Newton’s Legacy: A Tricentennial Symposium

On April 5, 1687 (Old Style or Julian Calendar) Edmund Halley wrote Isaac Newton that he had received  the  third and final part of his (Newton’s) “divine Treatise.” This was to become Book  Ill of Newton’s Philosophiae Naturalis Prin­cipia Mathematica (Mathematical Princi­ples of Natural Philosophy),  Three months later, on July 5, Halley wrote to Newton that “I  have at length brought your Book to an end. …”

For Halley this was the climax of three draining years, during which he devoted all of his energies to the pains­ taking process of drawing from the of­ ten reluctant Newton the books that were to become the Principia, one of the two or three most important books  in the history of science. (Its competitors, if any, being Copernicus’ De Revolutioni­bus of 1543 and Darwin’s On the Origin of Species in 1859.) The world did not take long to see in the Principia what Halley had: the systematization of the physical world, from a foundation of three axi­oms of motion, a few simple force laws, and a dazzling display of mathematical wizardry. It was so thoroughly convinc­ing to Newton’s contemporaries that it became the model for the eighteenth century, not only in physics or merely in the exact sciences, but in defining the social sciences as well.

The fascinating process by which the Principia came to be is described at length in Richard S. Westfall’s biogra­phy of Newton, Never at Rest. Newton, like other scientific prodigies such as Gauss, Kelvin, and Einstein, wrestled with powerfully original insights in his early twenties. Newton in later years encouraged an image of 1665-6 as his personal annus mirabilis, when he invent­ed the calculus and made other discov­eries in mathematics, and discovered the universal law of gravitation. In the succeeding decade, he made prodigious discoveries in mathematics and optics and became Lucasian Professor of Mathematics at Cambridge. But by 1676, partly because of his altogether private preoccupation with theological studies and his interest in alchemy, Newton had virtually cut himself off from conventional scholarly discourse.

Thus, when Halley posed to Newton, in August 1684, a problem that Westfall calls the great unanswered question confronting natural philosophy, the derivation of Kepler’s empirical laws of planetary motion from first principles, Newton had to say that while he had done the calculation in the past, he could not then reproduce it. Westfall characterizes Newton’s answer as a cha­rade, since the paper in question sur­ vives. In any event Newton’s attention was again engaged, and as Westfall puts it, “the problem had seized Newton and would not let him go.” From August 1684 until the spring of 1686, his life is a virtual blank except for the Principia.

So it is that in 1987 we celebrate the tricentennial of the completion of the Principia, in which Newton showed, or seemed to show, that the entire world, celestial and terrestrial, could be made intelligible within his system. In particu­lar he demonstrated that the properties of the solar system follow from the inverse-square law of gravity. The al­ most inescapable conclusion for later generations was that the universe is ra­tional, predictable, deterministic (though certainly not entirely so to New­ton), and thoroughly mathematical. Others, notably Descartes and Leibniz, played important roles in the scientific revolution, but no figure  dominated  it as did Newton. Indeed, in England a century passed before the authority of Newton faded sufficiently so that fig­ures such as Faraday, Maxwell, and Kel­vin could place their own stamp on the physics of the nineteenth century. No physicist in the 150 years after his death could ignore his work, nor could the humanist; the dramatically contrary re­ actions of Pope and Blake are illustra­tive.

In commemoration of the 300th anni­versary of publication of the Principia, a symposium, “Newton’s Legacy,” is being held in New Orleans on November 12-14, 1987. The symposium, which is sponsored by the Louisiana Endowment for the Humanities, a state program of the National Endowment of the Hu­manities, and by Tulane University, will focus on the “centennial” years 1687, 1787, 1887, and 1987 as a means of exploring the impact of Newton’s thought on each of the three centuries that have elapsed since the publication of the Principia.

A little reflection will reveal the logic of this choice. Whether one focuses on the work of the renowned French math­ematical physicists Laplace and La­grange, or the great social and cultural movements of the period, the Enlight­enment and the French Revolution, the late eighteenth century is representative of the triumph of the Newtonian meth­od, just as the earliest discoveries in electricity and magnetism by Franklin, Volta, Coulomb, Ampere, and others began to add an entirely new dimension to classical physics.

Similarly, the end of the nineteenth century represents the final culmination of classical physics with the develop­ment of thermodynamics, kinetic the­ory, and the electromagnetic theory of Faraday and Maxwell.

And yet at the same time, the un­solved problems of classical physics were beginning to pave the way toward the two great revolutions of the twentieth century, the quantum theory and the theory of relativity. It is also the era of electrification, the second industrial rev­olution, the period out of which erupted the modern world in the arts as well as in the sciences.

Finally, in 1987 we live in a world that can be thought of as post-Newtonian in a variety of ways, and one of the issues to be explored in the symposium is the extent to which the late twentieth centu­ry is still Newtonian. It is also a world in which the successes of physics, Newtoni­an and modern, have increasingly been called into question. In this sense also, one must examine Newton’s legacy.

Among the plenary speakers at the Tulane symposium are: I. Bernard Co­hen, whose study with Alexandre Koyre is the definitive work on the Principia itself, and whose work includes studies of Franklin and Newton, the Newtonian revolution, and more generally the process of scientific transformation; Richard S. Westfall, whose influential biography Never at Rest we have already quoted and who is an authority on, among other things, Newton’s theological writings; Thomas L. Hankins, whose work on science and the Enlightenment includes a volume on D’Alembert; L. Pearce Williams, who has written exten­sively on nineteenth-century science, field theory, and in particular on Fara­day and Ampere; Joseph Agassi, whose broad writings in the history, philoso­phy, and sociology of science include Faraday as a Natural Philosopher; Max Jammer, a leading philosopher and his­torian of the quantum theory; and Hen­ry P. Stapp, a physicist whose interests and writings have ranged from particle physics to the foundations of the quan­tum theory.

The goal of the Tulane symposium is that from the plenary lectures, contrib­uted papers, and formal and informal discussions should emerge a deeper understanding of the Principia and its in­ fluence, and a fuller picture of Newton the man, and that these should be com­municated to a broad audience, espe­cially within the region. To this end, the symposium is free and open to the gen­eral public.

Additional information is available from the Organizing Committee, New Orleans Principia Symposium, Depart­ment of Physics, Tulane University, New Orleans, LA 70118. In addition to the authors, members of the committee are Henry Folse, Department of Philosophy, Loyola University of New Or­ leans; Norton Nelkin, Department of Philosophy, University of New Orleans; and Richard Teichgraeber, Department of History, Tulane.