1 Some modern authors have made a strong case for the existence of the aether. See, for instance, Samuel, V. and Dingle, H. A Threefold Cord: Philosophy, Science, Religion (London, 1961), Appendix 1, pp. 265–269Google Scholar, where Dingle quotes famous modern scientists such as Einstein, Dirac, and Whittaker in support of the aether. According to Dingle, radio and television stations do not go “on the air” but “on the aether.“

2 See Freeman, K. Ancilla to the Pre-Socratic Philosophers (Oxford, England, 1962), pp. 41–44Google Scholar. See also Peters, F. E. Greek Philosophical Terms (New York University Press, 1967), p. 101: Kenon.Google Scholar

3 See S. T., I, 33, 4, ad 3.

4 See S. T., I, 16, 3, ad 2.

5 See Timaeus, 57e-58c.

6 See Physics, VIII, 10, 266b29-267a2.

7 See De Caelo, Ill, 2, 301b26-31; Physics, VIII, 10, 267a3-13.

8 See Physics, IV, 8, 215a19-22. This has been called Aristotle's theory of inertia. Cf. McWilliams, J. A. Physics and Philosophy (Washington, D.C., 1945), p. 17Google Scholar: “The doctrine of all these four is identical, and the very wording is so nearly so, that not only St. Thomas but Descartes and Newton would appear to have copied their statements directly from Aristotle.“

9 See Physics, IV, 8, 215b19-216a19.

10 See De Caelo, IV, 6, 313b18-23. T/SOCR/W=S/TOCW/R=VOCW/R. Although Galileo seems to have interpreted the Aristotelians as thinking in terms of only falling bodies, Aquinas did not do so. See his Commentary on Aristotle's Physics (trans. Blackwell, R. J. Spath, R. J. and Thirlkel, W. E. [Yale University Press, 1963] ), IV, 12, 529, p. 235Google Scholar. Neither was Aristotle thinking only in terms of terminal velocities. See Drabkin, I. E. “Notes on the Laws of Motion in Aristotle,“ American journal of Philology, LIX (1938), 78Google Scholar. On the dates of Aquinas's works used in this paper see Bourke, V. J. Introduction to the Works of St. Thomas Aquinas (New York, 1948).Google Scholar

11 Summa Theologiae, 1, 3, 5.

12 See Grant, E. “Medieval and Seventeenth-Century Conceptions of an Infinite Void Space Beyond the Cosmos,” Isis, LX (1969), 41.Google Scholar

13 See the translation of his Commentary already cited: IV, 12, 534, p. 238. Some think that Aquinas was led to his own view by several predecessors such as Philoponus, Avempace, and Avicenna. See Moody, E. A. “Avempace and Galileo,“ journal of the History of Ideas, XII (April 1951), Part I, 163–193CrossRefGoogle Scholar; (June 1951), Part II, 375-422. Others can find little or no continuity. Cf. Sambursky, S. The Physical World of Later Antiquity (New York, 1962), pp. 174–175Google Scholar: “One is tempted to speculate on how the course of the history of ideas would have been changed had the doctrine of Philoponus been accepted by the Church instead of the Aristotelian conceptions. Had for instance Thomas Aquinas chosen Philoponus' ideas and incorporated them in the scientific foundations of Christian philosophy, the birth pangs of the Copernican and Galilean revolution would perhaps have been less severe and scientific progress possibly accelerated.“

14 See Commentary, IV, 12,534-538, pp. 238–241. Aquinas does not put to Aristotle the question about how the same medium which causes projectile motion can also be responsible for stopping it.

15 Ibid., 539, pp. 241–242.

16 See ibid., 536, pp. 239–240. See also De Potentia Dei, 3, 11, ad 5. The question of whether or not Aquinas was consciously substituting the formula VOC(W-R) for Aristotle's VOCW/R is still open. Moody seems to think he did while Sambursky seems to think otherwise. Further, there seems to be no connection at all between Aquinas's treatment of the formulation and the later treatment accorded it by Thomas Bradwardine (1290-1349) who introduced the equivalent of logarithms into the formula in order to have V equal zero when W equalled R. See his Tractatus de Proportionibus (trans. and ed. Crosby, H. L. [University of Wisconsin Press, 1955]Google Scholar). Also, as M. Clagett, referring to Thomas's de caelo et mundo expositio, points out, the impressed motion cannot be a substantial form because this would change the very nature of the thing moved. See his The Science of Mechanics in the Middle Ages (University of Wisconsin Press, 1961 ), pp. 516–517. Yet Thomistic impetus theory should not be overlooked as some have done. Cf. Grant, E. Physical Science in the Middle Ages (New York, 1971), p. 50.Google Scholar

17 S.T., 1, 46, 1, ad 4.

18 S. T., Supp., 84, 3, ad 2. As is clear from other passages, the celestial bodies are composed of a fifth essence or element but are not in such an element. See S. T., I, 10,5;70,3.

19 Force in Newton's Physics (London, 1971 ), p. 409, note 115.

20 Mathematical Principles of Natural Philosophy (Cajori, ed.; Berkeley, 1946), Book III, L.IV, cor. III, p.497Google Scholar. See Koyré, A. From the Closed World to the Infinite Universe (New York, 1957), Chap. VII.Google Scholar

21 Cf. Koyré, op. cit., p. 209Google Scholar: In his Opticks, “Newton does not tell us outright-any more than he does in the Principia-what these various ‘Powers’ [by which bodies act across space] are. just as in the Principia, he leaves that question open, though, as we know, he holds them to be non-mechanical, immaterial and even ‘spiritual' energy extraneous to matter.”

22 Cf. ibid., p. 301, note 3: “I am, thus, morally certain that Clarke communicated to Newton both Leibniz's letters and his own replies to them …. As a matter of fact, the Princess of Wales informed Leibniz … that he was right in his supposition that these letters were not written without the advice of Newton. Strange as it may seem, the importance of Clarke's papers as representing literally the metaphysical views of Newton has never been recognized, with the result that their study was completely neglected by the historians both of Newton and of Leibniz.” See also his Newtonian Studies (Harvard University Press, 1965), Appendix D, pp. 164–169. The Princess had been a friend to Leibniz in her younger days and was now living in England as the wife of the future George II.

23 The Leibniz-Clarke Correspondence, ed. Alexander, H. G. (Manchester University Press, 1956), p. 120Google Scholar. Clarke's own view is that infinite space is an attribute or property of God just as eternal duration is a property of God. Newton would prefer to call it a necessary effect of God. Leibniz, however, using the Scholastic terminology of the time, could see no difference. To say that the ability to laugh, for instance, is a property of man is the same as saying that it is a necessary effect of man's rational nature. (See ibid., p. xxix.)

24 Professor Alexander would seem to be mistaken when he states that in Einstein's General Theory of Relativity, in contradistinction to Newton's space and time, “space-time is given some sort of reality. For part, if not all, of what is meant by calling a thing real is that one can ascribe properties to it.” (Ibid., p. lv.) Cf. the remarks of Sir A. Eddington, one of Einstein's chief disciples: “We must rid our minds of the idea that the word space in science has anything to do with void …. In any case the physicist does not conceive of space as void. Where it is empty of all else there is still the aether. Those who for some reason dislike the word aether, scatter mathematical symbols freely through the vacuum, and I presume that they must conceive some kind of characteristic background for these symbols. I do not think any one proposes to build even so relative and elusive a thing as force out of entire nothingness.” The Nature of the Physical World (University of Michigan Press, 1958), p. 137. Newton's disciples did in fact say the same sort of thing.

25 See McWilliams, J. A. op. cit., p. 18.Google Scholar

26 Commentary, Ill, 4, 301, p. 143.

27 See ibid., IV, 9, 497, p. 224; 10, 509, pp. 227–228. It should also be remembered that for Aquinas to be did not mean to have properties. Properties also are and consequently to view being in such terms would be quite circular.

28 S. T., 1, 70, 3, ad 3.

29 See On Spiritual Creatures, 6, ad 12; De Potentia Dei, 3, 11, ad 14; 6, 6, ad 10.

30 Modern scientists, of course, recognize the great influences of the sun and moon upon the earth. Except for gravity, space deformation due to matter, and one or two other influences, however, most of the influences of stars and planets have been relegated to astrology. The part about angels propelling the luminous orbs has been called worse things.

31 See S.T., I, 32, 1, ad 2.