In the Monadology Leibniz has us imagine a thinking machine the size of a mill in order to show that matter can’t think. The argument is often thought to rely on the unity of consciousness and the notion of simplicity. Leibniz himself did not see matters this way. For him the argument relies on the view that the qualities of a substance must be intimately connected to its nature by being modifications, limitations of its nature. Leibniz thinks perception is not (...) a modification of matter because it is active and matter is passive. At the same time, there are traces in Leibniz of a different argument that relies on the notion of internal action, which may involve the notion of simplicity. Critics have sometimes charged that the Mill Argument is an argument from ignorance, but Leibniz was aware of this problem and made clear that he did not make that mistake. (shrink)

This is a very informative and lucid account of the career of a central philosophical topic in eighteenth‐century Britain, the debate between libertarians and necessitarians, from Locke to Dugald Stewart. The work has many strengths, and I learnt much from it. It will be of great interest to historians of the period, but the readership should be wider than that. Those working on the debate today should also read this book. Harris (quite legitimately) does not see his task as that (...) of a historian of philosophy, mining old texts in pursuit of contemporary discussion. Instead he seeks to understand the philosophers and their problems on their own terms. In doing so, however, he offers an alternative perspective that may be enlightening to those in the thick of present‐day trench warfare. He not only discusses some neglected figures but also changes our understanding of those with whom we are familiar, especially Hume. I begin by laying out the main themes of the book and its contents. I then discuss Harris' treatment of Hume in more detail. (shrink)

Leibniz's mill argument in 'Monadology' 17 is a well-known but puzzling argument against materialism about the mind. I approach the mill argument by considering other places where Leibniz gave similar arguments, using the same example of the machinery of a mill and reaching the same anti-materialist conclusion. In a 1702 letter to Bayle, Leibniz gave a mill argument that moves from his definition of perception (as the expression of a multitude by a simple) to the anti-materialist conclusion. Soon afterwards, in (...) the Preface to the New Essays, Leibniz gave a different mill argument. That argument depends upon there being no arbitrary and inexplicable connections in nature, because God would not create such things. Later, in the 'Monadology', Leibniz again used the mill example in arguing against materialism. That passage too, I argue, uses an argument from inexplicability rather than from Leibniz's definition of perception. (shrink)

The prominent place 0f corpuscularizm mechanism in L0ckc`s Essay is nowadays universally acknowledged} Certainly, L0ckc’s discussions 0f the primary/secondary quality distinction and 0f real essences cannot be understood without reference to the corpuscularizm science 0f his day, which held that all macroscopic bodily phenomena should bc explained in terms 0f the motions and impacts 0f submicroscopic particles, 0r corpuscles, each of which can bc fully characterized in terms of 21 strictly limited range 0f (primary) properties: size, shape, motion (or mobility), (...) and, perhaps, solidity 0r impcnctrability.2 Indeed, L0ckc’s lists 0f primary quali-. (shrink)

The prominent place of corpuscularian mechanism in Locke's Essay is nowadays universally acknowledged. Certainly, Locke's discussions of the primary/secondary quality distinction and of real essences cannot be understood without reference to the corpuscularian science of his day, which held that all macroscopic bodily phenomena should be explained in terms of the motions and impacts of submicroscopic particles, or corpuscles, each of which can be fully characterized in terms of a strictly limited range of properties: size, shape, motion, and, perhaps, solidity (...) or impenetrability. Indeed, Locke's lists of primary qualities are quite consistent with those found in the work of his friend Robert Boyle, a prominent defender of the corpuscularian program; his real essences of substances appear to be corpuscular constitutions, arrangements of particles. (shrink)

I explore Locke’s complex attitude toward the natural philosophy of his day by focusing on Locke’s own treatment of Newton’s theory of gravity and the presence of Lockean themes in defenses of Newtonian attraction/gravity by Maupertuis and other early Newtonians. In doing so, I highlight the inadequacy of an unqualified labeling of Locke as “mechanist” or “Newtonian.”.

Section 17 of Leibniz’s Monadology contains a famous argument in which considerations of what it would be like to enter a machine that was as large as a mill are offered as reasons to reject materialism about the mental. In this paper, I provide a critical discussion of Leibniz’s mill argument, but, unlike most treatments, my discussion will focus on texts other than the Monadology in which considerations of the mill also appear. I provide a survey of three previous interpretations (...) of the argument and a partial defence of one of them, namely the one that Marc Bobro and I offered in Stepping Back Insider Leibniz's Mill (The Monist, 1998). However, I also argue that a fourth interpretation is necessary to account for the appearances of Leibniz’s mill in at least some of his writings. (shrink)

In the early years of the eighteenth century Leibniz had several interactions with John Toland. These included, from 1702 to 1704, discussions of materialism. Those discussions culminated with the consideration of Toland's 1704 Letters to Serena, where Toland argued that matter is necessarily active. In this paper I argue for two main theses about this exchange and its consequences for our wider understanding. The first is that, despite many claims that Toland was at the time of Letters to Serena a (...) Spinozist, we can make better sense of him as a sort of Hobbesian materialist. The second main point concerns reasons for materialism, and in particular a story Locke tells in the Essay about materialists' motives. Toland defends his materialism by arguing that matter is active, and argues that matter is active by using a conceivability argument. But this is not the crude conceivability argument that Locke suggests motivates materialists. This (together with reflecting on some of Hobbes's arguments) suggests that we might well tell a Lockean story about reasons for early modern materialism, but not Locke's story. (shrink)