The nature of light is a focus of Thomas Hobbes’s natural philosophical project. Hobbes’s explanation of the light of lucid bodies differs across his works, from dilation and contraction in Elements of Law to simple circular motions in De corpore. However, Hobbes consistently explains perceived light by positing that bodily resistance generates the phantasm of light. In Letters I.XIX–XX of Philosophical Letters, fellow materialist Margaret Cavendish attacks the Hobbesian understanding of both lux and lumen by claiming that Hobbes has illicitly (...) made abstractions from matter. In this paper, I argue that Cavendish’s criticisms rely on an incorrect understanding of the nature of Hobbesian geometry and the role it plays in Hobbes’s natural philosophy. Rather than understanding geometry as wholly abstract, Hobbes attempts to ground geometry in different ways of considering bodies and their motions. Furthermore, Hobbes’s own criticisms of abstraction suggest that he would share many of the worries she raises but deny that he falls prey to them. (shrink)

Thomas Hobbes based his natural philosophy on definitions and general principles of matter in motion, which he refrained from calling “laws of nature.” Across the channel, René Descartes had presented his own account of matter in motion in such a way that laws of nature play a central causal-explanatory role. Despite some notable differences in the two systems of natural philosophy, the content of the three Cartesian laws of nature is shared by Hobbesian principles of motion. Why is it the (...) case that Hobbes never ‘transferred’ the concept of law of nature from the sphere of civil society to the realm of nature? What is the status of the Hobbesian principles of motion if they are not laws? Answering these questions is the main aim of this article. It is shown that Hobbes made available an importantly different and genuinely original way to do natural philosophy, which renders it free of metaphysics and eschews the need to ground it in anything other than ‘natural reason’. Briefly put, Hobbes took the category of ‘laws of nature’ to involve commitments that cannot be met in the natural world, unless natural philosophy loses its autonomy from theology and metaphysics. (shrink)

Hobbes is known for bridging natural and political philosophy, but less attention has been given to how this distinguishes the Hobbesian conception of the self from individualist strands of liberalism. First, Hobbes’s determinism suggests a conception of the self in which externalities determine the will and what the self is at every moment. Second, there is no stable conception of the self because externalities keep it in a constant state of flux. The metaphysical underpinnings of his project downplay the notion (...) of a purely individualistic conception of the self, pointing to a positivist theory of criminology relying upon external forces. This theory is especially prescient with respect to twentieth-century variants of positivism that focus upon how social organization affects personality. In a sense, then, modern criminological theory is indebted to Hobbes’s focus upon the connections between externalities and the self; a focus that illuminates new ways of viewing responsibility and accountability. (shrink)

ABSTRACT The concepts of liberty and representation reveal tensions in Hobbes's political anthropology that only a study of the development of his philosophical materialism can fully elucidate. The first section of this article analyses the contradictory definitions of liberty offered in De cive, and explains them against the background of Hobbes's elaboration of a deterministic concept of conatus during the 1640s. Variations in the concepts of conatus and void between De motu and De corpore will shed light on ideas of (...) individuality, unity and agency that carry direct political relevance. The second section explains why the concept of representation that Hobbes elaborated at the end of the decade in Leviathan cannot be interpreted within an exclusively political and juridical framework. Rather, I will claim that it should be explained in the light of Hobbes's materialist theory of the power exerted by the sovereign persona on human imagination. (shrink)

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. (shrink)