Binary Logic: Race, Expertise, and the Persistence of Uncertainty in American Sex Research

Between the mid-nineteenth and mid-twentieth centuries, American researchers tried to sort the living world by sex. Their efforts created more taxonomic problems than they solved, but as they encountered vast quantities of evidence that did not at all show an obvious or stable division between male and female bodies, they used sexual uncertainty to their professional and ideological advantage. This dissertation traces a network of scientists who built their own claims to expertise, as well as theories of racial hierarchy rooted in sexual difference, out of sexually unruly bodies. While much scholarship on the history of sex science describes the crystallization of categories and the increasing precision of definitions of sex, this dissertation focuses instead on ambiguities in the meaning of male and female, and in the meaning of sex itself. “Binary Logic” shows that the power to sort bodies by sex emerged not from solidified, agreed-upon parameters, or inherent bodily forms, but out of a mobile and malleable understanding of sex that enabled scientists to redefine their terms of classification at every turn. It also makes visible the constant categorical work required to make it appear that most humans and non-humans easily fit into binary male and female categories. This dissertation deploys the methods of Science and Technology Studies (STS), especially an attention to on-the-ground practices of fact-building and a refusal to take the pre-existence of discrete categories for granted, to integrate the history of sexuality, especially trans history, with histories of race, the life sciences, and clinical practice. It draws primarily on unpublished materials like scientists’ research notes, correspondence, and administrative records, alongside the published scientific and medical texts that emerged from them. The introduction pairs STS approaches to classification with pressing historiographical questions about who and what counts as the object of trans history, and develops a trans history methodology that accounts for the prevalence of people whose lack of conformity to standards of sex and gender was ultimately drawn back into normative categories rather than excluded from them. I demonstrate that method in action in the four chapters that follow. Each chapter examines a site in which sorting out sex became particularly fraught for the scientists attempting to do so. Chapter One investigates how nineteenth-century zoologists managed their encounters with animals that did not neatly fit into male and female categories even as they used the so-called natural world as fodder for claims about human racial hierarchies. Chapter Two looks at the disparate uses of sex as an analytic category at two eugenics laboratories in Cold Spring Harbor, New York, in the first decades of the twentieth century. At one lab, sex was a spectrum, and scientific tools could be used to gain more control over it for the purpose of improving human breeding; at the other, sex was a static binary, useful for tracking the heredity of undesirable traits to better weed them out. Chapter Three focuses in on the theoretical and clinical work of early twentieth-century gynecologist Robert Latou Dickinson, whose ideas about the commonality of intersex traits clashed with both his reluctance to classify any of his patients outside of womanhood and his ideas about the eugenic superiority of sexual dimorphism. Chapter Four explores one outcome of these debates and resulting anxieties about the meaning of sex: an early iteration of trans medicine in the 1950s and 1960s, in which the purported straightforward definition of the transsexual belied the anxiety of medical doctors convinced they might make the wrong choice in who to allow to transition. Close attention to how scientists reclassified bodies, redefined categorical criteria, and reconstituted what they considered sex itself at these four sites makes apparent the persistent flexibility of a sorting system of tremendous, frequently violent, social import—sex—that is often portrayed as immutable biological fact