In his monumental 1687 work, _Philosophiae Naturalis Principia Mathematica_, known familiarly as the _Principia_, Isaac Newton laid out in mathematical terms the principles of time, force, and motion that have guided the development of modern physical science. Even after more than three centuries and the revolutions of Einsteinian relativity and quantum mechanics, Newtonian physics continues to account for many of the phenomena of the observed world, and Newtonian celestial dynamics is used to determine the orbits of our space vehicles. (...) This authoritative, modern translation by I. Bernard Cohen and Anne Whitman, the first in more than 285 years, is based on the 1726 edition, the final revised version approved by Newton; it includes extracts from the earlier editions, corrects errors found in earlier versions, and replaces archaic English with contemporary prose and up-to-date mathematical forms. Newton's principles describe acceleration, deceleration, and inertial movement; fluid dynamics; and the motions of the earth, moon, planets, and comets. A great work in itself, the _Principia_ also revolutionized the methods of scientific investigation. It set forth the fundamental three laws of motion and the law of universal gravity, the physical principles that account for the Copernican system of the world as emended by Kepler, thus effectively ending controversy concerning the Copernican planetary system. The translation-only edition of this preeminent work is truly accessible for today's scientists, scholars, and students. (shrink)

Isaac Newton's Scientific Method examines Newton's argument for universal gravity and his application of it to resolve the problem of deciding between geocentric and heliocentric world systems by measuring masses of the sun and planets. William L. Harper suggests that Newton's inferences from phenomena realize an ideal of empirical success that is richer than prediction. Any theory that can achieve this rich sort of empirical success must not only be able to predict the phenomena it purports (...) to explain, but also have those phenomena accurately measure the parameters which explain them. Harper explores the ways in which Newton's method aims to turn theoretical questions into ones which can be answered empirically by measurement from phenomena, and to establish that propositions inferred from phenomena are provisionally accepted as guides to further research. This methodology, guided by its rich ideal of empirical success, supports a conception of scientific progress that does not require construing it as progress toward Laplace's ideal limit of a final theory of everything, and is not threatened by the classic argument against convergent realism. Newton's method endorses the radical theoretical transformation from his theory to Einstein's. Harper argues that it is strikingly realized in the development and application of testing frameworks for relativistic theories of gravity, and very much at work in cosmology today. (shrink)

Isaac Newton's Scientific Method examines Newton's argument for universal gravity and his application of it to resolve the problem of deciding between geocentric and heliocentric world systems by measuring masses of the sun and planets. William L. Harper suggests that Newton's inferences from phenomena realize an ideal of empirical success that is richer than prediction. Any theory that can achieve this rich sort of empirical success must not only be able to predict the phenomena it purports (...) to explain, but also have those phenomena accurately measure the parameters which explain them. Harper explores the ways in which Newton's method aims to turn theoretical questions into ones which can be answered empirically, by measurement from phenomena, and to establish that propositions inferred from phenomena are provisionally accepted as guides to further research. This methodology, guided by its rich ideal of empirical success, supports a conception of scientific progress that does not require construing it as progress toward Laplace's ideal limit of a final theory of everything, and is not threatened by the classic argument against convergent realism. Newton's method endorses the radical theoretical transformation from his theory to Einstein's. Harper argues that it is strikingly realized in the development and application of testing frameworks for relativistic theories of gravity, and very much at work in cosmology today. (shrink)

A striking feature of Newton’s thought is the very broad reach of his empiricism, potentially extending even to immaterial substances, including God, minds, and should one exist, a non-perceiving immaterial medium. Yet Newton is also drawn to certain metaphysical principles—most notably the principle that matter cannot act where it is not—and this second, rationalist feature of his thought is most pronounced in his struggle to discover ‘gravity’s cause’. The causal problem remains vexing, for he neither invokes primary (...) causation, nor accepts action at a distance by locating active powers in matter. To the extent that he is drawn to metaphysical principles, then, the causal problem is that of discovering some non-perceiving immaterial medium. Yet Newton’s thought has a third striking feature, one with roots in the other two: he allows that substances of different kinds might simultaneously occupy the very same region of space. I elicit the implications of these three features. For Newton to insist upon all three would transform the causal question about gravity into an insoluble problem about apportioning active powers. More seriously, it would undermine his means of individuating substances, provoking what I call ‘Newton’s Substance Counting Problem’. (shrink)

A striking feature of Newton’s thought is the very broad reach of his empiricism, potentially extending even to immaterial substances, including God, minds, and should one exist, a non-perceiving immaterial medium. Yet Newton is also drawn to certain metaphysical principles—most notably the principle that matter cannot act where it is not—and this second, rationalist feature of his thought is most pronounced in his struggle to discover ‘gravity’s cause’. The causal problem remains vexing, for he neither invokes primary (...) causation, nor accepts action at a distance by locating active powers in matter. To the extent that he is drawn to metaphysical principles, then, the causal problem is that of discovering some non-perceiving immaterial medium. Yet Newton’s thought has a third striking feature, one with roots in the other two: he allows that substances of different kinds might simultaneously occupy the very same region of space. I elicit the implications of these three features. For Newton to insist upon all three would transform the causal question about gravity into an insoluble problem about apportioning active powers. More seriously, it would undermine his means of individuating substances, provoking what I call ‘Newton’s Substance Counting Problem’. (shrink)

One prominent criticism of Newtonianism held that gravitational attraction is an occult quality. The charge, pressed most forcefully by Leibniz, claims that Newton had abandoned the intelligibility of mechanism and allowed for an unexplained and inexplicable force in nature. This paper focuses on one of Newton’s replies to this accusation: his claim that gravitation is no more mysterious than phenomena like inertia and impenetrability. I argue that we can understand and motivate this Newtonian position by looking at the (...) account of material substance developed in Newton’s early manuscript essay De gravitatione. This account makes clear Newton’s sensitivity to the explanatory limits of mechanism. Newton was perceptive in noting that while the mechanical philosophy sought to provide explanations in terms of matter and motion, it failed to explain matter and motion themselves. This sheds light on the motivations behind the theory of bodies in De gravitatione. And it helps to explain why he was so unmoved by what many saw as a serious challenge to his theory of gravity. (shrink)

ArgumentIt is argued that the sensorium of God was introduced into theQuaestionesadded to the end of Newton’sOptice(1706) as a way of answering objections that Newton had failed to provide a causal account of gravity in thePrincipia. The discussion of God’s sensorium indicated that gravity must be caused by God’s will. Newton did not leave it there, however, but went on to show how God’s will created active principles as secondary causes of gravity. There was (...) nothing unusual in assuming that God, acting as the First Cause, operated in nature by means of secondary causes; but it was unusual to devote as much time to discussing God’s precise role as to discussing the secondary causes themselves. It is contended that Newton felt the need to do this to persuade readers that what might seem like a second cause that could not possibly work could be made to work by the omnipotent God. (shrink)

This paper is a critical response to Hylarie Kochiras’ “Gravity and Newton’s substance counting problem,” Studies in History and Philosophy of Science 40 267–280. First, the paper argues that Kochiras conflates substances and beings; it proceeds to show that Newton is a substance monist. The paper argues that on methodological grounds Newton has adequate resources to respond to the metaphysical problems diagnosed by Kochiras. Second, the paper argues against the claim that Newton is committed to (...) two speculative doctrines attributed to him by Kochiras and earlier Andrew Janiak: i) the passivity of matter and ii) the principle of local causation. Third, the paper argues that while Kochiras’ arguments about Newton’s metaphysical commitments are mistaken, it qualifies the characterization of Newton as an extreme empiricist as defended by Howard Stein and Rob DiSalle. In particular, the paper shows that Newton’s empiricism was an intellectual and developmental achievement that built on non trivial speculative commitments about the nature of matter and space.Keywords: Newton; Substance; Action at a distance; Space; Matter; Empiricism. (shrink)

In this discussion paper, I seek to challenge Hylarie Kochiras’ recent claims on Newton’s attitude towards action at a distance, which will be presented in Section 1. In doing so, I shall include the positions of Andrew Janiak and John Henry in my discussion and present my own tackle on the matter . Additionally, I seek to strengthen Kochiras’ argument that Newton sought to explain the cause of gravity in terms of secondary causation . I also provide (...) some specification on what Kochiras calls ‘Newton’s substance counting problem’ . In conclusion, I suggest a historical correction .Keywords: Isaac Newton ; Action at a distance; Cause of gravity; Fourth letter to Bentley. (shrink)

This paper is in three sections. The first establishes that Newton, in spite of a well-known passage in a letter to Richard Bentley of 1692, did believe in action at a distance. Many readers may see this merely as an act of supererogation, since it is so patently obvious that he did. However, there has been a long history among Newton scholars of allowing the letter to Bentley to over-ride all of Newton’s other pronouncements in favour of (...) action at a distance, with devastating effects on our understanding of related aspects of his physics and his theology. Furthermore, this misconceived scholarly endeavour shows no sign of abating. The second section then offers a historical reconstruction, based on Newton’s writings, of how, when and why he began to accept actions at a distance and make them one of the cornerstones of his physics. Finally, using this chronological account of Newton’s use of actions at a distance, the paper re-assesses the claims of B. J. T. Dobbs that Newton’s important manuscript, De gravitatione et aequipondio fluidorum, was written, not in the late 1660s or early 1670s as was previously supposed, but during the composition of the Principia, in 1684 or 1685.Keywords: Isaac Newton; Action-at-a-distance; Gravity; Force; Aether; Attraction. (shrink)

In this paper I clarify what Newton could have meant when he insisted that gravity is a real force. I interpret Newton’s speculative treatment of gravity as a relational, accidental quality of matter that arises through what Newton calls “the shared action” of two bodies. I argue that when Newton drafted the first edition of the Principia in the mid 1680s, he thought that (at least a part of) the cause of gravity is (...) the disposition inherent in any individual body, but that the force of gravity is the actualization of that disposition; a necessary condition for the actualization of the disposition is the actual obtaining of a relation between two bodies having the disposition. The cause of gravity is not essential to matter because God could have created matter without that disposition. Nevertheless, at least a part of the cause of gravity inheres in individual bodies and were there one body in the universe it would inhere in that body. On the other hand, the force of gravity is neither essential to matter nor inherent in matter, because (to repeat) it is the actualization of a shared disposition. A lone part-less particle would, thus, not generate a gravity field. (shrink)

We construct a notion of teleparallelization for Newton-Cartan theory, and show that the teleparallel equivalent of this theory is Newtonian gravity; furthermore, we show that this result is consistent with teleparallelization in general relativity, and can be obtained by null-reducing the teleparallel equivalent of a five-dimensional gravitational wave solution. This work thus strengthens substantially the connections between four theories: Newton-Cartan theory, Newtonian gravitation theory, general relativity, and teleparallel gravity.

Not a full treatment of Newton’s scientific method, this book discusses his optical research only in passing (342–43). Its subtitle better indicates its scope: it focuses narrowly on the argument for universal gravitation in Book III of the Principia. The philosophical project is to set out an “ideal of empirical success” realized by the argument. Newton claims his method is to “deduce” propositions “from phenomena.” On Harper’s interpretation Newton’s phenomena are patterns of data, which are used to (...) measure “parameters” by which the theory explains them. An example is Kepler’s Area Rule. Its fit to the data confirms the hypothesis that the force maintaining a body in orbit is directed toward the .. (shrink)

In this paper I interpret Newton’s speculative treatment of gravity as a relational, accidental property of matter that arises through what Newton calls “the shared action” of two bodies of matter. In doing so, I expand and extend on a hint by Howard Stein. However, in developing the details of my interpretation I end up disagreeing with Stein’s claim that for Newton a single body can generate a gravity/force field. I argue that when Newton (...) drafted the first edition of the Principia in the mid 1680s, he thought that (at least a part of) the cause of gravity is the disposition inherent in any individual body, but that the force of gravity is the actualization of that disposition; a necessary condition for the actualization of the disposition is the actual obtaining of a relation between two bodies having the disposition. The cause of gravity is not essential to matter because God could have created matter without that disposition. Nevertheless, at least a part of the cause of gravity inheres in individual bodies and were there one body in the universe it would inhere in that body. On the other hand, the force of gravity is neither essential to matter nor inherent in matter, because (to repeat) it is the actualization of a shared disposition. A lone part-less particle would, thus, not generate a gravity field. Seeing this allows us to helpfully distinguish among a) accepting gravity as causally real; b) the cause(s) (e.g. the qualities of matter) of the properties of gravity; c) making claims about the mechanism or medium by which gravity is transmitted. This will help clarify what Newton could have meant when he insisted that gravity is a real force. I present my argument in opposition to Andrew Janiak’s influential and fine 2007 paper. Along the way, I call attention to my disagreement with Janiak on a number of secondary issues (e.g. Janiak’s attribution to Newton of a distinction between ‘local’ and ‘distant’ action; Janiak’s reading of the “Letter to Bentley,” etc). (shrink)

Samuel Clarke is best known to historians of science for presenting Isaac Newton’s views to a wider audience, especially in his famous correspondence with G. W. Leibniz. Clarke’s independent writings, however, reveal positions that do not derive from, and do not coincide with, Newton’s. This essay compares Clarke’s and Newton’s ideas on the cause of gravity, with a view to clarifying our understanding of Newton’s views. There is evidence to suggest that Newton believed God (...) was directly responsible for gravity, and this interpretation has been promoted by a number of scholars. By comparing Newton’s views with those of Clarke, however, it can be seen that Newton did not subscribe to the kind of occasionalist approach to gravity that Clarke developed. Clarke insisted that matter was categorically incapable of being endowed with powers or forces and that therefore what looks like gravitational attraction has to be performed directly by God or by angels. By comparing Clarke’s pronouncements with Newton’s, it becomes clear that Newton adopted the more standard line: that the first cause, God, operated in nature through secondary causes and that gravitational attraction was just such a secondary (albeit occult) cause. (shrink)

In this article, we document how, in the public arena, British readers of the first edition of Isaac Newton's Philosophiae naturalis principia mathematica (1687) tried to make sense of the relation between gravity, matter, and divine and natural causation—an issue on which Newton had remained entirely silent in the first edition of the Principia. We show that readers attached new meanings to the Principia so that parts of it migrated to a different intellectual debate. It will be (...) shown that one particular result Newton obtained in the Principia, namely the rejection of a vacuum in Corollary 3 to Proposition 6 in Book 3, was the most important locus in debates on the relation between gravity, matter, and causation. (shrink)

It is here argued that Halley's comet had a more pivotal role than has hitherto been believed in triggering Newton's acceptance of the law of gravity, dispelling his belief in Descartes' theory of vortices. It is found that historians have been unduly prone to credit Newton with dynamical insights at an earlier date than is warranted by the historical documents. A more convincing account of the transition from the period of Newton's alchemical researches of the 1670s (...) to that of his dynamical insights in the 1680s thereby becomes feasible. Acceptance of a principle of rectilinear inertia was a precondition for formulating the law. (shrink)

The gravity-related model of spontaneous wave function collapse, a longtime hypothesis, damps the massive Schrödinger Cat states in quantum theory. We extend the hypothesis and assume that spontaneous wave function collapses are responsible for the emergence of Newton interaction. Superfluid helium would then show significant and testable gravitational anomalies.

This is a critical review of the book Variational Approach to Gravity Field Theories - From Newton to Einstein and Beyond (2017), written by the Italian astrophysicist Alberto Vecchiato. In his work, Vecchiato shows that physics, as we know it, can be built up from simple mathematical models that become more complex step by step by gradually introducing new principles. The reader is invited to follow the steps that lead from classical physics to relativity and to understand how (...) this happens and why. Moreover, while presenting the variational approach to gravity field theories in a clear and elegant manner, Vecchiato shows a constant worry in leading the readers in such a way that they understand the relevance of what the author considers to be the most powerful technique and unifying concept of theoretical physics - and how it works. Each chapter is enriched with exercises, of which a step-by-step solution is offered, so that the reader can gain a real insight into the topic presented and follow the reading as fruitfully as possible. The most innovative aspect of the book, however, is not the rigorousness and the clarity of the treatment of the variational approach, but rather the point of view that Vecchiato keeps and that the reader is led to endorse too: physics is a human enterprise, prone to error and open to improvement, and not a complete and definite system of truths about our world. (shrink)

This paper considers Newton’s position on gravity’s cause, both conceptually and historically. With respect to the historical question, I argue that while Newton entertained various hypotheses about gravity’s cause, he never endorsed any of them, and in particular, his lack of confidence in the hypothesis of robust and unmediated distant action by matter is explained by an inclination toward certain metaphysical principles. The conceptual problem about gravity’s cause, which I identified earlier along with a deeper (...) problem about individuating substances, is that a decisive conclusion is impossible unless certain speculative aspects of his empiricism are abandoned. In this paper, I situate those conceptual problems in Newton’s natural philosophy. They arise from ideas that push empiricism to potentially self-defeating limits, revealing the danger of allowing immaterial spirits any place in natural philosophy, especially spatially extended spirits supposed capable of co-occupying place with material bodies. Yet because their source ideas are speculative, Newton’s method ensures that these problems pose no threat to his rational mechanics or the profitable core of his empiricism. They are easily avoided by avoiding their source ideas, and when science emerges from natural philosophy, it does so with an ontology unencumbered by immaterial spirits. (shrink)

This paper considers Newton’s position on gravity’s cause, both conceptually and historically. With respect to the historical question, I argue that while Newton entertained various hypotheses about gravity’s cause, he never endorsed any of them, and in particular, his lack of confidence in the hypothesis of robust and unmediated distant action by matter is explained by an inclination toward certain metaphysical principles. The conceptual problem about gravity’s cause, which I identified earlier along with a deeper (...) problem about individuating substances, is that a decisive conclusion is impossible unless certain speculative aspects of his empiricism are abandoned. In this paper, I situate those conceptual problems in Newton’s natural philosophy. They arise from ideas that push empiricism to potentially self-defeating limits, revealing the danger of allowing immaterial spirits any place in natural philosophy, especially spatially extended spirits supposed capable of co-occupying place with material bodies. Yet because their source ideas are speculative, Newton’s method ensures that these problems pose no threat to his rational mechanics or the profitable core of his empiricism. They are easily avoided by avoiding their source ideas, and when science emerges from natural philosophy, it does so with an ontology unencumbered by immaterial spirits. (shrink)

: Newton's critics argued that his treatment of gravity in the Principia saddles him with a substantial dilemma. If he insists that gravity is a real force, he must invoke action at a distance because of his explicit failure to characterize the mechanism underlying gravity. To avoid distant action, however, he must admit that gravity is not a real force, and that he has therefore failed to discover the actual cause of the phenomena associated with (...) it. A reinterpretation of Newton's distinction between the "mathematical" and the "physical" treatment of force indicates how he can reject each horn of this dilemma. (shrink)

Newton published his deduction of universal gravity in Principia (first ed., 1687). To establish the universality (the particle-to-particle nature) of gravity, Newton must establish the additivity of mass. I call ‘additivity’ the property a body's quantity of matter has just in case, if gravitational force is proportional to that quantity, the force can be taken to be the sum of forces proportional to each particle's quantity of matter. Newton's argument for additivity is obscure. I analyze (...) and assess manuscript versions of Newton's initial argument within his initial deduction, dating from early 1685. Newton's strategy depends on distinguishing two quantities of matter, which I call ‘active’ and ‘passive’, by how they are measured. These measurement procedures frame conditions on the additivity of each quantity so measured. While Newton has direct evidence for the additivity of passive quantity of matter, he does not for that of the active quantity. Instead, he tries to infer the latter from the former via conceptual analyses of the third law of motion grounded largely on analogies to magnetic attractions. The conditions needed to establish passive additivity frustrate Newton's attempted inference to active additivity. (shrink)

The relation between Ernst Mach and Albert Einstein is probably one of the most debated issues in the history of twentieth century physics. For many physicists general relativity is the paradigm ofhow a mature theory should look. This opinion was supported by philosophers, in particular logical empiricists, to whom general relativity was the main touchstone of their principles of theory formation. Mach’s principle penetrates all three domains. Einstein’s first formulation of it in 1918 read: “The G-field is without remainder determined (...) by the masses of the bodies. Since mass and energy are... the same.. .this therefore entails that the G-field be condi tioned and determined by the energy tensor”. (shrink)

Relativizing Newton" is a first step towards a simple and beautiful theory of everything. The theory, termed "Information Relativity" (IR) takes a novel approach to physics that overlooks all post-Newtonian physics. It stands on the shoulders of Newtonian dynamics, but modifies it by accounting for the time-travel of information from one reference-frame to another, a fact which somehow was ignored by Galileo Galilee and Isaac Newton, and which remained ill-treated by the all post-Newtonian theories, including Einstein's relativity and (...) quantum theories. Except for the aforementioned correction of classical physics, IR has no axiomatic presumptions, nor arbitrary free parameters. Astonishingly, accounting for the aforementioned delays in information results in a set of simple and beautiful transformations, which explain and predict a great deal of physical phenomena. Most importantly, IR's transformations reveal the mysteries of dark matter, dark energy, and gravity. They also provide a unifying platform for the physics of the too-big (astrophysics and cosmology), and the too-small (small particles dynamics and quantum mechanics). The phenomena explained and predicted successfully by IR include The Michelson-Morley's null-result, "time-dilation" of decaying muons, the neutrino velocities measured by OPERA and other collaborations, particle diffraction in the double-slit experiment, Sagnac Effects, the quantization of orbits in Bohr's hydrogen atom, entanglement, quantum criticality, confinement, asymptotic freedom, solar light bending, gravitational redshift, the Pioneer anomaly, dark matter in galaxies, and the Schwarzschild's black hole. (shrink)

This article investigates the relationship between Hume’s causal philosophy and Newton ’s philosophy of nature. I claim that Newton ’s experimentalist methodology in gravity research is an important background for understanding Hume’s conception of causality: Hume sees the relation of cause and effect as not being founded on a priori reasoning, similar to the way that Newton criticized non - empirical hypotheses about the properties of gravity. However, according to Hume’s criteria of causal inference, the (...) law of universal gravitation is not a complete causal law, since it does not include a reference either to contiguity or to temporal priority. It is still argued that because of the empirical success of Newton ’s theory—the law is a statement of an exceptionless repetition—Hume gives his support to it in interpreting gravity force instrumentally as if it bore a causal relation to motion. (shrink)

Newton's Philosophiae Naturalis Principia Mathematica provides a coherent and deductive presentation of his discovery of the universal law of gravitation. It is very much more than a demonstration that 'to us it is enough that gravity really does exist and act according to the laws which we have explained and abundantly serves to account for all the motions of the celestial bodies and the sea'. It is important to us as a model of all mathematical physics.Representing a decade's (...) work from a distinguished physicist, this is the first comprehensive analysis of Newton's Principia without recourse to secondary sources. Professor Chandrasekhar analyses some 150 propositions which form a direct chain leading to Newton's formulation of his universal law of gravitation. In each case, Newton's proofs are arranged in a linear sequence of equations and arguments, avoiding the need to unravel the necessarily convoluted style of Newton's connected prose. In almost every case, a modern version of the proofs is given to bring into sharp focus the beauty, clarity, and breath-taking economy of Newton's methods.Subrahmanyan Chandrasekhar is one of the most reknowned scientists of the twentieth century, whose career spanned over 60 years. Born in India, educated at the University of Cambridge in England, he served as Emeritus Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics at the University of Chicago, where he has was based from 1937 until his death in 1996. His early research into the evolution of stars is now a cornerstone of modern astrophysics, and earned him the Nobel Prize for Physics in 1983. Later work into gravitational interactions between stars, the properties of fluids, magnetic fields, equilibrium ellipsoids, and black holes has earned him awards throughout the world, including the Gold Medal from the Royal Astronomical Society in London, the National Medal of Science in the United States, and the Copley Medal from the Royal Society. His many publications include Radiative transfer, Hydrodynamic and hydromagnetic stability, and The mathematical theory of black holes, each being praised for its breadth and clarity. Newton's Principia for the common reader is the result of Professor Chandrasekhar's profound admiration for a scientist whose work he believed is unsurpassed, and unsurpassable. (shrink)