Table Of ContentPHYSICS, COSMOLOGY AND ASTRONOMY, 1300-1700:
TENSION AND ACCOMMODATION
BOSTON STUDIES IN THE PHILOSOPHY OF SCIENCE
Editor
ROBERT S. COHEN, Boston University
Editorial Advisory Board
ADOLF GRONBAUM, University ofP ittsburgh
SYLVAN S. SCHWEBER, Brandeis University
JOHN J. STACHEL, Boston University
MARX W. WARTOFSKY, Baruch College of
the City University ofN ew York
VOLUME 126
PHYSICS, COSMOLOGY
AND ASTRONOMY,
1300-1700:
TENSION AND
ACCOMMODATION
Edited by
SABETAI UNGURU
Tel-Aviv University, Tel-A viv, Israel
Springer Science+Business Media, B.V.
Library of Congress Cataloging-in-Publication Data
Physlcs. cos.ology. and astrono.y. 1300-1700 : tenslon and
acco •• odatlon I edlted by Sabetal Unguru.
p. c.. (Boston studles In the phllosophy of sclence v.
128>
Papers fro. -a sprlng 1984 International workshop held. under the
ausplces of the Israel Acade.y of Sclences and Hu.anltles. by the
Institute for the Hlstory and Phllosophy of Sclence and Ideas of Tel
-Aviv Unlverslty In cooperat Ion wlth the Van Leer Jerusale.
Foundatlon"--Introd.
ISBN 978-94-010-5476-8 ISBN 978-94-011-3342-5 (eBook)
DOI 10.1007/978-94-011-3342-5
1. Sclence. Renalssance--Congresses. 2. Physlcs--Hlstory
-Congresses. 3. Astrono.y--Hlstory--Congresses. 4. Cos.ology-
-Hlstory. 1. Unguru. Sabetal. II. A~ade.yah ha-le·u.lt ha
-Ylsre'ellt le-.ada'l •. III. Unlverslţat Tel-Aviv, Institute for
the Hlstory and Phllosophy of Sclence and Ideas. IV. Mosad Van Llr
bl-Yerushalayl.. V. Serles.
0174.B87 voI, 128
[0125.2)
001 ' . O1 s--dc20
[509' ,4' 0902) 90-48538
Printed on acid-free paper
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© 1991 Springer Science+Business Media Dordrecht
Originally published by Kluwer Academic Publishers in 1991
Softcover reprint ofthe hardcover Ist edition 1991
No part of the material protected by this copyright notice may be reproduced or
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TABLE OF CONTENTS
SABETAI UNGURU / Introduction Vll
PART ONE
ANCIENT BACKGROUND
JOHN GLUCKER / Images of Plato in Late Antiquity 3
ABRAHAM WASSERSTEIN / Hunches that did not come off:
Some Problems in Greek Science 19
PART TWO
ISLAMIC AND JEWISH CONTRIBUTIONS
GAD FREUDENTHAL / (Al-)Chemical Foundations for Cosmo-
logical Ideas: Ibn Simi on the Geology of an Eternal World 47
BERNARD R. GOLDSTEIN / Levi ben Gerson: On Astronomy
and Physical Experiments 75
Y. TZVI LANGERMANN / The Astronomy of Rabbi Moses
Isserles 83
PART THREE
MEDIEVAL COSMOLOGY, NATURAL PHILOSOPHY, AND OPTICS
EDWARD GRANT / Celestial Incorruptibility in Medieval Cos-
mology 1200-1687 101
EDITH D. SYLLA / The Oxford Calculators and Mathematical
Physics: John Dumbleton's Summa Logicae et Philosophiae
Naturalis, Parts II and III 129
SABETAI UNGURU / Experiment in Medieval Optics 163
vi TABLE OF CONTENTS
PART FOUR
KEPLER: COSMOLOGY, ASTRONOMY, AND LIGHT
FRITZ KRAFFT / The New Celestial Physics of Johannes Kepler 185
DAVID c. LINDBERG / Kepler and the Incorporeality of Light 229
PART FIVE
SCIENCE, RELIGION, AND POLITICAL POWER
JOHN D. NORTH / One Truth or More? Demarcation in the
Universe of Discourse 253
MICHAEL SEGRE / Science at the Tuscan Court, 1642-1667 295
NOTES ON CONTRIBUTORS 309
NAME INDEX 313
SABETAIUNGURU
INTRODUCTION
Habent sua Jata colloquia. The present volume has its ongms in a
spring 1984 international workshop held, under the auspices of the
Israel Academy of Sciences and Humanities, by The Institute for the
History and Philosophy of Science and Ideas of Tel-Aviv University in
cooperation with The Van Leer Jerusalem Foundation.
It contains twelve of the twenty papers presented at the workshop by
the twenty-six participants. As Proceedings of conferences go, it is a
good representative of the genre, sharing in the main characteristics of
its ilk. It may even be one of the rare instances of a book of Proceed
ings whose descriptive title applies equally well to the workshop's topic
and to the interrelations between. the various papers it includes.
Tension and Accommodation are the key words.
Thus, while John Glucker's paper, 'Images of Plato in Late Antiqu
ity,' raises, by means of the Platonic example, the problem of interpreta
tion of ancient texts, suggesting the assignment of proper weight to the
creator of the tradition and not only to his many later interpreters in
assessing the proper relationship between originator and commentators,
Abraham Wasserstein's 'Hunches that did not come off: Some Prob
lems in Greek Science' illustrates the long-lived Whiggish tradition in
the history of science and mathematics. As those familiar with my work
will undoubtedly note, Wasserstein's position is far removed from my
stance on ancient Greek mathematics. I chose, therefore, to interfere
editorially as little as possible with its conclusions and approach,
appealing as they do to many workers in the field, and the paper stands
basically as given in its pristine allure. Another hunch that did not
come off, one might say.
Bernard Goldstein's paper on Levi ben Gerson shows us a man in
the fourteenth century who was not reluctant to use a hands-on. 'experi
mental' approach in the study of astronomy and who, in doing so,
preceded in his understanding and results some of Tycho Brahe's and
Johannes Kepler's achievements in the measurement of eclipses and on
pinhole images. Gad Freudenthal shows tellingIy the inherent elasticity
of theory in saving a cherished world view, specifically the eternity of
the world, that seemed to be inconsistent with the geological features of
the earth, as accepted by the theory. By postulating generative geologi-
s. Unguru (ed.), Physics, Cosmology and Astronomy, 1300-1700, pp. vii-viii.
© 1991 Kluwer Academic Publishers.
viii SABETAIUNGURU
cal processes compensating for erosion, and by drawing on alchemical
and chemical auxiliary concepts, Ibn Simi was able to save Aristotelian
natural philosophy from adverse criticism.
While Y. Tzvi Langermann deals with the astronomical views of
Rabbi Moses Isserles, a sixteenth-century famous legal scholar in
Cracow, during a period that witnessed a strengthening of rationalist
undercurrents in Jewish intellectual life, Edward Grant writes on
'Celestial Incorruptibility' and shows how a few significant cracks
developed within medieval cosmology, leading, eventually, to the aban
donment of the sacrosanct Aristotelian principle of celestial incorrupti
bility. Edith Sylla uses Parts II and III of Dumbleton's Summa logicae et
philosophiae naturalis to show how mathematics could also serve in the
hands of the Calculators in handmaiden status, at the pleasure of
physics, to deal with physical reality. It is this natural philosophical
tradition, striving to achieve an accurate knowledge of physical reality
by exploiting the fruitfulness of mathematics, rather than the logico
sophismatical tradition that makes the Calculators into an important
link between medieval qualitative physics and the new quantitative
physics of the seventeenth century.
'Experiment in Medieval Optics' discusses the role and limitations of
'experiment' in Witelo's Perspectiva, while Fritz Krafft's paper focuses
of the crucial role of physics in Kepler's new astronomy. David C.
Lindberg explores Kepler's ideas on the nature on light and establishes
their roots in the ancient and medieval optical tradition. Finally John D.
North tackles the problem of intellectual demarcation in connection
with a discussion of the issues of creation and eternity of the world,
showing the importance, profundity, subtlety, and intellectual pyrotech
nics of this medieval strategy of argument; and Michael Segre treats the
question of the relation of science and political power at the Tuscan
Court after Galileo's death.
These are, then, the contents of a volume that is meant to provide
the reader with a nontrivial sampling of the variety of interrelations
amongst physics, cosmology, and astronomy between, roughly, 1300
and 1700, of their tension, and eventual resolution in the new New
tonian science which supplanted medieval natural philosophy.
Tel-Aviv University
Tel-Aviv, Israel
PART ONE
Ancient Background
JOHN GLUCKER
IMAGES OF PLATO IN LATE ANTIQUITY
I have chosen my title quite deliberately, for reasons both subjective
and objective. Not 'The Image of Plato in Late Antiquity', since it is
now a commonplace that at no time has there been anything like one
and only kind of Platonism. Various interpretations of the dialogues
I
existed even among Plato's own pupils. Aristotle, his pupil for the best
part of twenty years, took the creation-myth of the Timaeus quite
literally as an event in time. Aristotle's friend Xenocrates - a pupil of
Plato 'from his youth', who even 'accompanied him on his trip to Sicily'
(Diog. Laert. IV, 6) and was his successor's successor as head of the
Academy - believed that the myth was merely an 'analysis for the sake
of examination' (what one could call geometrical construction), and that
the world of the Timaeus was eternal. So, for that matter, did
Xenocrates' pupil Crantor - but Crantor disagreed with him on the
meaning of the creation of the soul in the Timaeus.2 We shall soon see
that in late Antiquity there were at least two main 'images' of Plato
which, even though not mutually exclusive, were not quite the same -
and there were also relics, at least, of another image, rejected by the
upholders of both, but known to be of an ancient and honourable
ancestry.
Why, then, not 'The Images of Plato .. .' - apart from the awkward
English? Here my reasons are, as I have said, both objective and
SUbjective. Objective, since our evidence is, in the nature of the case,
partial and restricted. If it were not for one manuscript, written in A.D.
925 and miraculously preserved until it reached the library in Vienna,
we would have had no knowledge of the anonymous Prolegomena to
Platonic Philosophy,3 which is among other things (as we shall soon
see) one of our main sources for the lingering on of sceptic images of
Plato into late antiquity. And the one specimen of a Middle Platonic
commentary on a dialogue which we possess has been found in a
papyrus roll.4 For all we know, there may have been some Stoic or -
more probably - sceptic treatises on Plato still extant in late antiquity.s
But they have not reached us.
My subjective reasons are even simpler. I have neither the equipment
nor the preparation for offering a Platonic counterpart to Professor
Moreaux's monumental Der Aristotelismus bei den Griechen (Berlin:
S. Unguru (ed.), Physics, Cosmology and Astronomy, 1300-1700, pp. 3-18.
© 1991 Kluwer Academic Publishers.
