Motion as an Accident of Matter: Margaret Cavendish and Thomas Hobbes on Motion and Rest

Abstract

Margaret Cavendish is widely known as a materialist. However, since Cavendishian matter is always in motion, "matter" and "motion" are equally important foundational concepts for her natural philosophy. In Philosophical Letters (1664), she takes to task her materialist rival Thomas Hobbes by assaulting his account of accidents in general and his concept of "rest" in particular. In this article, I argue that Cavendish defends her continuous-motion view in two ways: first, she claims that her account avoids seeing accidents as capable of generation and annihilation, which she argues is inconceivable; and second, she contends that according to Hobbes's own view "rest" is an absurd conception since it cannot be drawn from experience. Beyond its function as a defense, I claim that Cavendish's focused criticism of "rest" shows that she is a perceptive reader of Hobbes's natural philosophy, insofar as her criticisms undercut the two a priori principles of Hobbesian physics. Finally, I show how her views developed in more detail in Philosophical and Physical Opinions (1663) and Observations upon Experimental Philosophy ([1666] 2001) avoid the worries she raises for Hobbesian materialism.

Veil of Light: The Role of Light in Cavendish’s Visual Perception

“…She writes in the PL, "for Perception is but the effect of the Sensitive and rational Motions, and not the Motions of the Perception; neither doth the pressure of parts upon parts make Perception" (1664: 18). Her criticisms are well documented in the works of Adams (2016) and Boyle (2019) so I will not elaborate on her arguments here. Broadly, Cavendish views what Boyle (2019: 238) terms the "pressure model of perception" (PMP) which Hobbes furthers as unable to explain the variety of sense perception.…”

“…11 7. Adams (2016) and Lascano (2021) discuss whether the external object causes patterning; Michaelian (2009: 39) defines patterning as an imitation or copy of external objects.…”

Natural Philosophy, Abstraction, and Mathematics among Materialists: Thomas Hobbes and Margaret Cavendish on Light

“…Cavendish appeals to the self-motions of matter to explain human visual perception. Against the Hobbesian view that visual perception is caused by pressure from illuminated external objects continued through media until reaching the sense organs, 11 Cavendish posits that sensitive matter and rational matter coordinate with one another in perception. In Letters she describes this as a "double perception" (Letter I.IV) [3] (pp.…”

“…Adams [11] (pp. 503-507) offers a similar reading of Cavendish's criticisms of Hobbes in Letter I.XVII [3] (pp.…”

“…See also Prins [8] regarding accusations by Seth Ward that Hobbes plagiarized others' work in optics. For discussion of Cavendish's criticisms of the Hobbesian notion of 'rest' and her view that matter is always in motion, see Adams [11]. 5 See Jesseph [12] for discussion of these principles.…”