Advertisement

Abstract

The precise nature of the force of gravitational attraction was always problematic for Isaac Newton. As is well known he was forced by the criticism of Leibniz to acknowledge in the General Scholium to the Principia mathematica that he did not know the cause of gravity. Making a virtue out of a necessity, he insisted that he was not interested in feigning explanatory hypotheses, being perfectly content to show “that gravity does really exist and act according to the laws which we have explained.” Elsewhere, however, as is also well known, Newton did try out various explanatory hypotheses. Essentially, Newton’s speculations derived from four earlier traditions with which he was familiar. Drawing upon the Neoplatonic tradition of light metaphysics, he suggested that light might combine with matter to give it various active powers; the alchemical tradition linked ideas of light with ideas of an active spirit, present in all things, which again might be said to give rise to various unceasing activities of matter. This active spirit, in its turn, could be linked to more recent ideas, developed in the new mechanical philosophy, in which an all pervasive aether was used as a medium of transmitting impulse from one part of the universe to another. Newton’s own aether speculations were by no means purely mechanistic, since his aether consisted of particles held apart from one another, and from particles of other matter, by repulsive forces operating between them, but they clearly owed something to the mechanical as well as the alchemical traditions. The fourth tradition was Christian theology: gravitational attraction being held to be brought about by God.1

Keywords

Active Principle Scientific Revolution Gravitational Attraction Universal Gravitation Mutual Contact 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Notes

  1. 1.
    The role of light metaphysics in Newton’s thinking has not received separate treatment but see Eman McMullin, Newton on Matter and Activity (Notre Dame and London, 1978), pp. 84–96. The role of light is also alluded to in some of the discussions of Newton’s alchemy, particularly when discussing his alchemical treatise, ‘On the Vegetation of Metals’, and his ‘Hypothesis explaining the Properties of Light’ of 1675. See, for examples, P. M. Rattansi, ‘Newton’s Alchemical Studies’, and R. S. Westfall, ‘Newton and the Hermetic Tradition’, both in A. G. Debus (ed.), Science, Medicine and Society in the Renaissance (New York, 1972), pp. 167–82 and 183–98; and J. E. McGuire, ‘Transmutation and Immutability: Newton’s Doctrine of Physical Qualities’, Amhix 14 (1967); 69–95. On Newton’s aether speculations see Henry E. Guerlac, ‘Newton’s Optical Aether’, Notes and Records of the Royal Society of London 22 (1967): 45–57; P. M. Harman, ‘Ether and Imponderables’, in G. N. Cantor and M. J. S. Hodge (eds), Conceptions of Ether (Cambridge, 1981), pp. 61–83; and R. W. Home, ‘Newton on Electricity and the Aether’, in Zev Bechler (ed.), Contemporary Newtonian Research (Dordrecht, 1982), pp. 191–213. Newton’s pronouncements on gravity as an effect brought about by God are discussed in R. S. Westfall, Never at Rest: A Biography of Isaac Newton (Cambridge, 1980), pp. 505–11. Westfall’s biography should be consulted for excellent discussions of all the foregoing issues as well (the index is excellent). Isaac Newton, Mathematical Principles of Natural Philosophy, translated by Andrew Motte, revised by Florian Cajori (Berkeley, 1946), p. 547.Google Scholar
  2. 2.
    A. Rupert Hall, The Scientific Revolution (London, 1962), p. 273; idem, The Revolution in Science, 1500–1750 (London, 1983), p. 323; idem, Henry More: Magic, Religion and Experiment (Oxford, 1990), p. 231, 232, 238, 240. Although the first two of these books were intended for undergraduate audiences, I have included them in my survey because that will have gained them a certain amount of influence in the field.Google Scholar
  3. 3. A
    lexandre Koyré, ‘Gravity an Essential Property of Matter?’, in idem, Newtonian Studies (London, 1965), pp. 149–63, see p. 149, 152, 149.Google Scholar
  4. 4. I.
    B. Cohen, ‘Newton’s Third Law and Universal Gravitation’, Journal of the History of Ideas, 48 (1987): 571–93, pp. 587–88, 588–89. This article also appears in P. B. Scheurer and G. Debrock (eds), Newton’s Scientific and Philosophical Legacy (Dordrecht, 1988), pp. 25–53.Google Scholar
  5. 5. E
    man McMullin, Newton on Matter and Activity (see note 1), p. 104.Google Scholar
  6. 6.M
    cMullin, Newton on Matter and Activity (see note 1), pp. 105–6; Hall, Henry More (see note 2), p. 232.Google Scholar
  7. 7.Is
    aac Newton, Four Letters from Sir Isaac Newton to Doctor Bentley containing some Arguments in Proof of a Deity (London, 1756), Letter II, p. 20. This letter is dated January 17 1692/3. The letters are conveniently reprinted in I. B. Cohen (ed.), Isaac Newton’s Papers & Letters on Natural Philosophy, 2nd edition (Cambridge, Mass., and London, 1978), pp. 279–312. See, p. 298. Henceforward I will refer to this edition, as Papers & Letters, and give page numbers of the original edition in brackets.Google Scholar
  8. 8. P
    apers & Letters, pp. 302–3 (25–6). This letter is dated February 25, 1692/3.Google Scholar
  9. 9.Is
    aac Newton, Opticks, or A Treatise of the Reflections. Refractions, Inflections & Colours of Light, based on the 4th edition London, 1730 (New York, 1979), pp. 370–1, 375–6.Google Scholar
  10. 10.
    McMullin, Newton on Matter and Activity (see note 1), p. 53.Google Scholar
  11. 11.
    R. S. Westfall, ‘The Rise of science and the Decline of Orthodox Christianity: A Study of Kepler, Descartes, and Newton’, in D. C. Lindberg and R. L. Numbers (eds), God and Nature: Historical Essays on the Encounter between Christianity and Science (Berkeley, 1986), pp. 218–37, especially p. 233; B. J. T. Dobbs, ‘Newton’s Alchemy and his “Active Principle” of Gravitation’, in P.B. Scheurer and G. Debrock (eds), Newton’s Scientific and Philosophical Legacy (Dordrecht, 1988), pp. 55–80, p. 74. These are discussed more fully below.Google Scholar
  12. 12.
    Richard Bentley, A Confutation of Atheism from the Origin and Frame of the World, Part II (London, 1693), pp. 331–2 (19–20). This is conveniently reprinted in Papers & Letters and I will refer to that edition henceforth, giving page numbers of the original edition in brackets.Google Scholar
  13. 13.
    Papers & Letters, p. 302 (25).Google Scholar
  14. 14.
    Papers & Letters, p. 339 (27).Google Scholar
  15. 15.
    Koyré, ‘Gravity an Essential Property of Matter?’ (see note 3), p. 149. Perry Miller, ‘Bentley and Newton’, in Papers & Letters, pp. 271–78.Google Scholar
  16. 16.
    Papers & Letters, p. 341 (29). See also, pp. 332–3 (20–1), and p. 363 (p. 11 in Part III, the Eighth Lecture).Google Scholar
  17. 17.
    Papers & Letters, p. 340 (28). Bentley, Letter to Newton, 18 February, 1692/3, see H.W. Turnbull et al. (eds), The Correspondence of Isaac Newton, 7 vols. (Cambridge, 1959–71), Vol. 3, pp. 246–253, p. 249.Google Scholar
  18. 18.
    For discussions of Newton’s voluntarism see Francis Oakley ‘Christian Theology and the Newtonian Science: The Rise of the Concept of Laws of Nature’, Church History 30 (1961): 433–57; and J. E. McGuire, ‘Force, Active Principles and Newton’s Invisible Realm’, Ambix 15 (1968): 154–208.Google Scholar
  19. 19.
    Newton, Opticks (see note 9), pp. 400–01.Google Scholar
  20. 20.
    Newton, Opticks (see note 9), pp. 404–5.Google Scholar
  21. 21.
    Newton, Principia (see note 1), p. 399.Google Scholar
  22. 22.
    This is a difficult point to get across. Consider the phenomena of shadows. Would it not seem misleading to describe shadows as immaterial entities? The unenlightened might jump to the conclusion that shadows must, therefore, be spiritual beings. To avoid this, we might prefer to consider them to be material phenomena, even though they are not composed of matter, because they are produced by the behaviour of matter and cannot exist without material objects to bring them into existence. Perhaps there should be a third category for referring to such epiphenomena of matter, but in the meantime, whether shadows are material or immaterial must be left to the consideration of individuals. Another point to bear in mind when dealing with historical concepts of matter and spirit is that the distinction between material and immaterial in seventeenth-century thought was by no means always so clear cut as it was in fully committed philosophical dualists, such as Descartes or Henry More. The status of light, for example, on a spectrum from material to immaterial never achieved a consensus, and J. E. McGuire in his detailed studies of Newton’s concept of force certainly concluded that Newtonian forces and other active principles were part of an “invisible realm” which could not definitively be said to be either corporeal or incorporeal, but was rather something in between. See McGuire, ‘Force, Active Principles and Newton’s Invisible Realm’ (see note 18).Google Scholar
  23. 23.
    R. S. Westfall, Force in Newton’s Physics: The Science of Dynamics in Seventeenth Century (London and New York, 1971), p. 396. Westfall, ‘The Rise of science and the Decline of Orthodox Christianity: A Study of Kepler, Descartes, and Newton’ (see note l 1), p. 233.Google Scholar
  24. 24.
    Newton, Opticks (see note 9), p. 403. B. J. T. Dobbs, ‘Newton’s Alchemy and his “Active Principle” of Gravitation’ (see note 11), p. 74; see also idem, ‘Stoic and Epicurean Doctrines in Newton’s System of the World’, in Margaret J. Osier (ed.), Atoms,Pneuma, and Tranquility: Epicurean and Stoic Themes in European Thought (Cambridge, 1991), pp. 221–38, especially pp. 232–38.Google Scholar
  25. 25.
    For a full discussion of Newton’s speculations about space as the “sensorium” of God see Edward Grant, Much ado about Nothing: Theories of Space and Vacuum from the Middle Ages to the Scientific Revolution (Cambridge, 1981), pp. 247–54; B. P. Copenhaver, ‘Jewish Theologies of Space in the Scientific Revolution: Henry More, Joseph Raphson, Isaac Newton and their Predecessors’, Annals of Science 37 (1980): 489–548.Google Scholar
  26. 26.
    Newton, Principia (see note 1), p. 545.Google Scholar
  27. 27.
    Newton, Principia (see note 1), p. 544, 546.Google Scholar
  28. 28.
    Newton, Principia (see note 1), p. 546. Westfall, ‘The Rise of science and the Decline of Orthodox Christianity: A Study of Kepler, Descartes, and Newton’ (see note 1 1), p. 233. McMullin also believes that Newton held immanentist views of God’s activity in the world, Newton on Matter and Activity (see note 1), p. 55. For an excellent discussion of how Newton tries to arrive at putative secondary causes rather than rely on God’s direct intervention see David Kubrin, ‘Newton and the Cyclical Cosmos: Providence and the Mechanical Philosophy’, Journal of the History of Ideas 28 (1967), pp. 325–46. For further discussion of Newton’s transcendentalist theology see R. H. Popkin, ‘Newton’s Biblical theology and His Theological Physics’, in Scheurer and Debrock (eds), Newton’s Scientific and Philosophical Legacy (see note II), pp. 81–97; and James E. Force, ‘Newton’s God of Dominion: The Unity of Newton’s Theological, Scientific, and Political Thought’, in J. E. Force and R. H. Popkin, Essays on the Context, Nature, and Influence of Isaac Newton’s Theology (Dordrecht, 1990), pp. 75–102, especially pp. 85–8.Google Scholar
  29. 29.
    On the distinction between potentia absoluta and potentia ordinata see Francis Oakley, Omnipotence, Covenant and Order: An Excursion in the History of Ideas from Ahelard to Leibniz (Ithaca and London, 1984); J. E. McGuire, ‘Boyle’s Conception of Nature’, Journal of the History of Ideas 33 (1972): pp. 523–42; and idem, ‘Force, Active Principles and Newton’s Invisible Realm’ (see note 18).Google Scholar
  30. 30.
    Mediation does not necessarily imply an ongoing continuous process. According to the Oxford English Dictionary “to mediate” can mean: “To be the intermediary or medium concerned in bringing about [a result] or conveying [a gift etc.]Chwr(133) ”.Google Scholar
  31. 31.
    For discussion of Leibniz’s accusation and Newton’s response see Koyré, ‘Attraction an Occult Quality?’, idem, Newtonian Studies (see note 3), pp. 139–48.Google Scholar
  32. 32.
    Papers & Letters, p. 280 (1).Google Scholar
  33. 33.
    Papers & Letters, p. 342 (30).Google Scholar
  34. 34.
    Papers & Letters, p. 341 (29). Bentley, letter to Newton, 18 February 1692/3, in H. W. Turnbull et al (eds), Correspondence of Isaac Newton (see note 17), p. 249.Google Scholar
  35. 35.
    Koyré, ‘Gravity an Essential Property of Matter?’ (see note 3), p. 149, 152. Hall, The Scientific Revolution (see note 2), p. 275.Google Scholar
  36. 36.
    Newton, Opticks (see note 9), p. 339. In saying that English contemporaries would have taken Newton’s voluntarism for granted I do not mean to imply that they all would have accepted it, simply that they would have recognized it for what it was. There were, of course, English thinkers who subscribed to intellectualist forms of theology. They would, presumably, have sympathized more with the thinking of Leibniz. On Leibniz’s intellectualist theology see A. O. Lovejoy, The Great Chain of Being: A Study of the History of an Idea (Cambridge, Mass., 1936), pp. 144–51; Oakley, Omnipotence, Covenant, and Order (see note 29); H. G. Alexander (ed.), The Leihni:Clarke Correspondence (Manchester, 1956); and Steven Shapin, “Of Gods and Kings: Natural Philosophy and Politics in the Leibniz-Clarke Disputes”, Isis 72 (1981): 187–215.Google Scholar
  37. 37.
    McMullin, Newton on Matter and Activity (see note I), pp. 95–101.Google Scholar
  38. 38.
    Koyré, ‘Gravity an Essential Property of Matter?’ (see note 3), p. 149.Google Scholar
  39. 39.
    Newton, Principia mathematica (see note l), Book I, Section XI, p. 164.Google Scholar
  40. 40.
    Cohen, ‘Newton’s Third Law’ (see note 4), p. 592, and footnote 47 on the same page.Google Scholar
  41. 41.
    For further discussion of this point see Peter Dear, ‘Totius in verha Rhetoric and Authority in the Early Royal Society’, Isis 76 (1985): 145–61; and John Henry, ‘Occult Qualities and the Experimental Philosophy: Active Principles in pre-Newtonian Matter Theory’, History of Science 24 (1986): 335–81, especially pp. 358–68.Google Scholar
  42. 42.
    On Cohen’s ‘Newtonian style’ see I.B. Cohen, ‘The Principia, Universal Gravitation, and the “Newtonian Style”, in relation to the Newtonian Revolution in Science: Notes on the Occasion of the 250th Anniversary of Newton’s Death’, in Bechler (ed.), Contemporary Newtonian Research (see note 1), pp. 21–108; and idem, The Newtonian Revolution: With Illustrations of the Transformation of Scientific Ideas (Cambridge, 1980), and ‘Newton’s Third Law and Universal Gravitation’ (see note 4). It was not, incidentally, merely fortuitous that the Royal Society’s carefully forged methodology should prove amenable to Newton’s voluntarism. The leading members of the Society who were responsible for establishing its methods were all theological voluntarists themselves, and they, no less than Newton, were always conscious of the theological import of their work. For a fuller discussion see Henry, ‘Occult Qualities and the Experimental Philosophy’ (see note 41), especially pp. 352–58; and idem, ‘The Scientific Revolution in England’, in R. Porter and M. Teich (eds), The Scientific Revolution in National Context (Cambridge, 1992), pp. 178–210.Google Scholar
  43. 43.
    Newton, Opricks (see note 9), p. cxxiii.Google Scholar
  44. 44.
    Alexander (ed.), Leihniz-Clarke Correspondence (see note 36), Clarke’s Fourth Reply, para. 45, p. 53. Leibniz’s Fifth Paper, paras. 118–19, p. 94, Clarke’s Fifth Reply, para. 118–23, p. 118.Google Scholar
  45. 45.
    Koyré, ‘Gravity an Essential Property of Matter?’ (see note 3), p. 149.Google Scholar
  46. 46.
    Miller, ‘Bentley and Newton’ (see note 15), p. 274, 277.Google Scholar
  47. 47.
    Papers & Letters, pp. 363–4 (11–12, in Part IIi, the Eighth Lecture).Google Scholar
  48. 48.
    Hall, Henry More (see note 2), p. 238.Google Scholar
  49. 49.
    Bentley, Letter to Newton, 18 February, 1693, in H. W. Turnbull et al (eds), The Correspondence of Isaac Newton (see note 18) Vol. 3, p. 249. Miller, “Bentley and Newton” (see note 15), p. 275.Google Scholar
  50. 50.
    Cotes’s letter to Bentley quoted from Koyré, ‘Attraction, Newton and Cotes’, in Newtonian Studies (see note 3), pp. 273–82, p. 281.Google Scholar
  51. 51.
    Koyré, ‘Attraction, Newton and Cotes’, in Newtonian Studies (see note 3), pp. 273–82, p. 281.Google Scholar
  52. 52.
    Cotes, Preface to Newton, Principia mathematica (see note I), p. xxvi. See also Cotes’s letter to Bentley, quoted in Koyré, ‘Attraction, Newton and Cotes’, in Newtonian Studies (see notes 3), pp. 281–2.Google Scholar
  53. 53.
    Newton, Principia mathematica (see note I), pp. 399–400. For a fuller discussion see J.E. McGuire, ‘Atoms and the “Analogy of Nature”: Newton’s Third Rule of Philosophizing’, Studies in the History and Philosophy of Science, 1 (1970) 3–57.Google Scholar
  54. 54.
    Newton, Principia mathematica (see note I), p. 400. This line and what follows, the somewhat laconic closing words of Newton’s comments on Rule 111, have posed severe problems for Newtonian exegetes: “Not that I affirm gravity to be essential to bodies: by their vis insita I mean nothing but their inertia. This is immutable. Their gravity is diminished as they recede from the earth” (p. 400). McMullin (see note I), p. 67. calls this “a perturbed and confusing disclaimer”. For a fuller discussion of the difficulties of interpreting this passage see McMullin, pp. 61–71. In spite of McMulin’s and others’ efforts the passage remains inscrutable. Fortunately the argument presented here does not depend upon the meaning of this passage.Google Scholar
  55. 55.
    See references in note 41 above. The best illustration of how the Royal Society’s method was seen by its adherents as the securest means of arriving at truth is Steven Shapin and Simon Schaffer. Leviathan and the Air-Pump: Hobbes, Boyle and the Experimental Life (Princeton, 1985); but see also Henry, ‘The Scientific Revolution in England’ (see note 42).Google Scholar
  56. 56.
    A. Rupert Hall, in a letter to R. S. Westfall, quoted with permission in Westfall, ‘Newton and Alchemy’, in Brian Vickers (ed.), Occult and Scientific Mentalities in the Renaissance (Cambridge, 1984), pp. 315–335, p. 316.Google Scholar
  57. 57.
    Papers & Letters, p. 341 (29).Google Scholar
  58. 58.
    Newton, Principia (see note 1), p. xxvii.Google Scholar
  59. 59.
    On the “Newtonian style“ see note 42 above. The reference to Newton as the last of the magi is intended, of course, to endorse John Maynard Keynes’s ‘Newton, the Man’, in The Royal Society, Newton Tercentenary Celebrations (Cambridge, 1947), pp. 27–34.Google Scholar
  60. 60.
    For example, Amold Thackray, Atoms and Powers: An Essay on Newtonian Matter-Theory and the Development of Chemistry (Cambridge, Mass., 1970); Robert E. Schofield, Mechanism and Materialism: British Natural Philosophy in an Age of Reason, (Princeton, 1970); Peter M. Heimann and J. E. McGuire, ‘Newtonian Forces and Lockean Powers: Concepts of Matter in Eighteenth-Century Thought’, Historical Studies in the Physical Sciences, 3 (1971): 233–306. For a recent essay which makes the same point see Curtis Wilson, ‘Euler on action-at-a-distance and Fundamental Equations in Continuum Mechanics’, in P. M. Harman and A. E. Shapiro (eds), The Investigation of Difficult Things: Essays on Newton and the History of the Exact Sciences (Cambridge, 1992), pp. 399–420.Google Scholar
  61. 61.
    F. H. van Lunteren, ‘Gravitation and Nineteenth-Century Physical Worldviews’, in P. B. Scheurer and G. Debrock (eds), Newton’s Scientific and Philosophical Legacy (see note 4), pp. 161–73, pp. 166; see also note 38, p. 171, where he provides a sample of references.Google Scholar
  62. 62.
    These are, in case anyone does not recognise them, the closing words of F. Scott Fitzgerald’s, The Great Gatsby (1926) Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 1994

Authors and Affiliations

  • John Henry
    • 1
  1. 1.University of EdinburghUK

Personalised recommendations