The Philosophy of Nature (review)

624 JOURNAL OF THE HISTORY OF PHILOSOPHY 27:4 OCTOBER 198 9 term 'notion' " was due to the fact that most of his contemporaries "took notions to be intentional objects" (191). Flage's conclusion is "that notions are to be construed as intentional acts" (2o8). This is at best awkward. For it must be entertaining or employing a notion, rather than that notion itself, which is any sort of act, intentional or other. Flage's final chapter, as its title suggests, consists in "Conclusions and Historical Speculations." He believes, for reasons given, that Berkeley had developed his doctrine of notions by the time he first published the Principles. Flage would strengthen his case were he prepared to add what he conjectures was Berkeley's reason for not showing his hand sooner. ANTONY FLEW Reading, England Ivor Leclerc. The PhilosophyofNature. Studies in Philosophy and the History of Philosophy (gen. ed., Jude P. Dougherty), Vol. 14. Washington, D. C.: The Catholic University of America Press, 1986. Pp. xii + 22o. $3 a.95. One is immediately sympathetic to the spirit and aims of Leclerc's contribution to this valuable series. He has provided a welcome apologia for the subject of his study, arguing the necessity of reviving the philosophicalstudy of nature, to complement and enrich the purely "scientific" investigations that these days exhaust the range of professional interests of practitioners of the physical sciences. If successful, this program would restore something that has been missing since the days of Kant, in whose unknowable and inaccessible Ding an sich Leclerc finds the watershed between an age of authentic philosophy of nature and an age in which philosophy has become "essentially a philosophy of mind or spirit." Yet, he argues, "it is precisely the physical Ding an sich which is required to be the primary object of the philosophy of nature" (12). Leclerc presents his case via a study of "the philosophy of nature" principally in the seventeenth and eighteenth centuries. He gives three reasons for this approach (13). First seventeenth-century philosophers of nature elaborated their ideas against the background of Aristotelian doctrines, so "they gained from their detailed study of Aristotle a singularly good grasp of the fundamental issues involved in the philosophy of nature" (13). Second, our assessment of the state of affairs today should depend on a serious understanding of science and philosophy in the past. Third, this historical approach helps us distinguish between the philosophical and scientific issues and clarify the relations between them. No need to explain to faithful JHP readers that these last two points will have most contemporary philosophers of science scratching their heads. Accordingly, Part 2 (Historical) provides useful and skillfully managed expositions, and in some instances reinterpretations (Kant on space), of concepts of nature, doctrines of substance, matter and mind, motion and space, as found in the writings of Peripatetics , seventeenth-century atomists, Galileo, Descartes, Gassendi, Leibniz, Locke, Newton and Kant. Building on this historical background, in Part 3 (Issues) Lederc develops critical analyses of seven fundamentally important philosophical problem areas created BOOK REVIEWS 625 by twentieth-century science: the physical existent; the physical existent as a compound actuality; relations; physical existence, matter, and activity; compounds, body, change; motion, action, and physical being; Platonism, Aristotelianism, and modern science. In his treatment of the last of these issues, which takes up the concluding chapter, Leclerc argues that the epistemological subjectivism ("the essential Neoplatonic position ," 2o5) spawned by Kant and taken to its metaphysical culmination by Hegel and the positivists, should now be displaced by an epistemological realism in tune with the revolutionary findings of contemporary science. The philosophy of nature, he writes (2o7), "entails that nature or the physical be in itself the object of philosophical inquiry, and this it is unable to be on the Neoplatonic subjectivistic basis." To effect this philosophical transformation, we might take our cue from Whitehead, who saw "more clearly than most that this change entailed the complete rejection of the metaphysics upon which modern science had been based since the seventeenth century, that a new metaphysics is accordingly now necessary as a basis for science, and [who] has gone further than any other thinker in elaborating such a metaphysics" (2o7...