The generation of animals was a difficult phenomenon to explain in the seventeenth century, having long been a problem in natural philosophy, theology, and medicine. In this paper, I explore how generation, understood as epigenesis, was directly related to an idea of rational nature. I examine epigenesis—the idea that the embryo was constructed part-by-part, over time—in the work of two seemingly dissimilar English philosophers: William Harvey, an eclectic Aristotelian, and Margaret Cavendish, a radical materialist. I chart the ways that they (...) understood and explained epigenesis, given their differences in philosophy and ontology. I argue for the importance of ideas of harmony and order in structuring their accounts of generation as a rational process. I link their experiences during the English Civil war to how they see nature as a possible source for the rationality and concord sorely missing in human affairs. (shrink)

Was Aristotle the ‘father’ and founder of the epigenesis doctrine? Historically, I will argue, this question must be answered with ‘no’. Aristotle did not initiate and had no access to a debate that described itself in terms of ‘epigenesis’ and ‘preformation’, and thus cannot be considered the ‘father’ or founder of the epigenesis-preformation controversy in a literal sense. But many ancient accounts of reproduction and embryological development contain analogies to what early modern scientist called ‘epigenesis’ and ‘preformation’, and, in this (...) analogous sense, Aristotle can be considered a precursor of the epigenesis-preformation controversy. But is Aristotle’s position actually epigenetic, as most of the traditional interpreters hold, or preformationist, as some of the recent scholars believe? I will argue against the one-sidedness of both readings that Aristotle’s account of reproduction and heredity contains mainly epigenetic, but also a few preformationist characteristics. Whereas, for instance, Aristotle’s idea of a successive development of the embryo’s parts is doubtlessly epigenetic, Aristotle’s idea that the development of the embryo is an actualization and enlargement of potential parts, which are simultaneously present in the semen, can be considered a preformationist feature. (shrink)

In a short work called De conceptione appended to the end of his Exercitationes de generatione animalium , William Harvey developed a rather strange analogy. To explain how such marvelous productions as living beings were generated from the rather inauspicious ingredients of animal reproduction, Harvey argued that conception in the womb was like conception in the brain. It was mostly rejected at the time; it now seems a ludicrous theory based upon homonymy. However, this analogy offers insight into the structure (...) and function of analogies in early modern natural philosophy. In this essay I hope to not only describe the complex nature of Harvey’s analogy, but also offer a novel interpretation of his use of analogical reasoning, substantially revising the account offered by Guido Giglioni . I discuss two points of conceptual change and negotiation in connection with Harvey’s analogy, understanding it as both a confrontation between the border of the natural and the supernatural, as well as a moment in the history of psychology. My interpretation touches upon a number of important aspects, including why the analogy was rejected, how Harvey systematically deployed analogies according to his notions of natural philosophical method, how the analogy fits into contemporary discussions of analogies in science, and finally, how the analogy must be seen in the context of changing Renaissance notions of the science of the soul, ultimately confronting the problem of how to understand final causality in Aristotelian science. In connection with the last, I conclude the essay by turning to how Harvey embeds the analogy within a natural theological cosmology. (shrink)

In early modern European natural philosophy and medicine, scholars encountered the problem of the “formless birth” in their studies into generation, alongside “monstrous” and “perfect” births. Such formless births included the hen’s egg, the unformed bear cub, and the human false conception – said to be shapeless lumps of moving flesh – and these types of conceptions influenced how natural philosophers, like William Harvey and Jan Baptiste van Lamzweerde, approached experiments on, or explanations of, generation. This article suggests that the (...) history of these unformed births provides fresh insights into how early modern scholars “thought” with formlessness. That is, early modern scholars drew on a longstanding discourse of shapeless conceptions to address the mechanisms of formless generation, “true” generation, as well as to understand other unformed or interstitial creatures in nature. The article argues that this history of thinking with formless births contributes to our picture of the significant role that unnatural births, such as “monsters”, played in early modern natural philosophy. (shrink)