305 © Springer Nature Switzerland AG 2021 F. Baldassarri, A. Blank (eds.), Vegetative Powers, International Archives of the History of Ideas Archives internationales d’histoire des idées 234, https://doi.org/10.1007/978-3-030-69709-9_18 Chapter 18 Margaret Cavendish and Vegetable Life Justin Begley Abstract This paper traces how the seventeenth-century poet, playwright, and natural philosopher, Margaret Cavendish, developed her ideas on plant life in three major publications: her 1655 Philosophical and Physical Opinions, 1664 Philosophical Letters, and 1666 Observations Upon Experimental Philosophy. As I seek to demonstrate, Cavendish’s mostly overlooked ruminations on vegetality were indispensable to her formation of a substance theory according to which all matter is endowed with life, vitality, knowledge, and, in her mature works, perceptivity. Over the course of this paper, I also suggest that her visions of matter and plant life were largely grounded in Galenic and Aristotelian insights that she extracted and adapted from a range of sources, not least from William Harvey’s feld-changing writings on the circulation of blood and the generation of animals. In building upon this material, Cavendish was driven to uphold the innate livelihood of plants against mechanical accounts and to champion a “natural” mode of classifcation that focussed on the diversity of plant attributes rather than foregrounding specifc fea- tures that humans deemed valuable or signifcant. 18.1 Introduction Recent years have witnessed a furry of interest in the seventeenth-century poet, playwright, and natural philosopher, Margaret Cavendish. Among scholars who have examined her natural philosophical output, some have now considered the bearing that her so-called “material vitalism” had on her understanding of animals. 1 Yet, while Cavendish was at least as preoccupied with investigating the nature of vegetable as animal life, her ideas on this front have been given surprisingly short shrift. My paper seeks to fll in this lacuna by surveying her views on vegetality as they were expounded in three major publications: her 1655 Philosophical and 1 See, for example, Boyle 2018, 189–214 and Broad 2002, especially 54–5. J. Begley (*) Herzog August Bibliothek, Wolfenbüttel, Germany e-mail: justin_s_begley@live.com