Kant's Newtonian Revolution in Philosophy (review)

622 JOURNAL OF THE HISTORY OF PHILOSOPHY 28:4 OCTOBER 199o science--even if an alternative one--and the cogency of his explanations must be fully examined in the context of his times. The central portion of the book is devoted to "dissecting" Newton's first public account of his theory of color in his 1679 letter to the Royal Society. Sepper's aim is to show its hidden assumptions, inconsistencies, incomplete descriptions of the phenomena , and especially its failure to prove the unequal refrangibility of rays of light as a "fact." To appreciate the boldness of this strategy one must recognize that virtually all scientists from Newton's day onwards have accepted that part of Newton's theory that treats unequal refrangibility; this then serves as the foundation for the second part of his theory that treats the nature of white light and color, and it is this part that has always encountered some opposition. It would take a more sophisticated philosophy of science and historical analysis than Sepper brings to bear to explain why scientists did and do accept an imperfectly formulated theory. The decision to subject the 1672 paper to an analysis "in the spirit of Goethe" (1o4) is methodologically unjustifiable, since whatever real and imagined flaws Sepper finds are irrelevant. What is at issue is Goethe's assessment of the flaws in Newton's theory. Goethe himself in Zur Farbenlehre dissected the Opticks and not the 1679 paper, even though at one time, as Sepper shows, he planned and began the latter task. Sepper'sjustification of his approach, namely, that Newton's 1672 version of the theory is not essentially different from that of the Opticks, is simply not true. The 1672 paper contains the briefest sketch of his discoveries, a small fraction of the size of his earlier Optical Lectures (167o-7a) and later Opticks 07o4). At Sepper's detailed level of analysis both the theory and methods of proof changed significantly during the course of thirty years. Moreover, by choosing to criticize Newton rather than understand him, Sepper finds flaws in Newton's arguments that even Goethe did not imagine. He spends several pages (137-39) arguing that Hooke should not have conceded that Newton's crossed-prism experiment refutes his "diffusion" theory of color. In fact, both Newton's demonstration and Hooke'sconcession were valid, for the experiment does not concern Hooke's oblique pulses, as Sepper seems to think, but Hooke's "split and diffused" rays. Sepper tends to treat Newton as a contemporary of Goethe rather than as a real historical figure of the late seventeenth century who was fighting his own battle to reform science. The intervening century is largely ignored and the book fails to show how far out of the scientific mainstream Goethe was from the beginning of his researches, even before the polemics. ALAN E. SH^PIRO University of Minnesota Robert Hahn. Kant's Newtonian Revolution in Philosophy. The Journal of the History of Philosophy Monograph Series. Carbondale: Southern Illinois University Press, 1988. Pp. x + 143. Paper, NP. In the preface to the second edition of the Critique ofPure Reason, Kant summarizes his strategy by way of a brief parallel with what he calls "the first thoughts of Copernicus." Perhaps because this passage occurs in the context of an account of scientific revolu- nook REVI~WS 623 tion, perhaps because the expression "Copernican Revolution" already had some currency by the end of the eighteenth century, perhaps because Kant thought of his own approach to the solution of the main problems of metaphysics as revolutionary, commentators (beginning, perhaps, with Charles de Villers in a799) were quick to broadcast the notion that Kant had, or thought he had, effected a "Copernican Revolution" in philosophy, although (as might be expected) disagreeing among themselves as to just what the "revolution" involved and how far the supposed parallel with Copernicus might be pushed. In our own time, the phrase "Kant's Copernican Revolution" has become well nigh standard (it is, in fact, the title of another recent book on Kant). As have several others before him--most vigorously I. B. Cohen in Revolution in Science(1985)--Robert Hahn protests that Kant never...