ABSTRACT: In this essay, I study the contested role of magnification as an observational strategy in the generation theories of William Harvey and René Descartes. During the seventeenth century, the grounds under the discipline of anatomy were shifting as knowledge was increasingly based on autopsia and observation. Likewise, new theories of generation were established through observations of living beings in their smallest state. But the question formed: was it possible to extend vision all the way down to the first points of life? Arguing that the potential of magnification hinged on the metaphysics of living matter, I show that Harvey did not consider observational focus on the material composition of blood and embryos to be conducive to knowledge of living bodies. To Harvey, generation was caused by immaterial, and thus in principle invisible, forces that could not be magnified. Descartes, on the other hand, believed that access to the subvisible scale of natural bodies was crucial to knowledge about their nature. This access could be granted through rational introspection, but possibly also through powerful microscopes. The essay thus ends with a reflection on the importance of Cartesian corpuscularianism for the emergence of microscopical anatomy in seventeenth-century England.
Magnifying the first points of life: Harvey and Descartes on generation and scale, History of Science (August 13, 2021)
Girolamo Fabrici d’Acquapendente, De formatione ovi et pulli (Padua: Aloysii Bencii, 1621), plate 1. Courtesy of Bibliothèque interuniversitaire de santé (Paris).
ABSTRACT: The middle of the seventeenth century saw the emergence of a new kind of botanical observation: Microscopical observations of seeds. Previously, naturalists had made observations of seeds to complete their description of plants published in herbals, but for the first generation of Royal Society microscopists—Henry Power, Robert Hooke, and Nehemiah Grew—seeds became the centre of attention. This essay details this transition in plant knowledge by zooming in on just one kind of seeds: The poppy seed. Poppy seeds were abundant in early modern England as they were found in fields, gardens, kitchens and pharmacies. They were also excellent specimens to look at through microscopes, but for different reasons. Focusing on pictorial representation, especially, I analyse the diverse ambitions behind Power, Hooke, and Grew’s observations of poppy seeds, and how they used pictures to further these. The comparison of these three observations of the same specimen highlights the diversity of strategies for scientific representation in the early Royal Society while showing that intense, instrument-enhanced observation did not produce a stable epistemic object, but a multiplicity of epistemic images.
Picturing Seeds of Poppies: Microscopes, Specimens, and Representation in Seventeenth-Century English Botany, Nuncius 37, no. 2 (February 2, 2022): 346-373
Robert Hooke, Micrographia (London: John Martyn and James Allestry, 1665), Schema XIX
ABSTRACT: Metaphors played an indispensable role in the development and legitimization of early modern economic rationalities. One of the most prevalent metaphors described the state as a body, a strong expression of which is found in Thomas Hobbes’ Leviathan (1651). But both the concept of the state and the body were constantly being reconfigured in this period. In this chapter, I argue that Hobbes’ conception of economy as a closed system of circulation ensuring the health and life of the state gained its specific character as a product of Hobbes’ dependency on William Harvey’s anatomical theory of the circulation of blood for his description of the state as a body. For Harvey, a proper circulation of blood was what ensured the life of the animal body, and thus for Hobbes the economy understood as circulation of money was nothing but a means to ensure the life of the political body.
Circulation of Blood and Money in Leviathan: Hobbes on the Economy of the Body, in Bek-Thomsen, J. et. al. (eds.), History of Economic Rationalities (Dordrecht: Springer, 2017), pp. 31-41
Thomas Hobbes, Leviathan, Or the Matter, Forme and Power of a Commonwealth Ecclesiasticall and Civil (London/ Andrew Crooke, 1651), frontispiece engraving by Abraham Bosse
ABSTRACT: Making observations of nature’s invisible parts has always been one of the strongest natural-philosophical ambitions. In Antiquity, materialist philosophers like Epicurus imagined how nature is made up of fundamental parts called atoms. In the early modern period, this ambition was fueled by the invention of an instrument, which – thought some natural philosophers – would finally reveal nature’s fundamental parts: The microscope. Of course, such parts were never found. But through their lenses, early modern naturalists instead found a variety of often surprising things never seen before: minuscule insects, plant fibers, pollen dust, animalcules, and blood cells. A whole new middling world emerged between the worlds of the invisible and the visible. Here, I will provide an overview of some of the first observations made with microscopes, the competing attitudes towards magnification, and the ways in which microscopic vision changed ideas about subvisible nature.
Microscopy in Early Modern Natural Philosophy, in Jalobeanu, D.; Wolfe, Charles T. (eds.), Encyclopedia of Early Modern Philosophy and the Sciences (Dordrecht: Springer, 2020)
Robert Hooke, Micrographia (London: John Martyn and James Allestry, 1665), Schema I