The notions of conservation and relativity lie at the heart of classical mechanics, and were critical to its early development. However, in Newton’s theory of mechanics, these symmetry principles were eclipsed by domain-specific laws. In view of the importance of symmetry principles in elucidating the structure of physical theories, it is natural to ask to what extent conservation and relativity determine the structure of mechanics. In this paper, we address this question by deriving classical mechanics—both nonrelativistic and relativistic—using relativity and (...) conservation as the primary guiding principles. The derivation proceeds in three distinct steps. First, conservation and relativity are used to derive the asymptotically conserved quantities of motion. Second, in order that energy and momentum be continuously conserved, the mechanical system is embedded in a larger energetic framework containing a massless component that is capable of bearing energy (as well as momentum in the relativistic case). Imposition of conservation and relativity then results, in the nonrelativistic case, in the conservation of mass and in the frame-invariance of massless energy; and, in the relativistic case, in the rules for transforming massless energy and momentum between frames. Third, a force framework for handling continuously interacting particles is established, wherein Newton’s second law is derived on the basis of relativity and a staccato model of motion-change. Finally, in light of the derivation, we elucidate the structure of mechanics by classifying the principles and assumptions that have been employed according to their explanatory role, distinguishing between symmetry principles and other types of principles (such as compositional principles) that are needed to build up the theoretical edifice. (shrink)

Misconceptions about energy conservation abound due to the gap between physics and secondary school chemistry. This paper surveys this difference and its relevance to the 1690s–2010s Leibnizian argument that mind-body interaction is impossible due to conservation laws. Justifications for energy conservation are partly empirical, such as Joule’s paddle wheel experiment, and partly theoretical, such as Lagrange’s statement in 1811 that energy is conserved if the potential energy does not depend on time. In 1918 Noether generalized results like Lagrange’s and proved (...) a converse: symmetries imply conservation laws and vice versa. Conservation holds if and only if nature is uniform. The rise of field physics during the 1860s–1920s implied that energy is located in particular places and conservation is primordially local: energy cannot disappear in Cambridge and reappear in Lincoln instantaneously or later; neither can it simply disappear in Cambridge or simply appear in Lincoln. A global conservation law can be inferred in some circumstances. Einstein’s General Relativity, which stimulated Noether’s work, is another source of difficulty for conservation laws. As is too rarely realized, the theory admits conserved quantities due to symmetries of the Lagrangian, like other theories. Indeed General Relativity has more symmetries and hence more conserved energies. An argument akin to Leibniz’s finally gets some force. While the mathematics is too advanced for secondary school, the ideas that conservation is tied to uniformities of nature and that energy is in particular places, are accessible. Improved science teaching would serve the truth and enhance the social credibility of science. (shrink)

This paper examines Du Châtelet’s and Kant’s responses to the famous vis viva controversy – Du Châtelet in her Institutions Physiques (1742) and Kant in his debut, the Thoughts on the True Estimation of Living Forces (1746–49). The Institutions was not only a highly influential contribution to the vis viva controversy, but also a pioneering attempt to integrate Leibnizian metaphysics and Newtonian physics. The young Kant’s evident knowledge of this work has led some to speculate about his indebtedness to her (...) philosophy. My study corrects such speculations as well as misunderstandings of the Living Forces. This corrective result has implications for how to investigate Kant’s relation to the ever-evolving landscape of Leibniz exegeses. (shrink)

ArgumentAccording to a long-standing interpretation which traces back to Max Jammer'sConcepts of Force(1957), Ruggiero G. Boscovich would have developed a concept of force in the tradition of Leibniz's dynamics. In his variation on the theme, basic properties of matter such as solidity or impenetrability would be derived from an interplay of some “active” force of attraction and repulsion that any primary element of nature (“point of matter” in Boscovich's theory) would possess. In the present paper I discuss many flaws of (...) this interpretation and argue for an alternative point of view, according to which the crucial aspect in the development of Boscovich's natural philosophy is his early definition of forces as “mathematical determinations” to have a certain state of motion. This is consistent with a Newtonian background and has as its epistemological consequence a certain agnosticism about the nature of forces and a “mathematical neutralism” (mathematics as a neutral tool, allowing for a plurality of interpretations). (shrink)

This inaugural handbook documents the distinctive research field that utilizes history and philosophy in investigation of theoretical, curricular and pedagogical issues in the teaching of science and mathematics. It is contributed to by 130 researchers from 30 countries; it provides a logically structured, fully referenced guide to the ways in which science and mathematics education is, informed by the history and philosophy of these disciplines, as well as by the philosophy of education more generally. The first handbook to cover the (...) field, it lays down a much-needed marker of progress to date and provides a platform for informed and coherent future analysis and research of the subject. -/- The publication comes at a time of heightened worldwide concern over the standard of science and mathematics education, attended by fierce debate over how best to reform curricula and enliven student engagement in the subjects There is a growing recognition among educators and policy makers that the learning of science must dovetail with learning about science; this handbook is uniquely positioned as a locus for the discussion. -/- The handbook features sections on pedagogical, theoretical, national, and biographical research, setting the literature of each tradition in its historical context. Each chapter engages in an assessment of the strengths and weakness of the research addressed, and suggests potentially fruitful avenues of future research. A key element of the handbook’s broader analytical framework is its identification and examination of unnoticed philosophical assumptions in science and mathematics research. It reminds readers at a crucial juncture that there has been a long and rich tradition of historical and philosophical engagements with science and mathematics teaching, and that lessons can be learnt from these engagements for the resolution of current theoretical, curricular and pedagogical questions that face teachers and administrators. (shrink)

This thesis presents an interpretation of Immanuel Kant’s theoretical philosophy in which the notion of ‘force’ is of central importance. My analysis encompasses the full span of Kant’s theoretical and natural-scientific writings, from the first publication to the drafts of an unfinished final work. With a close focus on Kant’s texts, I explicate their explicit references to force, providing a narrative of the philosophical role and significance of force in the various periods of the Kantian oeuvre. This represents an intervention (...) into Kant scholarship that seeks to correct the marginal role accorded to ‘force’. The central problem that emerges through the thesis’ attention to force is: how to interpret the simultaneous separation and connection of physical and psychological forces in Kant’s mature, critical philosophy? Physical and psychological forces are strictly separated, and yet a common, ontological conception of force underpins these two domains. I show that this issue has its basis in a tradition of philosophical ‘dynamics’ stemming from Leibniz, which is examined in part one. The three parts of the thesis proceed chronologically through the Kantian oeuvre. Part one reconstructs the historical context of Leibnizian and Newtonian conceptions of force, and presents a narrative of the employment of force in Kant’s pre-critical writings, in their relation to the broad problematic of Leibniz’s dynamics. Part two explores the account of physical and psychological forces, and the common, ontological notion of force, in the major critical-period discussions. Part three presents the late works, namely the third Critique and the Opus postumum, as a ‘philosophy of force’, in which force, with all its necessary ambiguities, plays central roles in Kant’s late systematising endeavours. I conclude that the perspective of this thesis makes possible a new understanding of the nature and unity of Kant’s philosophical project. (shrink)

It is often claimed (most recently by Michael Friedman) that Kant intended to justify Newton’s most fundamental claims expressed in the Principia, such as his laws of motion and the law of universal gravitation. In this article, I argue that the differences between Newton’s laws of motion and Kant’s laws of mechanics are not superficial or merely apparent. Rather, they reflect fundamental differences in their respective projects. This point can be seen especially clearly by considering the nature of the various (...) projects undertaken in Germany prior to Kant that discuss the laws of motion. Wolff and his followers qua metaphysicians were especially interested in providing nonempirical justifications of their laws of motion as well as an intelligible account of the fundamental properties of bodies in terms of substance, accident, and force. Maupertuis and Euler, despite often being seen as Newtonians, both drew on traditions other than Newton’s. Physics textbooks (by figures such as Erxleben, Karsten, ‘s Gravesande, and Musschenbroek) vary considerably in their aims, but in none of these cases is Newton’s main argument of the Principia presented. In light of the fact that these projects are distinct in significant ways from Newton’s project, the differences between Newton’s laws of motion and Kant’s laws of mechanics are most likely not merely apparent but reflect the fact that Kant, too, was pursuing a project fundamentally distinct from Newton’s. (shrink)

By the time of the Leibniz-Clarke correspondence of 1716 the Newtonian and Leibnizian systems of natural philosophy had reached maturity. Each system consisted of different physical as well as metaphysical principles which, taken together, formed a world view. At the time of their famous debates, Leibniz at 70 and Newton at 74, the founders of two highly developed scientific philosophies, were struggling to establish and defend the ontological and mechanical bases of differing bodies of organized knowledge.

I explain Kant’s critique of Leibniz’s rejection of real opposition in the Amphiboly in the context of Kant’s pre-Critical writings on vis viva and negative magnitudes and his Metaphysical Foundations of Natural Science. Properly contextualized in terms of the vis viva controversy, I argue, Kant’s arguments against Leibniz succeed, even though they are laden with theoretical inconsistencies and operate under false physical premises.

Euler’s ‘On the force of percussion and its true measure’, published in 1746, shows that not only had the issue of vis viva not been settled, but that the concepts of inertia and even force were still very much up for grabs. This paper details Euler’s treatment of the vis viva problem. Within those details we find differences between his physics and that of Newton, in particular the rejection of empty space and reduction of all forces to the operation of (...) inertia through contact. One can further see how Euler’s philosophy of science embraced explanation through mechanisms and equilibrium conditions.Keywords: Leonhard Euler; Vis viva; Equlibrium; Mechanics; Eighteenth century. (shrink)

The purpose of this dissertation is to defend Pierre Fermat and Gottfried Wilhelm Leibniz against the charge of error made against them by Pierre Maupertuis that they errantly applied final causes to physics. This charge came in Maupertuis’ 1744 speech to the Paris Academy of Sciences, later published in different versions, entitled Accord Between Different Laws Which at First Seemed Incompatible. It is in this speech that Maupertuis lays claim to one of the most important discoveries in the history of (...) physics and science, The Principle of Least Action. From the date of this speech up until the end of the twentieth century, Maupertuis was credited with this discovery. Fermat discovered least time in optical physics, and Leibniz co-discovered infinitesimal calculus. When the credited discoverer of least action in physics accuses the discoverer of least time in optics and the co-discoverer of infinitesimal calculus of error before and audience of mathematicians, physicists and scientists, it is an event that calls out for investigation. The idea of final causes in physics is the idea that bodies move for an end purpose. During the early modern period, this challenged the intellectual establishment of the day with the idea of thinking in nature. The question which fueled the research for this dissertation is why such a man would accuse two other prominent intellects with such an unprovable metaphysical assumption. The research for this project started with a study of the positions of all three of these men regarding final causes in physics. The second phase was to research the historical context in which Accord Between Different Laws Which at First Seemed Incompatible was written and delivered. This context included the life of Maupertuis as member of the Paris Academy of Sciences and as later President of the Berlin Academy of Sciences. It also included the workings of three highly competitive, state funded, academies of science in Berlin, London and Paris. Research showed that no formal positions were held on the subject of final causes by either Maupertuis or Fermat. Only Leibniz demonstrated an established and well thought out position on the subject. Research did reveal the story of an ambitious man in Maupertuis, who made it the fulfillment of his ambition to rise in the ranks of math and science within the academies and establish himself as an intellectual great in European culture. Consequently, the life and career of Maupertuis illustrates the sociological dimension of scientific achievement. Accord Between Different Laws Which at First Seemed Incompatible turned out to be a politically calculated speech delivered for the purpose of career advancement. In 1744, Maupertuis was being considered by the King of Prussia, Frederick the Great, and the leadership of the Berlin Academy of Science for the presidency of that institution. Maupertuis knew this. Therefore, the work must be interpreted in this context. Consequently, the charge of error against Fermat and Leibniz by Maupertuis must be interpreted likewise. Discovery was made in contextual and Leibnizian research that Maupertuis was aware of Leibniz’s idea of action from 1738 on, and knowingly claimed to have discovered a generalized notion of action in physics which was not his. It is the story of ambition clouding human judgment. The Leibnizians attacked Maupertuis on this matter, led by a member of the Berlin Academy named Samuel Konig. In the “Konig Affair”, Konig accused Maupertuis of what is essentially plagiarism, and Maupertuis countered with charging Konig with forgery for claiming to have in his possession a letter from Leibniz to Jacob Hermann demonstrating Leibniz’s knowledge of least action. Maupertuis buries Konig in legal proceedings, but loses his reputation in the process. During the final stages of the Konig affair, Maupertuis admits to Patrick d’Arcy, a member of the Paris academy, that he had used Leibniz’s theory of action. Having lost his effective leadership as President of the Berlin Academy, Maupertuis spends the last years of his life in his native France without ever relinquishing his title and office. When at first examining the charge of error, the immediate notion is that this is a cause and effect argument. It appears to be an argument about the order of metaphysics before physics. This turns out not to be the case. Maupertuis agrees with Fermat and Leibniz at every turn. The charge is all about career success. (shrink)