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Superiorum Permiffu, & Privilegio.
Galileo Galilei, Sidereus mincius (1610): title page. This little book marks a turning-point in Galileo's life. Here he published his first telescopic discoveries, notably of the mountainous surface of the Moon and the satellites of Jupiter, which he named the Medicean stars after the Grand Duke of Tuscany. Here also he showed a serious commitment to the Gopernican system.
NATURE IN MEDIEVAL
AND MODERN THOUGHT
A.C. CROMBIE
THE HAMBLEDON PRESS
102 Gloucester Avenue, London NW1 8HX (UK) PO Box 102, Rio Grande, Ohio 45674 (USA) ISBN 1 85285 067 1
© Alistair Cameron Crombie 1996
A description of this book is available from the British Library and from the Library of Congress
Printed on acid-free paper and bound in Great Britain by Cambridge University Press
Acknowledgements vii Illustrations ix Preface xi Further Bibliography of A.C. Crombie xiii
1 Designed in the Mind: Western visions of Science, Nature and
Humankind 1 2 The Western Experience of Scientific Objectivity 13 3 Historical Perceptions of Medieval Science 31 4 Robert Grosseteste (c. 1168-1253) 39 5 Roger Bacon (c. 1219-1292) [with J.D. North] 51 6 Infinite Power and the Laws of Nature: A Medieval Speculation 67 7 Experimental Science and the Rational Artist in Early Modern
Europe 89 8 Mathematics and Platonism in the Sixteenth-Century Italian
Universities and in Jesuit Educational Policy 115 9 Sources of Galileo Galilei's Early Natural Philosophy 149 10 The Jesuits and Galileo's Ideas of Science and of Nature
[with A. Carugo] 165 11 Galileo and the Art of Rhetoric [with A. Carugo] 231 12 Galileo Galilei: A Philosophical Symbol 257 13 Alexandre Koyré and Great Britain: Galileo and Mersenne 263 14 Marin Mersenne and the Origins of Language 275 15 Le Corps à la Renaissance: Theories of Perceiver and Perceived
in Hearing 291 16 Expectation, Modelling and Assent in the History of Optics: i,
Alhazen and the Medieval Tradition; ii, Kepler and Descartes 301 17 Contingent Expectation and Uncertain Choice: Historical Contexts
of Arguments from Probabilities 357 18 P.-L. Moreau de Maupertuis, F.R.S. (1698-1759): Précurseur du
Transformisme 407 19 The Public and Private Faces of Charles Darwin 429 20 The Language of Science 439
21 Some Historical Questions about Disease 443 22 Historians and the Scientific Revolution 451 23 The Origins of Western Science 465 Appendix to Chapter 10: 479
(a) Sources and Dates of Galileos Writings [with A. Carugo] (b) Pietro Redondi, Galileo eretico (Torino, 1983) [with A. Carugo] (c) Mario Biagioli, Galileo, Courtier (Chicago, 1993)
Corrections to Science, Optics and Music in Medieval and Early
Modern Thought (1990) 495 Index 497
The articles reprinted here first appeared in the following places and are reprinted by kind permission of the original publishers.
1 History of Science, xxvi (1988), pp. 1-12.
2 Proceedings of the 3rd International Humanistic Symposium 1975: The Case of Objectivity (Athenai: Hellenistic Society for Humanistic Studies, 1977), pp. 428-55.
3 In Italian in Federico II e le Scienze: Proceedings of the International Seminar on Frederick II and the Mediterranean World (1990), a cura di A. Paravicini Bagliani (Palermo: Sellerio, 1995).
4 Dictionary of Scientific Biography, ed. C.C. Gillispie, v (New York: Charles Scriber's Sons, 1972), pp. 548-54.
5 Ibid., i (1970), pp. 377-85.
6 L'infinito nella scienza, a cura di G. Toraldo di Francia (Roma: Enciclopedia Italiana, 1987), pp. 223-43.
7 Daedalus, cxv (1986), pp. 49-74.
8 Prismata: Naturwissenschaftsgeschichtliche Studien: Festchrift fur Willy Hartner, hrsg. Y. Maeyama aund W.G. Salzer (Wiesbaden: Franz Steiner Verlag GmbH, 1977), pp. 63-94.
9 Reason, Experiment and Mysticism in the Scientific Revolution, ed. M.L. Righini Bonelli and W.R. Shea (New York: Science History Publications, 1975), pp. 157-75.
10 Annali dell' Istituto e Museo di Storia della Scienza di Firenze, viii.2 (1983), pp. 1-68.
11 Nouvelles de la république des lettres (1988) ii, pp. 7-31.
12 Actes du VIIle Congrés International d'Histoire des Sciences (Florence, 1956), pp. 1089-95.
13 The Renaissance of a History: Proceedings of the International Conference Alexandre Koyré, Paris, 1986, ed. P Redondi: History and Technology, iv (London, 1987), pp. 81-92.
14 In French in Nature, histoire, société: Essais en hommage à Jacques Roger, éd. C. Blanckaert, J.-L. Fischer, R. Rey (Paris: Editions Klincksieck, 1995); Appendix: The Times Literary Supplement, 2 October 1992, p. 23. 15 Le Corps à la Renaissance: Actes du XXXe Colloque de Tours 1987, sous
la direction de J. Céard, M.M. Fontaine, J.-C. Margolin (Paris: Aux Amateurs de Livres, 1990), pp. 379-87.
16 Studies in History and Philosophy of Science, xxi (1990), pp. 605-32, xxii (1991), pp. 89-115.
17 The Rational Arts of Living, ed. A.C. Crombie and N.G. Siraisi, Smith College Studies in History, vol. 50 (Northampton, Mass., 1987), pp. 53-101; first version published in French in Médecine et Probabilités: Actes de la Journée d'Etudes du 15 December 1979, éd. A. Fagot (Paris: I'Univer-sité Paris-Val de Marne, 1982).
18 Revue de synthèse, lxxviii (1957), pp. 35-56.
19 First published as 'Darwin's Scientific Method' in Actes du IXe Congrès International d'Histoire des Sciences, Barcelona-Madrid 1959 (Barcelona/ Paris, 1960), pp. 354-62; reprinted in The Listener (London: B.B.C., November 1959).
20 Presented at the Forum de la communication scientifique et technique: Quelles langues pour la science?, organise a l'initiative du Ministère de la Francophonie; published in French in Alliage: Culture Science -Technique, no. 4 (Eté, 1990), pp. 39-42.
21 Sida: Epidémies et sociétés, 20 et 21 juin 1987, éd. C. Mérieux (Lyon, 1987), pp. 115-21.
22 Physis, xi (1969), pp. 167-80. 23 Metascience, n.s.ii (1993), pp. 1-16.
Galileo Galilei, Sidereus nuncius (1610): title page ii Figure illustrating Roger Bacon's fifth rule 56 Galileo Galilei, from // Saggiatore (1623) : frontispiece 88 The beginning of Galileo's autograph Disputationes 152 Autograph page of Galileo's Tractatio de Caelo 154 Watermark showing a backward-looking lamb 157 Diagram of the Copernican system, with the Sun in the centre,
from Galileo's Dialogo (1632) 164 Pope Urban VIII facing Galileo 165 Galileo Galilei by Mario Leoni (1624) 230 Galileo Galilei, Dialogo (1632): title page 256 Vincenzo Galilei, Dialogo della musica antica (1581): title page 274 Rene Descartes, by an unknown artist 300 Euclid: the geometry of vision 302 Euclidian vision: from Robert Fludd, Utriusque cosmi. . . historia:
Microcosmus (Oppenheim, 1618) 303 The anatomy of the eye (1572) 306 Diagram of the eye, from Roger Bacon, Opus Majus 307 Light rays and the eye, from Roger Bacon, Opus Majus 312 Alberti's grid (1435) 318 A painting of a cross-section of the visual pyramid: from Fludd (1618) 318
Leonardo da Vinci, Codex Atlanticus, f. 337, illustrating his
comparison of the eye with a camera obscura 321 Leonardo da Vinci, Codex D, f. 3v 322 Observing a solar eclipse in a camera obscura (1545) 323 Kepler, Ad Vitellionem paralipomena (Frankfurt, 1604), after
Plater, De corporis humani structura et usu (Basel, 1583) 333 Descartes, La dioptrique (Leiden, 1637), illustrating Kepler's
ocular dioptrics 337 Kepler, Ad Vitellionem paralipomena (Frankfurt, 1604),
vol. 3, prop, xxiii 340 Scheiner, Rosa ursina (Bracciani, 1630), comparing the eye and
a camera obscura with a lens system, and the effects on each of
using further lenses 346 Descartes, La dioptrique (Leiden, 1637), illustrating the transmission of light 351 Scheiner, Oculus (Oeniponti, 1619), showing the structure of the eye 353
This second volume of essays forms a coherent set of studies like the first volume Science, Optics and Music in Medieval and Early Modern Thought published in 1990. Both volumes complement my books Augustine to Galileo: Medieval and Early Modern Science and Robert Grosseteste and the Origins of Experimental Science 1100-1700 and lead into my Styles of Scientific Thinking in the European Tradition: The History of Argument and Explanation Especially in the Mathematical and Biomedical Sciences and Arts (3 volumes, published by Gerald Duckworth & Co. Ltd, London, 1994), and forthcoming Galileo's Arguments and Disputes in Natural Philosophy (with the collabora-tion of Adriano Carugo), and Marin Mersenne: Science, Music and Language. The history of Western science is the history of a vision and an argument, initiated by the ancient Greeks in their search for principles at once of nature and of argument itself. This scientific vision, explored and controlled by argument, and the diversification of both vision and argument by scientific experience and by interaction with the wider contexts of intellectual culture, constitute the long history of European scientific thought. Underlying that development have been specific commitments to conceptions of nature and of science with its intellectual and moral assumptions, accompanied by a recurrent critique. Their diversification has generated a series of different styles of scientific thinking and of making theoretical and practical decisions.
These styles are described and analysed in the opening chapter and exemplified in more detail in those that follow. These deal with scientific objectivity, the historiography of medieval science, Robert Grosseteste and Roger Bacon (Chapter 5 in collaboration with John North), the medieval conception of laws of nature, and the historical relation between rational design in scientific experimentation and in the arts exemplified especially by perspective painting. After a chapter on the place of mathematics in sixteenth-century Italian universities and in Jesuit educational policy, there are five substantial studies of Galileo and his ideals of scientific demonstration and experimentation, of his use of rhetoric, and of his reputation. Two of them, Chapters 10 and 11, were written in collaboration with my colleague Adriano Carugo. Central to them are our discoveries of the use by Galileo of works by Jesuit philosophers at the Collegio Romano or associated therewith, which
have thrown an entirely new and very influential light on Galileo's intellectual biography. These chapters contain the original and authentic account of these discoveries. Next come studies of Mersenne and the origins of language, and of the role of hypothetical modelling in the investigation of hearing and more particularly of vision, with a detailed analysis of the theories and researches of Alhazen, Kepler and Descartes. These complement and bring up to date my long monograph on the subject (1967) republished in Science, Optics and Music. There is a further substantial analysis of historical contexts of arguments from probabilities, from the qualitative treatment found in ancient medicine, ethics and law, through the quantification of probabilities initiated with insurance and commerce in fifteenth-century Italy, given mathematical elegance especially by Pascal, Huygens and Leibniz, developed further in the fields of demography and economics, and applied to a form of evolution by natural selection in the eighteenth century by Maupertuis and finally in crucial detail by Darwin. Concluding chapters deal with scientific language, concep-tions of disease, and the historiography of science.
Some of the papers included in this volume (chs. 3,10 appendix (a), 14, 20) have not been published in English before. The others have been left as they were first printed except for minor corrections. Thus they record stages in the process of discovery and interpretation, as in the chapters on Galileo, especially when dealing with problems of dating, many of them still unsolved. They have been reprinted with continuous pagination, with footnotes at the bottom of the page, and with appropriate revision of internal references. Immediately relevant further bibliography has been added as required at the ends of chapters. An extensive bibliography for the whole subject is included in my Styles of Scientific Thinking. Additions to my own publications, beyond those included in the bibliography of my writings in Science, Optics and Music, are listed below. Finally, once again it is a pleasure to thank all those who provided the occasions for these papers, in Belagio, Athens, Erice, Rome, Cambridge, Mass., Capri, Florence, Paris, Tours, Smith College, Barcelona and Annecy.
A.C. Crombie 30 November 1994 Trinity College, Oxford
Acknowledgements should have been made in Science, Optics and Music to the bibliography published in The Light of Nature: Essays in the History and Philosophy of Science Presented to A.C. Crombie, ed. J.D. North and J.J. Roche. Dordrecht, Martinus Nijhoff Publishers, 1985.
(a) Books on the History of Science
1992 Stili di pensiero scientifico agli inizi dell' Europa moderna.
Napoli, Bibliopolis. Spanish translation by J.L. Barona, Valencia, 1994.
1994 Styles of Scientific Thinking in the European Tradition: The History of Argument and Explanation Especially in the Mathematical and Biomedical Sciences and Arts, 3 vols. London, Gerald Duckworth & Co. Ltd., 1994.
(b) Papers on the History of Science
1990 'Le corps a la Renaissance: Theories of Perceiver and Perceived in Hearing' in Le Corps a la Renaissance: Actes du xxxe Colloque de Tours 1987, sous la direction de J. Céard, M.M. Fontaine, J.-C. Margolin. Paris, Aux Amateurs de Livres, pp. 379-87.
'Expectation and Assent in Seventeenth-Century Scientific Argu-ment: Galileo and Others' (Banfi Lecture, 1989), Istituto Antonio Banfi Annali, iii (1989-90), pp. 11-54
'La Langue maternelle de la science', Alliage: Culture Science -Technique, no. 4 (Eté, 1990), pp. 39-42.
Review of E. Grant and J.E. Murdoch (ed.), Mathematics and its Applications to Science and Natural Philosophy in the Middle Ages (Cambridge, 1987) in English Historical Review, cv (1990), pp. 1007-8.
1990/91 'Expectation, Modelling and Assent in the History of Optics, i: Alhazen and the Medieval Tradition; ii: Kepler and Descartes',
Studies in History and Philosophy of Science, xxi (1990), pp. 605-32, xxii (1991), pp. 89-115
1992 Review of Nicolas-Claude Fabri de Peiresc, Lettres à Claude Saumaise et à son entourage (1620-1637), éd. Agnes Bresson. Firenze, Leo S. Olschki, 1992, Times Literary Supplement, 2 October 1992, p. 23. 1993 The Origins of Western Science', Metascience, n.s. ii, pp. 1-16.
Presentation of Lessico filosofico dei secoli xvii e xviii, Sezione latina, a cura di Marta Fattori con la collaborazione di M.L. Bianchi, fasc.i (Roma, 1992) at the Warburg Institute, London, 3 May 1993, in Nouvelles de la Republique des Lettres, (1993)-ii, 102-4.
1994 Reviews of Elspeth Whitney, Paradise Restored: The Mechanical Arts from Antiquity through the Thirteenth Century (Philadelphia: Amer-ican Philosophical Society, Transactions lxxx.1, 1990) and Georges Minois, L'Eglise et la Science: Histoire d'un malentendu. De Saint Augustine a Galilee (Paris, 1990) in English Historical Review, cix (1994), pp. 136-8; and of Guiseppe Olmi, L'inventario del mondo: Catalogazione della natura a luoghi delsapere nella prima etá moderna (Bologna, 1992) in Journal of the History of Collections, forthcoming. 'The Greek Origins of European Scientific Styles', Ad familiares: The journal of the Friends of Classics, vii (1994), pp. xii-xiv.
'The History of European Science', New European: European Business Review, xciv (1994), pp. ii-v.
1995 'Historical Perceptions of Medieval Science' in Federico II e le Scienze: Proceedings of the International Seminar on Frederick II and the Mediterranean World, a cura di A. Paravicini Bagliani. Palermo, Sellerio, pp. 15-24.
'Marin Mersenne et les origines du langage' in Nature, histoire, société: Essais en hommage a Jacques Roger, prés. par C. Blanckaert, J.-L. Fischer, J. Rey. Paris, Editions Klincksieck, pp. 35-46.
'Boundaries of normality' in Malatia i cultura: Seminari d'Estudis sobre la Ciència, ed. J.L. Barona (Valencia, 1995), pp. 11-17. 'Per una antropologia històrica del saber científic', interview by Marc Borràs in Mètode: Revista de difusió de la investigació de la Universitat de València, ix (1995), pp. 14-17.
'Commitments and Styles of European Scientific Thinking' in History of Science, xxiii (1995), pp. 225-38.
'Univers' (with J.D. North) in Les caractères originaux de I'Occident medieval, éd. J. Le Goff, J.-C. Schmitt. Paris, Librairie Arthème Fayard, forthcoming.
"Philosophical Commitments and Scientific Progress" in The Idea of
Progress (Academia Europea conference 1994), forthcoming.
(c) Editorships
Editor, 1949-54 of The British Journal for the Philosophy of Science. Joint founder and editor of History of Science: A Review of Literature, Research and
Teaching, Cambridge, W. Heffer and Sons, 1962-72; Science History
Publica-tions 1973- .
(d) Scientific Papers
Papers on (i) interspecific competition (an experimental and mathematical analysis on some aspects of ecology and natural selection) and (ii) the physiology of the chemical sense-organs in insects.
1941 On Oviposition, Olfactory Conditioning and Host Selection in
Rhizopertha dominica Fab. (Insecta, coleoptera)', Journal of Experi-mental Biology, 18, pp. 62-79.
1942 'The Effect of Crowding upon the Oviposition of Grain-Infesting Insects',/. Exp. Biol., 19, pp. 311-40.
1943 'The Effect of Crowding upon the Natality of Grain-Infesting Insects',
Proceedings of the Zoological Society of London, A, 113, pp. 77-98.
1944 'On Intraspecific and Interspecific Competition in Larvae of Gramini-vorous Insects', 7. Exp. BioL, 20, pp. 135-51.
'On the Measurement and Modification of the Olfactory Responses of Blow-Flies', /. Exp. BioL, 20, pp. 159-66.
'Sensillae of the Adults and larvae of the Beetle Rhizopertha
dominica Fab. (Bostrichidae)', Proceedings of the Royal Entomo-logical Society of London A, 19, pp. 131-2.
1945 'On Competition between Different Species of Graminivorous Insects', Proceedings of the Royal Society, B, 132, pp. 362-95. 1946 'Further Experiments on Insect Competition', Proc. Roy. Soc., B,
133, pp. 76-109.
1947 'The Behaviour of Wireworms in Response to Chemical Stimulation' [with W.H. Thorpe, R. Hill and J.H. Darrah], /. Exp. BioL, 23, pp. 234-66.
'The Chemoreceptors of the Wire worm (Agriotes spp.) and the Relation of Activity to Chemical Composition' [with J.H. Darrah], J.
Exp. Biol. 24, pp. 95-109.
'Interspecific Competition', Journal of Animal Ecology, 16, pp. 44-73.
A little I can read.
Designed in the Mind: Western Visions of
Science, Nature and Humankind
When we speak today of natural science we mean a specific vision created within Western culture, at once of knowledge and of the object of that knowledge, a vision at once of natural science and of nature.1 We may trace
the characteristically Western tradition of rational science and philosophy to the commitment of the ancient Greeks, for whatever reason, to the decision of questions by argument and evidence, as distinct from custom, edict, authority, revelation, rule-of-thumb, on some other principle or practice. They developed thereby the notion of a problem as distinct from a doctrine, and the consequent habit of envisaging thought and action in all situations as the perception and solving of problems. By deciding at the same time that among many possible worlds as envisaged in other cultures, the one world that existed was a world of exclusively self-consistent and discoverable rational causality, the Greek philosophers, mathematicians and medical men committed their scientific successors exclusively to this effective direction of thinking. They closed for Western scientific vision the elsewhere open questions of what kind of world people found themselves inhabiting and so of what methods they should use to explore and explain and control it. They introduced in this way the conception of a rational scientific system, a system in which formal reasoning matched natural causation, so that natural events must follow exactly from scientific principles, just as logical and mathematical conclusions must follow from their premises. Thus they introduced, in parallel with their conception of causal demonstration, the equally fundamental conception of formal proof. From these two conceptions all the essential character and style of Western philosophy, mathematics and natural science have followed. The exclusive rationality so defined supplied the presuppositions and came to supply the methods of reasoning alike in purely formal discourse and in the experiential exploration of nature. Hence it offered rational control of subject-matters of all kinds, from mathematical to material, from ideas to things. A similar characteristic style is evident over the whole range of Western intellectual and practical enterprise. We have then in Western scientific culture, as an object of study to which we its students at the same time inextricably belong, a highly intellectualized and integrated whole, designed in
the mind like a work of art, not all at once but over many generations of interaction between creative thinking and testing, between programmes and their realization or modification or rejection.
But if we insist upon the cultural specificity of the Western scientific tradition in its origins and initial development, and upon its enduring identity in diffusion to other cultures, we do not have to look far below the surface of scientific inquiry and its immediate results to see that the whole historical process has gone on in a context of intellectual and moral commitments, expectations, dispositions and memories that have varied greatly with differ-ent periods, societies and also individuals. These have affected both the problems perceived and the solutions found acceptable, and also the evalu-ations of desirable or undesirable ends and their motivevalu-ations. The whole historical experience of scientific thinking is an invitation to treat the history of science, both in its development in the West and in its complex diffusion through other cultures, as a kind of comparative historical anthropology of thought. An historical anthropology of science must be concerned before all with people and their vision. The scientific movement offers an invitation to examine the,identity of natural science within an intellectual culture, to distinguishrihat from the identities of other intellectual and practical activities in the arts, scholarship, philosophy, law, government, commerce and so on, and to relate them all in a taxonomy of styles. It is an invitation to analyse the various elements that make up an intellectual style in the study and treatment of nature: conceptions of nature and of science, methods of scientific inquiry and demonstration diversified according to the subject-matter, evaluations of scientific goals with consequent motivations, and intellectual and moral commitments and expectations generating attitudes to innovation and change. The scientific thinking found in a particular period or society or individual gets its vision and style from different but closely related intellectual or moral commitments or dispositions. We may distinguish three.
(1) First there have been conceptions of nature within the general scheme of existence and of its knowability to man. These in turn have been conditioned by language. The original Greek commitment entailed the replacement of conceptions of nature as an arbitrary sociological order maintained by personified agents, found in all ancient cosmologies and cosmogonies, with the conception of an inevitable order established by an exclusive natural causality. In the succession competing for dominance in subsequent Western thought, nature has been conceived as a product of divine economy or art with appropriate characteristics of simplicity and harmony, as a consequence of atomic chance, as a causal continuum, as a workshop of active substantial powers, as a passive system of mechanisms, as an evolutionary generation of novelty, as a manifestation of probabilities.
Any language itself embodies a theory of meaning, a logic, a classification of experience in names, a conception of both perceiver and perceived and their relation, and of relations in space and time. Philology can be an indispensable guide to theoretical ideas and real actions. The expression of a system of science in a language may not entail an immediate critique of the fundamental structure of that language, yet its vocabulary and syntax may have to be modified to provide for the conceptual and technical precision required by the science developing within it. Thus a new terminology had to be devised in medieval and early modern Latin to accommodate the new kinematic and dynamic conceptions, especially of functions, of instantaneous change and of rates of change, which could scarcely be expressed in the classical logic and syntax of subject and predicate. Terminology may have had to be revised to detach its specific scientific meaning from its source in common but inadequate or misleading analogies. "The word current", wrote Michael Faraday,2 "is so expressive in common language that when applied in the consideration of electrical phenomena, we can hardly divest it sufficiently of its meaning, or prevent our minds from being prejudiced by it". For the same reason he replaced "pole", inconveniently suggesting attraction, with the neutral "elec-trode", in a new terminology devised with the aid of William Whewell to fit the precise context of electro-chemistry. John Tyndall3 in his attractive account of Faraday as a discoverer exemplified a familiar historical process when he described how, in this new science, "prompted by certain analogies we ascribe electrical phenomena to the action of a peculiar fluid, sometimes flowing, sometimes at rest. Such conceptions have their advantages and their disadvan-tages; they afford peaceful lodging to the intellect for a time, but they also circumscribe it, and by-and-by, when the mind has grown too large for its lodging, it often finds difficulty in breaking down the walls of what has become its prison instead of its home." Thus a radically new technical language may be made up, precisely symbolized as first for mathematics and music and later for many other sciences and arts. The result may be a special language fundamen-tally different in intention from that implicit in the common language of the society from which it originated, but still a language that may be learned and understood in any society and may convey to it objectively communicable knowledge.
Must science in different linguistic cultures always acquire differences of logical form, and must the grammatical structure of a language always impose its ontological presuppositions on the science developing within it? While the technical language of science has often been developed partly to escape from just such impositions, philology can be an accurate guide to implicit or explicit
intellectual commitments of this kind and to their changes.
The West learnt from the Greeks to look for causal continuity in events both physical and moral, and this has structured its natural and moral philosophy
alike and its whole tradition of dramatic literature and music since Antiquity. Japanese thinking, now in exemplary possession of Western science and music, seems traditionally by contrast to have accepted events in their individual existential discontinuity, impressionistically unrelated to before and after, with no general abstract term for nature, but each thing the subject of personal knowledge and companionship, not of mastery either by thought or action. The whole question might throw an interesting light in our philosophical anthropology upon a question central to the whole Western debate: that of distinguishing the argument giving rational control of subject-matter from an implication of the existence of entities appearing in the language used, or, more generally, that of distinguishing a rational structure of nature from that of the organizing human mind.
(2) A second kind of intellectual commitment affecting scientific style has been to a conception of science and of the organization of scientific inquiry. Two different traditions of scientific organization and method began in Antiquity. The dominant Greek mathematicians saw as their goal the reduc-tion of every scientific field to the axiomatic model of their most powerful intellectual invention, geometry. At once alternative and complementary to this was the much older medical and technological practice of exploring and recording by piecemeal observation, measurement and trial. The medieval and early modern experimental natural philosophers combined both traditions, to transform the geometrical pattern by an increasing preoccupation with quantitative experimental analysis of causal connections and functional rela-tions. Yet a different pattern came from intellectual satisfaction in mathemati-cal harmonies rather than causal processes. Other modes of intellectual organization assimilated analysis for scientific investigation to that for artistic construction, or looked for probabilities or for genetic origins and derivations. All generated scientific systems made up of theories and laws and statements of observations, providing particular explanations and solutions of problems within the framework of a general conception of nature and science, along with scientific methods diversified by the diversity both of general commit-ments and of particular subject-matters of varying complexity.
The commitments of a period or group or individual to general beliefs about nature and about science, combined with the technical possibilities available, have regulated the problems seen, the questions put to nature, and the acceptability of both questions and answers. Such commitments have directed research towards certain types of problem and towards certain types of discovery and explanation, but away from others. They have both guided inquiry and supplied its ultimate irreducible explanatory principles. By taking us beneath the surface of immediate scientific results, they help us to identify the conceptual and technical conditions, frontiers and horizons making certain discoveries possible and explanations acceptable to a generation or group, but
others not, and the same not to others. More specifically a discovery or a theory or even a presentation of research may open fresh horizons but at the same time close others hitherto held possible. Dominant intellectual commit-ments have made certain kinds of question appear cogent and given certain kinds of explanation their power to convince, and excluded others. They established, in anticipation of any particular research, the kind of world that was supposed to exist and the appropriate methods of inquiry. Such beliefs, taken from the more general intellectual context of natural science, have regulated the expectations both of questions and of answers, the form of theories and the kinds of explanatory entities taken into them, and the acceptability of the explanations they offered. They established in advance the kind of explanation that would give satisfaction when the supposedly discoverable had been discovered. They have been challenged not usually by observation, but by re-examining the metaphysics or theology or other general beliefs assumed. In this process the cogency of such worlds might change from generation to generation as each nevertheless added to enduringly valid scientific knowledge.
(3) A third kind of intellectual and moral commitment has concerned what could and should be done. This in its diverse modes has followed from diverse evaluations of the nature and purpose of existence and hence of right human action. It has been linked with dispositions generating an habitual response to events, both internally within scientific thinking itself, and externally in the responses of society: dispositions to expect to master or to be mastered by or simply to contemplate events, to change or to resist change, to anticipate innovation or conservation, to be ready or not to reject theories and to rethink accepted beliefs and to alter habits. Such dispositions have been both psychological and social. They may be specified by habitual styles and methods both of opposition and of acceptance. They may characterize a society over the whole range of its intellectual and moral behaviour, of which its natural science is simply a part.
The primary focus, for example, of medieval and early modern Christian as of Islamic culture and society on the teaching and preservation of theological truth could scarcely fail to condition all human inquiries. Sensitive impli-cations of natural philosophical and metaphysical questions and doctrines placed the whole of intellectual life within the political framework and control of a moral cosmology.The medieval Christian theological hierarchy of dignity within that cosmology, as also Islamic attitudes to the visual representation of natural objects, took that control as far as aesthetic style. Given the dual source of human knowledge in the divine gifts of true reason and of undeniable revelation, the whole enterprise made an urgent issue then of error, of the possibility of error in good faith, of the attitude to be taken to
unpersuadable infidels and irredeemable heretics, of the commitments and expectations of disagreement as well as agreement.
In all this, and in the whole scientific movement considered in the context of society and of communication, persuasion has been as important as proof. The use of persuasive arguments to reinforce or to create the power of ideas to convince, especially when the ideas were new and the audience uncertain or unsympathetic, has been well understood by some of the greatest scientific innovators. Galileo and Descartes were both masters of the current rhetorical techniques of persuasion. Galileo devoted at least as much energy to trying to establish the identity of natural science within contemporary intellectual culture as to solving particular physical problems. He conducted all his controversies at two levels: one was concerned with the particular physical problem in question; the other was concerned with an eloquent advocacy of his conception of natural science as an enterprise in solving problems and finding scientific explanations distinct from the philosophical or theological exegesis of authorities and texts, from a literary exercise, from a commercial or legal negotiation, from magic, and so on. His test of a general explanation was its ability to incorporate the solution of particular problems. Descartes argued likewise at two levels, and this indeed was a general necessity in a period when the intellectual identity of the contemporary scientific movement was still open to misunderstanding by the learned world at large and when its methods and accepted styles of reasoning were still to some extent being established. Again, Charles Lyell, himself a lawyer, set out like a skilful lawyer to present his uniformitarian conception of geology as the only acceptable one and to discredit its hitherto accepted catastrophic rival. Charles Darwin similarly set out his argument in the Origin of species for evolution by natural selection like a legal brief: marshalling the evidence, demolishing rival explanations, propos-ing his own solution, raispropos-ing difficulties against it, meetpropos-ing them one by one, and finally concluding that his was the only plausible and acceptable explana-tion that could account for all the various categories of fact that had to be considered. By presenting his arguments in the wake of the statistical analysis of human economics which provided the persuasive analogy, Darwin was able to establish at one and the same time his scientific explanation by natural selection and a statistical conception of the economy of nature which belief in providential design had hitherto made widely unacceptable in biology. Persua-sion has obviously been aimed at the diffuPersua-sion of scientific ideas, both at the sophisticated level of the scientific community and also among the general public.
Change in ideas has come about more easily in some scientific situations, periods and societies than in others. It has been easier to reject particular theories within an accepted system of general doctrine than to take the drastic step of rejecting the whole doctrine. The disposition to change, which has been
so marked a characteristic of the whole modern history of the West, became within the same culture an essential part of the scientific movement over a period when innovation and improvement were also becoming the intellectual habit in art, theology, philosophy, law, government, commerce and many other activities. It was a matter of individual as well as collective behaviour: Kepler, for example, contrasts notably with some of his contemporaries and opponents in controversy by his readiness to sacrifice a favourite theory to contrary evidence. The conscious cultivation and reward of a disposition towards innovation began in Western society perhaps first in the technical arts and philosophy, but it has been transmitted elsewhere mainly with Western commerce and science.
A comprehensive historical inquiry into the sciences and arts mediating man's experience of nature as perceiver and knower and agent would include questions at different levels, in part given by nature, in part made by man. These correspond to the three kinds of commitment. Thus at the level of nature there is historical ecology: the reconstruction of the physical and biomedical environment and of what people made of it. The sources and problems of historical ecology, both human and physical, range from those of archaeology and palaeopathology to those of the history of climate, techno-logy, medicine, agriculture, travel and art. Historical problems at all levels require scientific and linguistic knowledge to control the view of any present recorded through the eyes and language of those who saw it. They may require also historical knowledge of religion and of artistic style, economic theory, and other analytical disciplines. At all levels comparative historical studies of the intellectual and social commitments, dispositions and habits, and of the material conditions, that might make scientific activity and its practical applications intellectually or socially or materially easy for one society, but difficult or impossible for another, have an immediate relevance for the diverse cultures brought into contact with the science, medicine, technology and commerce of our contemporary world.
It is only comparatively recently, and only in highly industrialized societies, that science and technology have risen to a dominant position among the vastly various concerns and interests that throughout history have moved men to thought and action. What have been the numbers, social position, edu-cation, occupations, institutions, private and public habits, motives, opportu-nities, persuasions and means of communication of the individuals taking part in scientific activities in different periods and societies? What critical audience has there been to be convinced by, use, transmit, develop, revise or reject their arguments? Where scientific and analogous inquiries have interested only a scattered minority, what opportunities have existed for establishing agreement on principles and methods, or even continuity between generations? How, for example, were these maintained in the ancient Mediterranean, or in China or
India? In comparison, what intellectual or moral or practical commitments motivated the teaching and learned institutions of medieval Islam and of medieval and early modern Christendom, and came in the last to establish effective conditions of education and research for an explicit scientific com-munity? How have the conditions for science and for technology differed? What intellectual needs or habits or intentions or social pressures have there been within different philosophical or scientific or technical groups to bring about a consensus of opinion in favour of innovation or of conservation?
How have scientific ideas and activities been located within the values of society at large? What has been the intellectual or moral or practical value given to science in different societies, within a range of interests so divergent as those indicated, for example, by a predominant concern with a theological scheme of human responsibility and destiny, by the cultivation of the arts or of literary learning or of logic and philosophy, by the pressures and expediencies of politics, by the needs of war, trade, industry, transport or medicine? What has been the appeal of pure intellectual curiosity and philosophical satisfac-tion, of a religious search for God in nature, of a desire for intellectual or moral or social or political reform, of utility in the senses either of the material improvement of the human condition or of industrial or commercial or political or military power or gain? What social or commercial or political interests have promoted or resisted scientific research and technical inno-vation, and the diffusion and application of ideas, discoveries and inventions? To what extent does innovation breed innovation? What was the cost-effectiveness of the inventions described in histories of technology, who used them, and with what consequences? It would be relevant to compare the criteria of evidence and decision used in science or in medical diagnosis and prognosis with those used in commerce and industry, in law courts, and in choice of policies by governments. Relevant also are mentalities indicated by philosophical and social programmes and responses in relation to their social, economic and sometimes military context. So too are the intellectual and social responses of society at large to making man an object of scientific inquiry and treatment.
Likewise what external pressures and internal dispositions have operated in the intellectual and practical responses of one culture to another, of Islam to Greek thought, of medieval Western Christendom to Islam and to farther Asia, of early modern Europe to China and Japan and India and the New World, of Japan in its early history to China and in the sixteenth and nineteenth centuries to the West, of China throughout its history to any other culture, of the so-called developing countries now to the industrially developed?
The essence of effective scientific thinking has been the advancement of knowledge through the identification of soluble problems. What have been the
sources of new intellectual perceptions? How have the intellectual commit-ments or dispositions or habits or the technical potentialities of an individual or a group or period either promoted or discouraged creative discovery and technical invention? How have these interacted with the conditions for intellectual change or conservation in the philosophical, technical, social and materal ambience of science? To what extent has the internal logic of science taken over from features of this ambience, accidental analogies, or suggestions for new hypotheses or styles of thinking? What has been the part played in the initiation of progress by breaches of conceptual frontiers leading to asking new questions, seeing new problems, accepting new criteria of valid demonstration and cogent, satisfactory explanation? Scientific thinking has commonly pro-gressed through periods of critical analysis bringing novel forms of speculation about the discoverable in nature in anticipation of technical inquiry. Obvious examples are the critique of the Aristotelian doctrine of qualities and causa-tion preceding the new science of mocausa-tion established from Galileo to Newton, the atomic speculations preceding the quantitative atomic theory promoted by John Dalton, and the evolutionary speculations preceding the scientific organization of the evidence and theory finally achieved by Charles Darwin. The older conceptions were discarded and the new first entertained by rethinking; but the new ideas became established as scientific knowledge only by technical scientific research. Only after that were their speculative precur-sors given a retrospective scientific significance.
Of the essence of the Western scientific tradition, and of the evidence for its history, have been the self-conscious assessments of its presuppositions, performance and prospects that have continued through many changes of context from Archytas and Aristotle down to the latest disputes among scientists, philosophers and historians. The critical historiography of science has been an integral part of the scientific movement itself. Such assessments both of current science and of the history of science have had various purposes. Those made in medieval and early modern Europe aimed usually to monitor the identity and intellectual orientation of the contemporary scientific movement and to define its methods and criteria of acceptability of questions and answers. They were made during a long period when increasing scientific experience, historical scholarship, and awareness of other contemporary cultures enabled Europeans to measure their own scientific orientations and potentialities against those of diverse earlier and contemporary societies.
The range of modern assessments points to the range of sources for an interpretation. The radical variations in contemporary assessments and their changes with time and context and individual disposition provide unique and indispensable primary evidence in historically taking the measure of the intellectual and technical and moral equipment available in any scientific situation. An habitual search during this period at once for the best form of
science, and for its best ancient model, projected the earlier into the contem-porary tradition but with extended power. Through the variations of the scientific movement there has run a consistency of development in conceptions of explanation and method. The growth of particular scientific knowledge has carried in its wake a growth of general understanding of scientific thinking and its varieties. This consistency clarifies the historical variety of accepted explanations and methods diversified by intellectual commitments and subject-matters.
Both in the perception and solution of problems within the theoretical and technical possibilities available, and in the justification of the enterprise whether intellectual or practical or moral, the history of science has been the history of argument. Scientific argument forms the substance of the scientific movement, a discourse using experiment and observation, instruments and apparatus, mathematical reasoning and calculation, but with significance always in relation to the argument. The scientific movement brought together in its common restriction to answerable questions a variety of scientific methods, or styles of scientific inquiry and demonstration, diversified by their subject-matters, by general conceptions of nature, by presuppositions about scientific validity, and by scientific experience of the interaction of pro-grammes with realizations. Throughout, methods of yielding accurately reproducible results were required equally by the practical commitment of technology and the arts to the control of materials, and by the theoretical commitment of science to establishing regularities or causal connections within a common form of demonstration. An historian needs to ask both what theories of scientific method contributed to science, and what methods were used by scientists. We may distinguish in the classical scientific movement six styles of scientific thinking, or methods of scientific inquiry and demon-stration. Three styles or methods were developed in the investigation of individual regularities, and three in the investigation of the regularities of populations ordered in space and in time. Each arose in a context in which an assembly of cognate subject-matters was united under a common form of argument.
Thus (i) the simple method of postulation exemplified by the Greek mathematical sciences originated within the common Greek search for the rational principles alike of the perceptible world and of human reasoning. This was the primary ancient model, uniting all the mathematical sciences and dependent arts, from optics and music to mechanics, astronomy and cartogra-phy, (ii) The deployment of experiment, both to control postulation and to explore by observation and measurement, was required by the scientific search for principles in the observable relations of more complex subject-matters. Starting with the Greeks, the strategy of experimental argument was elabor-ated in medieval and early modern Europe as a form of reasoning by analysis
and synthesis in which the point at which experiment was brought into the argument, either for control or for exploration, was precisely defined. Moves towards quantification in all sciences may be traced to the general European growth both of mathematics and of the habits of measurement and recording and calculation arising from need in some special sciences, as in astronomy, and in the practical and commercial arts, where new systems of weights and measures and of arithmetical calculation were first developed. The scientific experimental method derived from the union of these practical habits with the logic of controls, with further quantification through new techniques of instrumentation and mathematical calculation. The rational experimenter was the rational artist of scientific) inquiry, (iii) Hypothetical modelling was developed in a sophisticated form first in application to early modern perspective painting and to engineering, and was then transposed from art into science as likewise a method of analysis and synthesis by the construction of analogies. The recognition that/in the constructive arts theoretical design must precede material realization anticipated the scientific hypothetical model. Each proceeding to a different end, artist and scientist shared a common style. The imitation of nature by art then became an art of inquisition; rational design for construction became rational modelling for inquisitorial trial, (iv) Taxonomy emerged first in Greek thought as a logical method of ordering variety in any subject-matter by comparison and difference. The elaboration of taxonomic methods and of their theoretical foundations may be attributed to the need to accommodate the vast expansion of known varieties of plants and animals and diseases following European exploration overseas, with attempts to relate diagnostic signs and symptoms to their causes and to discover the natural system that would express real affinities, (v) The statistical and probabilistic analysis of expectation and choice developed in early modern Europe again took the same forms whether in estimating the outcome of a disease, of a legal process, of a commercial enterprise, or natural selection, or the reasonableness of assent to a scientific theory. The subject-matter of probability and statistics came to be recognized through attempts to accom-modate within the context of ancient and medieval logic situations of contingent expectation and uncertain choice, followed by the early modern discovery of the phenomenon of statistical regularities in adequately numerous populations of economic and medical and other events. Thus uncertainty was mastered by reason and stabilized in a calculus of probability, (vi) The method of historical derivation, or the analysis and synthesis of genetic development, was developed originally by the Greeks and then in early modern Europe first in application to languages and more generally to human cultures, and afterwards to geological history and to the evolution of living organisms. The subject-matter of historical derivation was defined by the diagnosis, from the
common characteristics of diverse existing things, of a common source earlier in time, followed by the postulation of causes to account for the diversification from that source.
Clearly all this scientific diversity can be understood only within the diversity and the changes of thought in the whole historical context. The history of science is the history of argument: an argument initiated in the West by ancient Greek philosophers, mathematicians and physicians in their search for principles at once of nature and of argument itself. Of its essence have been its genuine continuity, even after long breaks, based on the study by any generation of texts written by its predecessors, its progress equally in scientific knowledge and in the analysis of scientific argument, and its recurrent critique of its moral justification. A subtle question is what continued and what changed through different historical contexts, in the scientific argument and in the cultural vision through which experience is mediated, when education and experience itself could furnish options for a different future. Styles of thinking and making decisions, established with the commitments with which they began, habitually endure as long as these remain. Hence the structural differences between different civilizations and societies and the persistence in each despite change of a specific identity. Hence the need for historical analysis in the scientific movement of both continuity and change. These like most human behaviour begin in the mind, and we its historians who belong at the same time to its history must look in a true intellectual anthropology at once with and into the eye of its beholder.
REFERENCES
1. This paper is based on the historiographical introduction to my book, Styles of scientific
thinking in the European tradition (Gerald Duckworth, London, 1994), which contains
full documentation and bibliography; cf. also A. C. Crombie, "Science and the arts in the Renaissance: The search for truth and certainty, old and new", History of science, xviii (1980), 233-46; idem, "Historical commitments of European science", Annali del' Istituto
e Museo di Storia della Scienza di Firenze, vii, part 2 (1982), 29-51; idem, "What is the
history of science?", History of European ideas, vii (1986), 21-31; idem, "Experimental science and the rational artist in early modern Europe", Daedalus, cxv (1986), 49-74;
idem, "Contingent expectation and uncertain choice: Historical contexts of arguments
from probabilities" in The rational arts of living, ed. by A. C. Crombie and N. G. Siraisi (Northampton, Mass.: Smith College studies in history, 1987): the first three of these papers are included in A. C. Crombie, Science, optics and music in medieval and early
modern thought (Hambledon Press, London, 1990).
2. Michael Faraday, Experimental researches in electricity, i (London, 1839), 515; cf. pp. 195 ff. 3. John Tyndall, Faraday as a discoverer (London, 1868), 53-55.
The Western Experience of Scientific Objectivity *
At a depressing period of the Pelopennesian War, Thucydides included in his famous account of the moral disintegration of society in revolution two points of immediate relevance to a discussion of the European experience of scientific objectivity. Revolution had brought many and terrible sufferings upon the Greek cities. Unscrupulous men-dacity and opportunist treachery masqueraded as superior cleverness, the sweeter if a rival trusting a pledge of reconciliation were taken off his guard. Anyone who excelled in evil and anyone who «prompted to evil someone who had never thought of it were alike commended*. Conspirators used fair words for guilty ends with cynical confidence that others would hypocritically welcome them as cover for their own moral cowardice or indifference. United only through complicity in crime, greed and envy against the moderate and the honest, «neither had any regard for true piety, yet those who could carry through an odious deed under the cloak of a specious phrase received the higher praise». 1 Among all this violence against both truth and person he noted interestingly : «Words had to change their ordinary meaning in relation to things and to take that which men thought fit*. And, he argued, these calamities of behaviour «have occurred and always will occur as long as the nature of mankind remains the same». For «human nature, always rebelling against the law and now its master, gladly showed itself ungoverned in passion», setting gain above justice and revenge above religion : «For surely no man would put revenge above religion, and gain before innocence of wrong, had not envy swayed him with her blighting power»2. It was the same in the plague of Athens. Strong and weak were swept indifferently away, victims withunquench-* 'H (ivaxotvoxjis aveYV<J>a6y) UTT& TOU xaOvj^ToO ERWIN SCUEUCU, 8i6n 6 et<rifjY»)T7)<; x<oXu6(jievo^ 8&v ^8uv/)0yj vA TrapaaTfj. 'Q? £x Toii-rou, dTcdvTO? TOO
elcnqyi')-TOU, 8&V iTttfJXOXoiiGlJCS au£)f)TY)(ItS.
1. Peloponnesian War, iii.82. 2. Ibid, iii.84.
able thirst drank much or little with common failure of relief, physicians could find no remedy and perished themselves, prayers and other mea-sures all proved equally futile and were given up, and men thus bereft of fear of any law divine or human «now coolly ventured on what they had formerly done in a corner*1. Yet from those who had suffered and
recovered from the plague, the sick and dying received help and compas-sion. Influenced by medical thought, Thucydides looked for the causes of social as of individual disorders in a theory of human nature, expres-sing in stable language the dependability of natural law. He offered a commitment to reasoned beliefs and actions against which to measure the motivation of behaviour. This may suitably introduce the subject of my brief contribution to this discussion of objectivity and culture, which is the interaction of reason, belief and motive in the history of science, medicine and technology.
I shall argue that in order to understand our culture, we are not only advised but obliged to study the intellecutal attitudes and achieve-ments of societies that have formed its history remote in time and see-mingly remote in character from the immediate present. Yesterday's events can be the least relevant to educated understanding. In the spirit of a symposium evidently based on the belief that one main reason for studying history is to throw light upon ourselves, a belief which I fully share, there are various ways of doing this in the history of science, medicine and technology. It hardly now needs saying that in this field, as mutatis mutandis in all intellectual and social history whether of philosophy, law, theology or whatever, the particular thinking found in any period can be properly understood by us only by relating it to the categories in which nature, and man as a participant in and student of nature, were understood in the societies and by the individuals with which we are concerned. We can study the history of science as a kind of intellectual anthropology. We can make a natural history of intellec-tual and moral behaviour in situations presenting questions for decision. The enlightenment that we may derive from this kind of historical experience is like that we get from foreign travel, especially outside the areas of Western culture. We expose ourselves to the surprise of disco-vering that thinkers so effective in solving problems which we seem to be able to recognize should be able to do so within the context of such a variety of aims, categories and presuppositions, mostly very different from our own. We encounter also societies and individuals who find
intellectual satisfaction in categories of thought and explanation not aimed at solving scientific or technical problems at all but expressing some quite different purpose. Yet in looking for a comparative history or anthropology of approaches to nature, putting ourselves into the minds of those we are studying and trying to understand their questions, we need to control relativity by the contrasting light of the objective continuity of cultural tradition.
Science has developed in the characteristically rational Western tradition as an approach to nature effectively competent to solve prob-lems. Before the general direction towards scientific knowledge had been decided, either in antiquity or in early modern times, two essential general questions remained open. It was an open question what kind of world men found themselves inhabiting, and so it was also an open question what methods they should use to explore, explain and control it. The characteristically Western tradition of rational science and philosophy can be dated from the ancient Greek commitment to the decision of questions by argument and evidence, as distinct from custom, edict, authority, revelation, or some other source. The Greek philosophers and mathematicians at the same time committed the Western tradition to the belief that among many possible worlds, the world that exists is a world of exclusively self-consistent and discoverable rationality. In this way they introduced the fundamental conception of a scientific system, separately for each category of nature and collectively for every category. Pride in self-reliant intelligence, in skill of mind and hand which gave man mastery of earth and sea, of other living creatures, and of such difficult arts and sciences as writing, mathematics, astro-nomy and medicine, appears with the first Greek achievements in these fields in the fifth century B.C., notably in the Prometheus of Aeschylus. In the grasp and technical development of the logic of proof and decision by the ancient Greek philosophers, mathematicians and medics we may see the origins of our scientific tradition. They introduced decision into speculations about nature. The one world that actually exists did so in one discoverable way, which excluded others. Scientific thinking has proceeded and scientific knowledge has progressed ever since by such a logic of either — or, by decisions both about the general nature of the world and about particular questions each of which has committed the future towards one line of theory and away from others. Science has been recognized since Aristotle and Archimedes as a cumulative prog-ress of knowledge, even through periods of the darkest gloom about the
moral regress of mankind. 1 These rational commitments applied
more-over as much to decisions about moral values and principles showing what ought or ought not to be done, as to the decisions of science about what was or was not the case. Aristotle meant his ethics to be derived as systematically from a theory of human nature as his physics was from a theory of matter and causation.
To understand any historical culture we must then study its intel-lectual orientation and re-orientations through long tradition. The recovery of our own scientific culture after periods of external disaster or internal confusion has been the recovery of rational decision. In such a process we may see the origins of modern science in the redisco-very, exegesis and elaboration of the Greek model by medieval and early modern Europe. The rediscovery was made by a new society, with a different view of man and his place in nature and his destiny, a dif-ferent theology and a difdif-ferent economy, but it was seen first, in the twelfth century, as a continuation of the ancient scientific movement. «Nothing is difficult unless you despair...», wrote the Englishman ADELARD OF BATH, translator into Latin of Euclid's Elements of
Geo-metry and author of two works presenting his vision of natural
philo-sophy early in that century; «Therefore hope and you will find the capability. For I shall be the more able to shed light on the matter, from the assumption of the constancy and certainty of principle*.2 Looking forward from the shoulders of giant predecessors, 3 ADELARD and his contemporaries saw unlimited potentialities for the elaboration of scientific knowledge long before these were actually discovered in application to any of the numerous and diverse new problems and subject matters which we can now look back on. ADELARD'S countryman ROGER
1. Cf. E. R. DODDS, The Ancient Concept of Progress (Oxford, 1973) 1 sqq.; A. G. GROMBIE, «Some attitudes to scientific progress : ancient, medieval and early modern», History of Science, xiii (1975) 213 sqq., and also for the argument above Scientific Change, Introduction (London, 1963) 1 sqq., «Historical commitments of biology», The Britsh Journal for the History of Science, iii (1966) 97 sqq.
2. ADELARDUS VON BATH Quaestiones naturales, ed. M. MULLER (Beitrage zur Geschichte der Philosophic des Mittelalters, xxxi.2; Minister, 1934) 58; cf. T. STIEFEL, «The heresy of science : a twelfth-century conceptual revolution*, Isis , ixviii (1977) 347 sqq.
3. Cf. CROMBIE, «Some attitudes...» (1975) 220, «Historians and the scientific revolution*, Physis, xi (1969), and also «The relevance of the middle ages to the scientific movement)) in Perspectives in Medieval History, ed. K.F. DREW and F. S. LEAR (Chicago, 1963) 35 sqq.; citing myself here and elsewhere for ease of refe-rence and further bibliography.
BACON in the next century likewise looked to the recovery of a greater past as the first step towards a happier future, and this remained the common outlook of Christendom until some four hundred years later when modern scientific discovery had got confidently under way.
Programmes for intellectual reform such as those of ROGER BACON and FRANCIS BACON, DESCARTES and others before and many since throw a special light on an essential characteristic of the Western scien-tific tradition : its persistent attention to the definition of norms of rational thought, applying to every kind of subject-matter and every aspect of life. The light may be as special as the reforming vision and historians are well advised to combine it with that of established contem-porary practices. Together they illuminate the beliefs and motives arising from the whole intellectual and social ambience, as well as the scientific experience, which have given diversity to definitions of the rational, the possible, the desirable and the acceptable. ROGER BACON'S vision of rational human happiness and dignity foresaw the restoration of one true wisdom founded on the Scriptures equally with rational science as he conceived it. * Visions of happiness, of science and of BA-CON himself have all since changed selectively with human expectations. Discussions of the discoverable and the discovered as well as of the re-putations of predecessors show how the commitments at a particular time of an individual or a society to general beliefs about nature, man and science can make certain kinds of question appear cogent and give certain kinds of explanation their power to convince, and exclude others, because they establish, in anticipation of any particular re-search, the kind of world that is supposed to exist. They give satisfaction because the supposedly discoverable has been discoverer and they point to what to do in research. The comparative historical study of the intel-lectual and social commitments that may make certain kinds of scien-tific understanding, discovery or practical application intellectually and socially possible in one society, but difficult or impossible in another, has an immediate relevance for the diverse cultures brought into con-tact with the science of our contemporary world. Its matching relevance to our understanding of ourselves may be illustrated by trying to iden-tify some very general characteristics of our continuing rational tra-dition.
After the medieval West had received its first intellectual impetus from antiquity with the recovery of Euclidean geometry and of
stotelian logic and later of natural philosophy in the twelfth and thir-teenth centuries, the philosophical community of the universities may be credited with two major achievements : the grasp and elaboration of the construction of a deductive explanatory system, whether in logic, mathematics, cosmology or physiology; and the grasp and elaboration of logical precision in the use of evidence in deciding an argument, including decision by experiment. Characteristic of this intellectual inheritance, at least as it was received, was a geometrical or mathematical rationalism which is evident, for example, in Euclid's two fundamental treatises on optics and on music. * Each demonstrated a stable relation between perceiver and perceived by postulating in the one linear rays of vision and in the other motions propagated from a sounding body, from whose specified angles or speeds were demonstrated what speci-fic sizes and shapes must be seen or pitches and intervals heard. Reaching the West first mainly through Boethius and then through Arabic com-pendia (Euclid's texts became known only in the sixteenth century), these theories were made in the twelfth century part of philosophical programmes for the sciences which included also : «The science of engines (scientia ingeniis)... «which taught «the ways of contriving and finding out how natural bodies may be fitted together by some artifice according to number, so that the use we are looking for may
come from them».2
A programme is not an achievement but we are looking for mental attitudes, and it seems to me that we find already expressed in such words that urge towards rational analysis and ingenious contrivance for the mastery of nature, which was to be expressed in action by the artists, engineer-architects and musicians who from the fourteenth century were to give such an impressive practical demonstration of their theoretical control of visual space, material construction and instrumented sound. These groups introduced a new style of rationality into Western culture, adding to the logical control of argument and
1. Cf. CROMBIE, «The mechanistic hypothesis and the scientific study of vision*, Proceedings of the Royal Microscopical Society, ii (1967) 3 sqq., Mathematics, music and medical science*, Actes du XHe Congres international d'histoire des sciences 1968, i.B (Paris, 1971) 295 sqq., and for full discussion Styles of Scientific Thinking in the European Tradition (Gerald Duckworth, London, 1994).
2. DOMINICUS GUNDISSALINUS, De divisione philosophiae, ed. L. BA.UR (Beit-rage. .., iv. 2-3; Miinster, 1903) 122; cf. LYNN WHITE j r., «Medieval engineering and the sociology of knowledge*, Pacific Historical Review, xliv (1975) 1 sqq.
