Throughout the sixteenth century, learned physicians across Europe performed a diverse array of “trials” of phenomena and published reports about them. This essay traces the phrase “periculum facere” (“to make a trial”) and related terms through natural history investigations, drug testing, chymical analysis, and anatomical discoveries. Physicians used ancient precedents, their learned expertise, and pedagogical authority to anchor the epistemic status of their trials and incorporated the historical narratives of their trial-making within arguments to factual and causal knowledge, even philosophical (...) scientia. Developed from engagement with things, ancient texts, other healers, and students, this lively tradition of contrived, first-person empirical trials flourished in some academic institutions, especially the University of Padua. The frequency and visibility of sixteenth-century medical trials, especially in the education of hundreds of students annually, is essential evidence for understanding how experimentation came to be widespread in early modern Europe. (shrink)

William Harvey's famous quantitative argument fromDe motu cordis about the circulation of blood explained how a small amount of blood could recirculate and nourish the entire body, upending the Galenic conception of the blood's motion. This paper argues that the quantitative argument drew on the calculative and rhetorical skills of merchants, including Harvey's own brothers. Modern translations ofDe motu cordisobscure the language of accountancy that Harvey himself used. Like a merchant accounting for credits and debits, intake and output, goods and (...) moneys, Harvey treated venous and arterial blood as essentially commensurate, quantifiable and fungible. For Harvey, the circulation of blood was an arithmetical necessity. The development of Harvey's circulatory model followed shifts in the epistemic value of mercantile forms of knowledge, including accounting and arithmetic, also drawing on an Aristotelian language of reciprocity and balance that Harvey shared with mercantile advisers to the royal court. This paper places Harvey's calculations in a previously underappreciated context of economic crisis, whose debates focused largely on questions of circulation. (shrink)

Starting from the works by Aselli on the milky veins and Harvey on the motion of the heart and the circulation of the blood, the practice of vivisection witnessed a resurgence in the early modern period. I discuss some of the most notable cases in the century spanning from Aselli’s work to the investigations of fluid pressure in plants and animals by Stephen Hales. Key figures in my study include Johannes Walaeus, Jean Pecquet, Marcello Malpighi, Reinier de Graaf, Richard Lower, (...) Anton Nuck, and Anton de Heide. Although vivisection dates from antiquity, early modern experimenters expanded the range of practices and epistemic motivations associated with it, displaying considerable technical skills and methodological awareness about the problems associated with the animals being alive and the issue of generalizing results to humans. Many practitioners expressed great discomfort at the suffering of the animals; however, many remained convinced that their investigations were not only indispensable from an epistemic standpoint but also had potential medical applications. Early modern vivisection experiments were both extensive and sophisticated and cannot be ignored in the literature of early modern experimentation or of experimentation on living organisms across time. (shrink)