are on when you make this claim: both behavioral geneticists and their opponents, for example, claim they are the ones who have moved beyond the false nature/nurture dichotomy. We find ourselves in this unhappy situation, Keller argues, because the language we use when we talk about genetics is itself confused; ‘‘An important source of confusion lies deep in the language of genetics,’’ she claims (p. 43). One example of the confusion is the word, ‘‘heritability.’’ This term, as Keller notes, is polysemous (capable of more than one denotative meaning). In the technical literature it refers to an analysis of variation of a given trait within a population. In everyday usage, it simply means something an offspring inherits from a parent. The difference between the two terms is really a host of differences. In the technical sense, heritability refers to a characteristic of a population, in everyday usage it refers to a characteristic of an individual. In the technical sense it refers to a measure of differences between traits; in everyday usage it refers to what causes a trait itself.
810
BOOK REVIEW
At this point, those familiar with these sorts of issue are undoubtedly growing impatient, ‘‘We know all this,’’ they might be thinking, ‘‘do we really need another book on it?’’ I think we do and one good reason is that while we all acknowledge the polysemy of terms in principle, it is very hard to keep them separate in practice. One of the great virtues of Keller’s book is that she notes that it is very, very difficult to keep the two separate usages clear, even by people who should know better and pride themselves on clear presentation. Thus we find philosopher of science, Neven Sesardic unable to keep the difference between ‘‘the causal strength of genetic influences on phenotypic differences’’ and ‘‘genetic determination of traits’’ separate in his writings (p. 41). It gets worse. ‘‘A similar confounding of the etiology of traits with that of trait differences,’’ Keller shows, ‘‘pervades virtually all of the current literature of medical genetics’’ (p. 45). Though all acknowledge the mistake, it seems, all commit it nonetheless. Keller’s book is valuable because it provides a crisp and articulate statement of the many confusions that pervade our talk of genetics, particularly human genetics. It could be used in both undergraduate and graduate classes that touch on these issues. Moreover, because Keller’s focus is on the problems of the language of genetics itself rather than on their instantiation in a particular controversy it brings clearly into focus the underlying problem that cuts across a number of controversies. The book should be taken as a summary of the issues and an agenda for how we proceed from here. As historians of biology, we can take Keller as providing us with a clear language for researching unclear controversies. As Keller writes, ‘‘Authors and readers alike routinely slide from one meaning [of heritability] to the other, wreaking havoc on the ways in which legitimate scientific measurements are interpreted’’ (p. 59). Rhetoricians who write on polysemy give us a vocabulary to explore the different ways it could be invoked. A historian could read a controversy to discover if the polysemy results from authorial intent; authors could be employing ‘‘strategic ambiguity’’ in order to simultaneously enroll both meanings of the term. Conversely, a historian could discover if readers were employing ‘‘resistive reading’’ to read a polysemous term against authorial intent. Finally, a historian could read a controversy hermeneutically; aware that the polysemy could be embedded in the situation in a number of ways (for more on the subtlety of polysemy see Leah Ceccarelli, ‘‘Polysemy: Multiple Meanings in Rhetorical Criticism,’’ Quarterly Journal of Speech 84 (1998): 395–415).
BOOK REVIEW
811
Not all uses of polysemy rise to the level of the fallacy of equivocation. It is very difficult to write clearly about confusion, but using Keller’s clear presentation of the issues, historians could trace out exactly how and why the polysemous language of genetics functioned to interfere with the collaborative goals of scientific argumentation. This short book is a call to arms for historians to unpack the history of this scientific language in order to avoid the tiresome mistakes of the nature/ nurture debate. I urge us all to answer her call. John P. Jackson, Jr. University of Colorado at Boulder