First Aid for Introducing Descartes and Introducing Newton

Descartes and Newton are two major seventeenth-century figures in the history of ideas who opened the way for "modernity" (or for what passes as "modernity"). The first was a great philosopher whose speculative theories about science had collapsed within a century (in 1733 Voltaire notes the popularity which they had retained in France rather than in England). The second was a world-class scientist, perhaps the greatest the West has seen, who eschewed philosophical speculation ("hypotheses non fingo"--"I don't touch [or don't fiddle with or concoct hypotheses) and who supported his world-view with painstaking empirical observation.

Introducing Descartes (ID) and Introducing Newton (IN) approach their subjects in comparable ways, dwelling upon individual biography, upon scientific background, ancient and modern, and the ideas and discoveries of D and N.

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ID, 1-12, reviews D's life before the philosopher's famous three dreams and his move in 1628 from Paris to the Netherlands (where he lived incognito with his illegitimate daughter). On 76-81, D's years in Holland are surveyed. D's final years and premature death in Sweden (to which he had moved at the invitation of Queen Christina) are recounted on 156-160. D lived a quiet but philosophically controversial life.

IN, 5, 18-36, reviews N's schooldays and his years as a student at Trinity College, Cambridge. On 80-82, 90-118, the biographical narrative resumes in 1664-5 with the Plague in London (presaged by the heavens?) and proceeds to N's early discoveries, his relationships with the Royal Society and its members (note Hooke), N's alchemical investigations, and his heterodox views of the Bible and Christianity. The origins of N's Principia Mathematica are noted.

On 138-9 the Glorious Revolution is summarized. These are events that culminate in the American Revolution, and IN 159-165 explores some of the intersections between science and politics during the Enlightenment. On 140, N's friendship with John Locke is highlighted. Ensuing pages touch on Newton's sexuality and on what appears to have been a nervous breakdown. On 143-158, the final years of Newton's long life are detailed, including his management of the Royal Mint (143-7), his Presidency of the Royal Society, his disputes with Flamsteed and Leibniz, and his continued labors on a heterodox theology. Note that N played a much greater role than D in the public affairs of his day, although he too was of a retiring disposition. On 174-6, look for observations about the scientist's appearance.

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Swift expressed contempt for Newton but an even greater contempt for Descartes. Swift satirized the Royal Society of London for the Promotion of Natural Knowledge (IN, 100) in the Grand Academy of Lagado where Cartesian dreams of a philosophical language are also mocked (ID, 81). In IN, 159, the importance of Voltaire's appraisal of Newton is underlined. Franklin, like Newton, was deeply involved in problems of currency and the money supply. And like Newton, Franklin explored the laws of the physical world with both precision and imagination (see ID 162 for the utilitarian and the mechanical).

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Both D and N were familiar with and built upon (or demolished) the work of their predecessors, both ancient and modern.

ID, 12-18, 33-38, 62-69, 86 reviews some themes in ancient, medieval, and renaissance science. IN reviews some of the same themes more coherently and intelligibly: see 8-17 (ancient thought, numbers, geometry), 37-70 (physics, cosmology, esp. Galileo [58-68]), 76-78 (neo-platonism) 83-89 (geometry, flux, gravity). In IN, N's objections to D are cogently summarized (71-75, 77, 118, 124, 129-30); the summary of D's ideas in IN is more informative about what D believed than is ID, 19-25.

The major thrusts of Newtonian physics can be found in IN, 83-89, 120-137. Even in comic book form, these can be hard for the non-numerate to grasp, but please struggle with them. Post-Newtonian physics is a complex subject (involving entropy, the sub-molecular, the Big Bang, chaos theory, string theory etc); for a very brief review that culminates with Einstein, see IN 165-171.

ID and IN comprise very different Introductions that reflect the philosopher and the scientist about whom the authors undertook to write. ID is packed with challenging ideas that often seem, simultaneously, half-baked and revolutionary. By contrast, the information in IN is more sequential and coherent--like the world-picture of Newton himself (although students should remember that an action-at-a-distance like gravity represented a conceptual breakthrough that "a mechanical world picture" could not generate).

ID reminds us that Descartes introduced more hypotheses than he could handle and that--despite the philosopher's commitment to mechanistic theories (ID,100-102), to mathematical descriptions (ID, 88-100), and to "clear and distinct ideas" (ID, 25-27)--his philosophy contradicts itself at every twist and turn. Some of D's notions--like his recourse to St. Anselm's "ontological proof" for the existence of God (67-68), his postulation of an "invisible demon" (46-7, 51, 56, 62), or his conviction that animals were machines (101)--immediately strike students as inconsistent with his self-conscious modernity and rationalism.

But some Cartesian speculations continue to provoke debate among philosophers--notably the relationship between mind, brain, and body (111-115)--and other have recently acquired an actuality to which only a dreamer like Descartes could have given voice (for example, virtual reality: ID, 47). Hence ID is full of ideas which may strike students as either self-evident ("cogito ergo sum") or kooky; on the other hand, ID brims with ideas that may yet provide us with keys to e-existence.

ID remains zany--perhaps inevitably so--but its scattershot themes continue to hit new and unexpected targets. If you are frustrated and confused by ID, ask yourself: Do you think that a more coherent and intelligible Introduction could have been written? If so, how?

IN reveals Newton as a visionary rather than as a dreamer. N dedicated himself to the solution of related problems in optics and cosmology, although his forays into alchemy and to biblical study (unknown or little-examined until the twentieth century) shed an unusual (and still controversial) light upon his contributions to our understanding of the physical world. IN is more intelligible and better organized than ID. Does this reflect the different skills of the authors or the coherence of N's science and the incoherence of D's philosophy?

In my opinion, IN is a better book than ID because its presentation of biographical fact, of scientific history, and of Newton's extraordinary achievements is richer and deeper, its attention to detail and nuance more careful. IN does not engage in the same kind of facile generalizations that ID does (but perhaps D invites or necessitates such a sketchy treatment). IN compresses much information into little space and demands careful attention. Bon appetit!