Nature as Norm in Medieval Medical Discussions of Maternal Breastfeeding and Wet-Nursing

Medieval discussions about breastfeeding were saturated with moral and social meanings and arguments about how a good mother should behave and what makes for a happy, healthy baby. At the center was the question of who should breastfeed, the mother or a wet nurse. While the church sanctioned maternal breastfeeding as a moral norm, recourse to wet nurses was the norm for elites, and the custom spread in the later Middle Ages to the middling segments of society. Medieval physicians formulated their advice according to their understanding of the moral and normative authority of nature, but also in complex dialogue with contemporary pastoral theory and moral philosophy (which rejected wet-nursing), as well as contemporary social practices, values, and beliefs. Physicians recognized maternal breastfeeding as the best and most natural option because of the physiological continuity between gestation and lactation, yet their advice was adapted to the social realities of their patrons and patients by giving guidance about choosing a good wet nurse and controling her manner of life. Contrary to what is often claimed or supposed, the notion that the milk of amoral and bad-mannered wet nurses might lead to the degeneration of children did not originate from Galenic physiology but from nonmedical sources. Physicians themselves were reticent about attributing quasi-hereditary powers to mother’s milk, insisting instead on the dangers of neglect in the care of infants.