¹ The present author has dealt with some aspects of the problem in earlier publications: (a) ‘Science and theology in the Middle Ages’, Free Univ. Qu. (1954), 3, pp. 77–163 (in particular, pp. 77–82, 88–97, 103–118, 131–137)Google Scholar; (b) Religion and the Rise of Modern Science, Edinburgh and London, 1972 ff (pp. 9–13, 29–41, 61–66, 88–94)Google Scholar; (c) Das Verhältnis von Physik und Mechanik in historischer Hinsicht, Wiesbaden, 1963Google Scholar (reprinted in: Hooykaas, R., Selected Studies in History of Science, Coimbra, 1983, pp. 167–199)Google Scholar; (d) ‘Von der “physica” zur Physik’, in: Humanismus und Naturforschung, Beitr. Humanismusforschung VI, Boppard, 1980, pp. 9–38Google Scholar (reprinted in: Selected Studies, op. cit., pp. 599–634)Google Scholar; (e) Science in Manueline Style, the Historical Context of D. Joāo de Castro's Works, Coimbra, 1980Google Scholar [pre-print of: Obras Completas de D.Joāo de Castro, (ed. de Albuquerque, A. Cortesāo e L.), vol. IV, Coimbra, 1982, pp. 231–426 (in particular pp. 3–12, 92–98, 146–152, 163–167)].Google Scholar

² On this topic, see: (a) Dijksterhuis, E.J., Doel en Methode van de Ceschiedenis der Exacte Wetenschappen, Inaugural address, Utrecht, 1952, pp. 13–20Google Scholar; (b) Hooykaas, R., L'histoire des Sciences, ses Pmblèmes, sa Méthode, son But, Coimbra, 1962Google Scholar (also in: Rev. Fac. de Ciências Coimbra, (1963), 32, pp. 5–35Google Scholar); (c) Frangsmyr, T., ‘Science or history, G. Sarton and the positivist tradition in the history of science’, Lychnos, (1973–1974), pp. 104–144Google Scholar; (d) Krafft, F., ‘Die Naturwissenschaften und ihre Geschichte, Sudhoff's Arch. (1976), 60, pp. 317–337Google Scholar; (e) Hooykaas, R., ‘Pitfalls in the historiography of geological science’, Nature et Histoire, (1982), 19–20, pp. 21–33Google Scholar; (f) Hooykaas, R., ‘Wissenschaftsgeschichte, eine Brücke zwischen Naturund Geisteswissenschaften’, Berichtez. Wissensch. Geschichte, (1982), 5, pp. 162–170.Google Scholar

³ Duhem, P., Le Système du Monde, VI, 2nd edn., Paris, 1954, p. 66.Google Scholar

⁴ Thorndike, L., A History of Magic and Experimental Science, III, New York, 1934, p. 470.Google Scholar

⁵ Buridanus, J., De Coel et Mundo, lib. I, qu. 16Google Scholar, Oresme, N., Le livre du Ciel et du Monde (c. 1370), I. II, 95c (ed. Menut, A.D. and Denomy, A.J.), Madison, 1965, p. 374.Google Scholar

⁶ Duhem, P., Etudes sur Leonardde Vinci, III, p. XIGoogle Scholar; II, p. 411. Cf. Gilson, E., La Philosophie au Moyen Age, 3rd edn., Paris, 1947, pp. 460, 487.Google Scholar

⁷ de Castro, D. Joāo, Tratado da Esfera (c. 1538), Obras I, p. 58.Google Scholar

⁸ Ramus, P., ‘Scipionis Somnium’ (1546), in: Petri Rami Praelectiones in Ciceronis Orationes octo consiliares, Basileae, 1580, p. 53.Google Scholar

⁹ Cf. (a) Hooykaas, R., Het Begrip Element in zijn historisch-wijsgeerige ontwikkeling, thesis: Utrecht, 1933, pp. 148–154Google Scholar; (b) The discrimination between natural and artificial substances and the development of corpuscular theory’, Arch. Intern. Hist. Sci. (1948), 4, pp. 840–858Google Scholar; (c) ‘The experimental origin of chemical atomic and molecular theory before Boyle’, Chymia, (1949), 2, pp. 65–80Google Scholar (reprinted in: Selected Studies, op. cit. (1), pp. 285–308).Google Scholar

¹⁰ Cf. Hooykaas, R., Science in Manueline Style, op. cit. (1), pp. 50–61.Google Scholar

¹¹ With Galileo the relation between reason and observation was rather ambiguous. He was no empiricist in the Baconian sense—perhaps even less so than Kepler (he never abandoned the circularity of the celestial motions). He seems to have put greater trust in the reliability of human reason than in that of the human senses. He praised Aristarchus and Copernicus for having maintained that Venus revolves around the sun, although its apparent size seemed to remain the same: with them, according to Galileo, reason so much overpowered the senses that they made it ‘the mistress of what they believed’ and made the choice that has turned out to be the right one, as is now shown by the telescopic observations of the changing size and the phases of that planet. ‘Nor can I sufficiently admire the eminence of these mens’ wits that… have been able to prefer that which their reason dictated to them, to that which sensible experiments represented most manifestly on the contrary’ (Dialogue III). Nevertheless, he was immensely proud of ‘the perfection of our sight’ by the invention of the telescope, for he, too, finally recognized that Experience is ‘the true Mistress of Astronomy’ (ibid.).

In many cases, better methods of observation confirmed his trust in Reason, but in his account of ebb and flood [1616; Dialogue IV (1633)Google Scholar] it led him astray. He selected experimental data that seemed to favour his mechanistic theory of the tides, according to which the basic phenomenon recurred in periods of twelve (instead of six hours). He ignored the generally known relation between the moon and the tides. According to his erroneous theory, ebb and flood could not occur if the earth were immovable. Consequently, he considered his theory of the tides one of the three main proofs of the Copernican system (the other two being the revolution of the sun around its axis and the retrogradations of the planets).

¹² Cf. Hooykaas, R., ‘De Baconiaanse Traditie in de Naruurwetenschap’, Algemeen Ned. Tijdschr. v. Wijsbegeerte, (1961), 53, pp. 181–201.Google Scholar

¹³ Pemberton, H., A View of Sir Isaac Newton's Philosophy, London, 1728, pp. 5 ff.Google Scholar

¹⁴ Bacon, F., ‘Historia naturalis et experimentalis’, in: The Works of Francis Bacon, (eds Spedding, J., Ellis, R.L. and Heath, D.D.), London, 1857–1874, vol. II, p. 14.Google Scholar

¹⁵ Farrington, B., The Philosophy of Francis Bacon, Liverpool, 1964, p. 21.Google Scholar

¹⁶ Bacon, , Novum Organum I, aph. 68Google Scholar; Works I, p. 179.Google Scholar

¹⁷ Bacon, , Nov. Org. I, aph. 95Google Scholar; Works I, p. 201.Google Scholar

¹⁸ Bacon, , Historia Nat. et Exp.; Works II, p. 15.Google Scholar

¹⁹ Bacon, , Nov. Org. I, aph. 96Google Scholar; Works I, p. 201.Google Scholar

²⁰ Bacon, , Nov. Org. I, aph. 84Google Scholar; Works I, p. 191.Google Scholar

²¹ Bacon, , De Augmentis, lib. II, c. 10Google Scholar; Works I, p. 514Google Scholar. Also: Nov Org. I, aph. 93; Works I, p. 200.Google Scholar

²² Bacon, , Nov. Org. I, aph. 95Google Scholar; Works I, p. 200.Google Scholar

²³ See fn. 11, on Galileo.

²⁴ The late Professor Dijksterhuis, E.J. (De Mechanisering van het Wereldbeeld, Amsterdam, 1950, pp. 319–332)Google Scholar allowed the period of the building up of the modern mechanistic world picture to run sharply from 1543 (Copernicus) to 1687 (Newton) (op. cit., p. 317). Further on, however, he said of Copernicus's work that ‘apart from the use of the trigonometrical modes of computation, there is nothing in it that could not have been written in the 2nd century A.D. by a successor of Ptolemy’ (op. cit., p. 319). Dijksterhuis's outline of Copernicus's theory is not essentially different from that we have given now. Moreover, he was an outspoken advocate of what he termed the ‘phenomenological method’ in historiography of science (cf. his Doel en Methode mentioned in fn. 2). He, too, was of the opinion that modern astronomy really began with Kepler's New Astronomy: ‘here we are confronted with one of the most important events in the history of thinking, perhaps even the real turning-point of the innovation that forms the theme of this book’ (op. cit., p. 338). It hardly needs mentioning that Dijksterhuis found neither new important facts nor traces of a mechanistic world picture in the works of the astronomer, whom he nevertheless highly admired. (The title of Professor Cohen, H.F.'s recent inaugural address at the Technical University of Twente, On the Character and Causes of the 17th Century Scientific Revolution (Amsterdam, 1983)Google Scholar, implies that in his opinion the ‘revolution’ did not start with Copernicus. His lecture develops a plan for a thorough investigation of the present topic.)

²⁵ In particular, historians of science who have been educated as mathematicians, astronomers or physicists will have an open eye to the fact that physical (or mechanical) processes form the basis of all change in nature, and thus physics (or mechanics) is the most fundamental discipline. But not all sciences of nature have as yet been mathematized (or ‘mechanicized’), although, nevertheless, they may claim to be ‘scientific’: empirical knowledge and classification are also ‘science’. Many scientific discoveries, e.g., in chemistry, have been made without mathematization or mechanization (see: Het Begrip Element—The Concept of Element, pp. 145–159Google Scholar); this is even more so in botany and zoology. On the other hand, all sciences of nature are based on ‘natural history’: we start from facts and we end with facts which we classify, either in a mathematical or in a non-mathematical way.

²⁶ Aristotle made a distinction between the cause of a ‘motion’ (the transition from potentiality to actuality) and the incidental so-called ‘cause’ which is nothing but the removal of an obstacle hindering the true cause of nature (‘… if anyone removes the obstacle he may be said in one sense—but in another not—to cause the movement; e.g. if he removes a column from beneath the weight it was supporting … for he accidentally determines the moment at which the potential motion becomes actual’. Physica VIII, 4Google Scholar; 255b, 20ff).

The physicist Robert Mayer, in an article ‘Ueber Auslösung’ (1876)Google Scholar, spoke of ‘loosening’ (untying) or ‘releasing’ causes, in which there is no proportionality between cause and effect: a very small ‘Anstoss’ will, in general, have a much greater effect, e.g. when a light pressure of the finger ‘causes’ the enormous effect of a gun. He distinguished such release-causes from those about which he posited the thesis that ‘the cause is equal to the effect’, which he applied in his law of conservation of energy (Mayer, R., Die Mechanik der Wärme (ed. Weyrauch, J.J.), Stuttgart, 1893, pp. 440–447Google Scholar). Such ‘amplifying’ processes are of course the basis of modern information technology.