Émilie Du Châtelet and the Foundations of Physical Science

Katherine Brading

• Publisher: Routledge
• Year: 2019
• Print ISBN: 9781032094137
• eBook ISBN: 9780429787195
• Topic: Philosophy
• Subtopic: Modern Philosophy

The centerpiece of Émilie Du Châtelet's philosophy of science is her Foundations of Physics, first published in 1740. The Foundations contains epistemology, metaphysics, methodology, mechanics, and physics, including such pressing issues of the time as whether there are atoms, the appropriate roles of God and of hypotheses in scientific theorizing, how (if at all) bodies are capable of acting on one another, and whether gravity is an action-at-a-distance force. Du Châtelet sought to resolve these issues within a single philosophical framework that builds on her critique and appraisal of all the leading alternatives (Cartesian, Newtonian, Leibnizian, and so forth) of the period. The text is remarkable for being the first to attempt such a synthetic project, and even more so for the accessibility and clarity of the writing. This book argues that Du Châtelet put her finger on the central problems that lay at the intersection of physics and metaphysics at the time, and tackled them drawing on the most up-to-date resources available. It will be a useful source for students and scholars interested in the history and philosophy of science, and in the impact of women philosophers in the early modern period.

1 Introduction

The centerpiece of Émilie Du Châtelet’s philosophy is her Institutions de Physique (hereafter her Foundations of Physics or simply her Foundations), first published in 1740. My purpose here is to offer an introduction to the philosophy found within.¹ The Foundations contains epistemology, metaphysics, methodology, mechanics, and physics, including such pressing issues of the time as whether matter is infinitely divisible, the appropriate roles of God and of hypotheses in scientific theorizing, and whether gravity is an action-at-a-distance force. Du Châtelet sought to resolve these issues within a single philosophical framework, building on her critique and appraisal of all the leading alternatives of the period (Cartesian, Newtonian, Leibnizian, and so forth). The text is remarkable for being the first to attempt such a synthetic project. Du Châtelet put her finger on the central problems that lay at the intersection of physics and metaphysics at the time, and tackled them using the most up-to-date resources available.

With such a wide range of philosophical topics being covered in a relatively short text, it would be easy to pick on particular topics and criticize Du Châtelet’s treatment of them individually. Such criticisms are surely important for the long-term evaluation of the text, but first things first. The Foundations has yet to receive detailed treatment as a work of philosophy, and we have yet to establish the overall philosophical goals of the book. Our first reading of the arguments should be with respect to these goals. And so, our first question must be: what was Du Châtelet trying to achieve?

Du Châtelet tells us in her Preface that there was, at the time she was writing, no complete and up-to-date textbook in physics available in French, and that her aim is to rectify this by making material from Newton and Leibniz available in French. By itself, this would give a descriptive goal to the project, reporting the work of others, but Du Châtelet makes choices about what materials to include (and exclude), and she puts these materials to work in a philosophical project of her own. According to the reading of the Foundations that I offer in this book, the central physical and metaphysical problem of the text concerns how it is that bodies act upon one another, and the central epistemological problem concerns the appropriate method by which to address this problem of bodily action. These are the goals with respect to which we should read and assess the text.

In what follows, I outline my view of Du Châtelet’s goals in the Foundations of Physics and my preferred reading of the text, to be developed in more detail in Chapters 2–4. In Section 1.1, I provide some background to the Foundations and some guidance on how to read it. This section draws on the existing secondary literature, which I discuss in more detail in Section 1.2. In Section 1.3, I provide an extended overview of the remainder of this book, which can be summarized as follows.

In Chapter 2, I show that the problem of method plays a crucial role in the early chapters of the Foundations, and I describe Du Châtelet’s innovative two-pronged methodology for scientific theorizing. Her introduction of this methodology was motivated by her interest in bodily action, including Newtonian action-at-a-distance, vis viva, and human agency. In Chapter 3, I discuss Du Châtelet’s detailed account of matter, bodies, and force, and in Chapter 4, I present her attempts to address several controversial issues of bodily action using the resources set out in Chapters 2 and 3. Our understanding of her approach to these issues depends upon our understanding of her method and of her account of matter, body, and force; and reciprocally our understanding of these resources, as she develops them in her text, is deepened by our understanding of the problems they are intended to help solve. By framing our philosophical engagement with Du Châtelet’s Foundations of Physics in the way that I propose, we are able to do justice to the philosophical richness of the text and to its significance for history of philosophy.

1.1 Reading the Foundations: Some Background and Context

The text that I discuss in this book is the first edition of the Foundations of Physics, published in 1740.² A second edition appeared in 1742, which was translated into both German and Italian (in 1743).³ Crucial passages were reproduced (often without attribution) in the Encyclopédie (hereafter Encyclopedia) of Diderot and d’Alembert (publication of which began in 1751).⁴ A partial manuscript version of the text is extant, providing evidence of substantial changes shortly before publication (about which more later). For a deeper understanding of the philosophy of the Foundations, much work remains to be done to study the philosophical significance of changes between the manuscript, the 1740 edition, and the 1742 second edition, as well as comparisons with the German and Italian translations and among variants of the editions. In this book, I am writing only about the 1740 published edition (with occasional references to the manuscript).

The existing English-language secondary literature on the Foundations is small (for more details, see Section 1.2 and references throughout). Three areas require more detailed research. First, work is needed on the differences between the multiple versions of the text, as noted. Second, there is a great deal more work to be done in studying the philosophical context, sources, and influence of the Foundations. Third, the study of Du Châtelet’s corpus as a whole, investigating the philosophical relationships among the texts, is a project as yet barely begun. My discussion of the Foundations of Physics is inevitably impoverished due to the early stage of development of these three areas of research. My hope is that the account of the Foundations offered here, despite its limitations, will prove useful for further advancing the scholarship on Du Châtelet’s philosophy.

In this section, I offer some background and context that help us understand how to read the Foundations. In the history of philosophy, Du Châtelet’s Foundations of Physics is situated after Locke’s Essay (1689); Newton’s Principia (in the three editions of 1687, 1713, 1726; see Newton, 1999); The Leibniz-Clarke Correspondence (published in 1717; see Leibniz and Clarke, 1998); and Berkeley’s Principles (1710), Dialogues (1713), and De Motu (1721). It is contemporaneous with Hume’s Treatise (1739–40), and it comes before Hume’s An Enquiry Concerning Human Understanding (first published under a slightly different title in 1748) as well as before Kant’s earliest publication, in 1749, on living forces (Kant, 2012b), in which he references Du Châtelet. Philosophically, Du Châtelet’s primary concern is with bodily causation: with how it is that bodies are capable of acting causally upon one another, and with how we can know that they do. As we will see, this concern takes her into a broad range of issues familiar from the philosophy of the period.

It is widely acknowledged that Du Châtelet assisted Voltaire in the writing of his Éléments de la philosophie de Newton, first published in 1738.⁵ Du Châtelet published a review of this book (1738), and in the Preface to the Foundations she makes explicit her intention of going beyond the “narrow boundaries” of Voltaire’s exposition (2009, 1.VI). Du Châtelet’s work with him (including their experimental work at Cirey, her readings in philosophy and physics, her lessons in mathematics, her discussions with such figures as Algarotti, and her conversations and correspondence with Maupertuis) provides the intellectual context for her writing of the Foundations.⁶ Her studies in philosophy included Plato’s Dialogues, Locke’s Essay, and The Leibniz-Clarke Correspondence, among other things.⁷ Du Châtelet’s engagement with Locke is rarely explicit in the Foundations, unlike her engagement with Descartes, Leibniz, Newton, and Wolff, but it is nevertheless a crucial presence.⁸

The first version of the Foundations was approved for publication on 18 September 1738. The “approbation” makes clear that the original work contained an exposition of “the principles of philosophy” of Leibniz and of Newton. It states (my translation)⁹:

Approbation

I have read, by order of the Lord Chancellor, a Manuscript which has for its title: Foundations of Physics, this Work in which are explained the principles of the Philosophy of Mr. Leibniz and those of Mr. Newton, is written with great clarity, and I have found in it nothing that could prevent printing. Paris, 18 September 1738. Signed Pitot.

Du Châtelet’s review of Voltaire’s Elements had appeared in that same month, to be followed soon after by her Dissertation on the Nature and Propagation of Fire (1739). Other work completed or in progress at the time includes her essays on optics and on liberty, and while not published during her lifetime both circulated in manuscript form.

An abrupt suspension of printing of the Foundations took place in the winter of 1738–39, and there has been much speculation as to the causes, not least since we do not have a complete version of the original manuscript.¹⁰ Relevant factors include her ongoing discussions with Maupertuis concerning vis viva and her desire to learn more mathematics before proceeding.¹¹ Samuel König arrived in Cirey as a mathematics tutor in the spring of 1739,¹² and once Du Châtelet discovered that he had studied under Wolff, she enlisted his help “to summarize key parts of the chapters that she needed for her revisions” (Zinsser, 2006, p. 171). Whatever the motivation and original plans for revising the text, the upshot involved major changes to the opening chapters, drawing on the metaphysics of Leibniz and of Wolff.

Famously, König accused Du Châtelet of having copied from him in preparing the revised chapters of the Foundations. In my opinion, the evidence (from Du Châtelet’s own prior reading, from her correspondence (especially in the late 1730s with Maupertuis), from the development of her philosophical positions through the period in question, and from König’s own behavior and relationships) refutes any charge of plagiarism. I will not pursue this here.¹³ Insofar as my work makes a contribution to this issue, it does so by demonstrating the philosophical agenda that runs through the entire text of the Foundations; by showing that this agenda predated the revisions; and by thereby making vivid the philosophical contributions of the author through the choices of the materials, the formulation that she gives, the changes that she makes, and the uses to which she puts the materials in the arguments that she makes in the text.

The Foundations was resubmitted for publication in September 1740 and appeared in print in December of that year. The immediate reception of the text is discussed by Janik (1982, pp. 97–8) and by Zinsser (2006, p. 191). Du Châtelet had intended anonymous publication, in order to get an impartial response to the book, but this intention was thwarted by König who revealed her authorship shortly before publication. Nevertheless, Du Châtelet sent copies of the book to leading figures, and it was positively reviewed in the Journal des sçavans (in two parts, the first in December 1740 and the second in March 1741), with extensive quotations. The ongoing influence of the text, both direct and indirect (e.g. through extracts reproduced in the Encyclopedia of Diderot and d’Alembert; see earlier), requires further research. Suisky (2012, p. 153) offers the following assessment: “The extraordinary role Du Châtelet’s Institutions de physique played in the eighteenth century is… confirmed by… the esteem her treatise met in the public that was probably surpassed only by Euler’s Lettres à une princesse d’Allemagne”.

In late April 1740, Du Châtelet wrote in a letter to Frederick of Prussia that the idea of writing such a book began with lessons that she prepared for her young son, Florent-Louis, who was ten years old at the time (see Zinsser, 2006, p. 165). Of this, Wade (1969, p. 277) writes, “Although Mme du Châtelet adopted early the fiction of an essay on physics written for her son, in reality what she was doing was producing a text on physics”. Who, then, was her audience, and how should we situate her text within the literature of the time?¹⁴

I think it is clear that Du Châtelet did not see herself as writing in the genre of Fontanelle and Algarotti, who wrote “for the ladies” and whose work she viewed as lightweight. I agree with Harth’s assessment (1992, p. 202; see also Hutton, 2012, p. 85):

It is more likely that she thought of herself as a successor to Rohault in the Cartesian enterprise of writing serious but comprehensible philosophy. Her stated goal was not to convert her public to the party of philosophy, as Fontanelle wished to do, but rather to add to the stock of knowledge in a collective search for truth.

That being said, I also agree with Kawashima (2004) that Du Châtelet did not model her text on either Rohault’s textbook or Descartes’s Principles of Philosophy (though see Detlefsen, 2014 and forthcoming). Rather, the structure and list of topics is that found in the Newtonian texts explicitly recommended by Voltaire in his Elements: books by Keill, Musschenbroek, ’s Gravesande, and Pemberton (see Appendix 1 for details). I take these to have been her model.¹⁵ As we shall see in Chapter 2, all of these texts begin with considerations of method. The topics covered thereafter match those of the Foundations (see Appendix 1).¹⁶ I believe that...

Table of contents

• Cover
• Half Title
• Series Page
• Title Page
• Copyright Page
• Dedication Page
• Table of Contents
• Preface
• 1 Introduction
• 2 Method
• 3 Matter, Body, Force
• 4 Bodies in Action
• Appendix 1: Chapter Headings from Du Châtelet’s Foundations of Physics and from Several Early 18th-Century Newtonian Textbooks
• References
• Index