In 1856, twelve babies were born on Canebrake Plantation in Adams County, Mississippi: six boys and six girls. The first, Kate, arrived on January 21, born to Beck, age thirty. The last came just before the New Year—Jenny, born to Susan, age twenty-three, on December 29. One, a baby girl born to Peggy on November 12, did not survive the month. If she received a name, we do not know it. But the rest lived long enough to be entered into an inventory of lives. There, Canebrake’s proprietor, James Green Carson, noted their names, ages, and values. He priced each baby at $25 except for Kate. He rounded her age up to one and set her value at $75. Thus, the births of 1856 became $325 in human capital at the beginning of 1857. Many years before he would begin to measure their labor, Carson had already entered them into his account books as capital. 

Slaves were, quite literally, human capital, and their value could appreciate through maturation, reproduction, and health or depreciate through illness, age, and disobedience. This paper examines the different ways slaveholders sought to estimate their value. Planters used both the language and logic of “depreciation” decades before it would become a common accounting technique, and traders and auctioneers graded enslaved people into standard categories with standard prices. Though slaveholders’ calculations suggested that prices were efficient and correct, beneath their rationalizing patina was the fundamental reality that property was political—especially property in people.

Economics and the life sciences have long shared an interest in population, but in the early 1970s the status of that object changed. Whereas Malthus and his followers treated population growth as an exogenous, iron force pressing in on economics, and whereas neoclassical economists simply bracketed out the problem of human embodiment, economists now used the revamped concept of human capital to reframe population changes as fully endogenous to economic analysis. Reproduction, argued men like Gary Becker, T. Paul Schultz, and H. Gregg Lewis, was a form of capital investment based on the rational expectations of sovereign consumers: having children was like buying a fridge. 

My paper explores this microeconomic approach to human life by detailing the rise of modern theories of ‘human capital’ in the late 1950s and their application, in the 1960s, to sex and other areas previously beyond the scope of economic analysis. I show how these ideas developed alongside a new breed of economic model. Bachue-1—a mainframe simulation improbably named after the Columbian “goddess of love, fertility and harmony between nature and man”—was a joint project of the International Labor Organization and the UN Fund for Population Activities, begun in 1972. Unlike previous simulations, which modeled the world “in terms of aggregates such as ‘population,’ ‘national income accounts,’ and so forth,” Bachue was proudly “disaggregated.” Fertility and productivity interacted endogenously, via feedback loops. Through Bachue; Becker; and his colleagues, human reproduction was transformed from a natural bombshell to an individual, rational choice.

Buy the flashier car or save more for retirement? One marshmallow now or two in fifteen minutes? In the 1960s, the question of how people make decisions across time became a guiding research problem in the social sciences, following two notable trajectories. Economists like Tjalling Koopmans sought to develop a formal-mathematical model of intertemporal choice that could be derived from basic axioms of rational behavior. Simultaneously, psychologists working in the behaviorist tradition, notably Richard Herrnstein—who took over leadership of the famed Harvard Pigeon Laboratory from founder B. F. Skinner in the early 1960s—and Pigeon Lab member George Ainslie, sought to understand inter-temporal behaviors like “impatience” and “impulse control” as measurable empirical phenomena, with pigeons as models. Researchers in both fields contended that the present/future trade-offs humans—and other animals—make could be rendered by a mathematical function. For the economists, this “discounting” curve was exponential, coinciding with the practical compound-interest mathematics long used financiers, actuaries, and engineers. For the psychologists, informed by Herrnstein’s behaviorist “matching law,” this curve was hyperbolic, indicating that animals/humans tended to discount the near-future more heavily than the distant-future. Beginning in the 1980s, the economic and psychological strands began to entangle, and choice over time became a foundational problem in an emergent “behavioral economics.” As previous scholars have noted, this interdisciplinary encounter entailed a clashing and (incomplete) reconciliation of different methodologies, epistemic values, and conceptions of human nature. It also involved another, less noticed, boundary-crossing: the emergence of non-human animals as economic actors.

This panel considers the proposition that economics “has always been a science of life.” I agree, and offer three instances of the transfer and exchange of models, tools, and matters of concern between economists and biologists modeling growth (population and economic) in the 20th century. I argue that by looking at them as a group we can trace the development of attitudes towards life and growth as a problem, though each case is embedded in its own time and place. First, Raymond Pearl and Alfred Lotka’s work on life tables and the logistic curve offers a view into an early relationship between industry, government, and academic research impacting ecology, life insurance, and demography. Second, I show how Garrett Hardin’s influential paper, The Tragedy of the Commons, was taken up by two distinct groups of political economists in the Public Choice school. James Buchanan and Gordon Tulluck adapted Hardin’s model to support their analysis of rent-seeking, while Elinor Ostrom’s Workshop in Political Theory and Policy Analysis reworked the Tragedy of the Commons into a fate that could be avoided. I conclude with speculation about why these two disciplines, though far separated by traditional academic divisions, have almost compulsively looked over each others’ shoulders in multiple instances. Why do economists and biologists care enough about one another to want to borrow each others’ tools?

This paper explores efforts to apply economic logic to human life. In U.S. federal regulatory agencies, government planners and policy makers have spent over a century trying to devise a scientifically sound way to measure the economic value of lives lost or saved by public programs. The methods they have drawn on, however, have changed drastically in the past 40 years, shifting from a ‘human capital’ approach based on models of economic productivity and producing relatively low dollar values to a ‘willingness-to-pay’ approach reflecting consumer choice and producing much higher values. Why, in an era of intense deregulatory pressures, did the valuation model that produced significantly higher estimates – making it easier to justify costly regulation – ultimately win out? This unlikely transition follows a shift in the nature of professional expertise dominating the federal bureaucracy during the 1970s and 1980s, as changing conceptions of health and safety regulation during this period gave academic economists the opportunity to make new claims about the exclusive authority of microeconomic theory for understanding the economic value of life in federal planning. Supporting this argument is a comparative case, the largely unsuccessful attempt to extend the willingness-to-pay model to the valuation of life in the courtroom. Pricing human life thus results not only from the renegotiation of moral boundaries around the economic logic of the market, but also from the reorganization of expert authority and the consolidation of scientific expertise around both the meaning and the measurement of value.