: This paper investigates the influence of Galileo's natural philosophy on the philosophical and methodological doctrines of Thomas Hobbes. In particular, I argue that what Hobbes took away from his encounter with Galileo was the fundamental idea that the world is a mechanical system in which everything can be understood in terms of mathematically-specifiable laws of motion. After tracing the history of Hobbes's encounters with Galilean science (through the "Welbeck group" connected with William Cavendish, earl of Newcastle and the "Mersenne (...) circle" in Paris), I argue that Hobbes's 1655 treatise De Corpore is deeply indebted to Galileo. More specifically, I show that Hobbes's mechanistic theory of mind owes a significant debt to Galileo while his treatment of the geometry of parabolic figures in chapter 16 of De Corpore was taken almost straight out of the account of accelerated motion Two New Sciences. (shrink)

_ Source: _Volume 29, Issue 1, pp 9 - 38 Hobbes tried to develop a strict version of the mechanical philosophy, in which all physical phenomena were explained only in terms of bodies in motion, and the only forces allowed were forces of collision or impact. This ambition puts Hobbes into a select group of original thinkers, alongside Galileo, Isaac Beeckman, and Descartes. No other early modern thinkers developed a strict version of the mechanical philosophy. Natural philosophies relying solely on (...) bodies in motion require a concept of inertial motion. Beeckman and Descartes assumed rectilinear motions were rectilinear, but Galileo adopted a theory which has been referred to as circular inertia. Hobbes’s natural philosophy depended to a large extent on what he called “simple circular motions.” In this paper, I argue that Hobbes’s simple circular motions derived from Galileo’s belief in circular inertia. The paper opens with a section outlining Galileo’s concept, the following section shows how Hobbes’s physics depended upon circular motions, which are held to continue indefinitely. A third section shows the difficulty Hobbes had in maintaining a strictly mechanistic philosophy, and the conclusion offers some speculations as to why Galileo’s circular inertia was never entertained as a serious rival to rectilinear inertia, except by Hobbes. (shrink)

Hobbes on Demonstration and Construction DAVID GAUTHIER 1~ IN 1656 Hobbes published Six Lessons to the Professors of Mathematics, with an Epistle Dedicatory to the Marquis of Dorchester, Lord Pierrepont. In this Epistle, Hobbes distinguishes the demonstrable from the indemonstrable arts: "demonstrable are those the construction of the subject whereof is in the power of the artist himself, who, in his demonstration, does no more but deduce the consequences of his own operation" . Although this passage, with the explication Hobbes (...) offers for it and the consequences he draws from it, and a similar discussion in De homine, published two years later, have not been unnoticed, their significance for Hobbes's account of science in general, and civil philosophy or politics in particular, has not, I think, been I am grateful to the University of East Anglia for appointing me a Visiting Research Fellow during the period in which the first draft of this paper was written. A second draft was presented at the Third Quadrennial International Fellows Conference of the Center for Philosophy of Science at the University of Pittsburgh, sponsored by the Florence Center for the History and Philosophy of Science. I am grateful for the remarks of my commentator, J. E. McGuire, and for the discussion. I am also grateful for the comments of the two referees who read this paper for the Journal of the History of Philosophy. References to Hobbes's works appear as.. (shrink)

Hobbes and Wallis's "battle of the books" illuminates the intimate relationship between science and crucial seventeenth-century debates over the limits of sovereign power and the existence of God.