ABSTRACT
Historians investigating the concept of the humoral body in the early modern period mention lactating men only rarely. Historical narrations of early modern gender difference, have to draw more attention to the logic of metabolic procedures. One rare but also controversial exception, Thomas Laqueur's Making Sex, explains the curious phenomenon of the nursing father as a result of what he calls the one-sex-body in early modern humoral medicine. Among different anatomical features that account for this model of quantitative sexual difference based on heat, Laqueur placed particular emphasis on a certain "fungibility of fluids". The British physician Walter Charleton eloquently expressed the contiguousness of generation and nutrition. The physiological features of menstruation and lactation express this idea in actuality. Milk was not always produced in the breasts from uterine material, but could be derived from a liquid other than menstrual blood. The plethora model of cyclic congestion and discharge of humors played a decisive role in theories of milk production.
