Reason, Experiment, and Mysticism in the Scientific Revolution

163 Pages·1975·8.4 MB·English

by  Maria Luisa Righini Bonelli, William R. Shea

R e a so n , E ip c r im e n t,
anD M y s r td s m
IN THE SCIENTIFIC
REVOLUTION
M. L. Righini Bonelli
and
William R. Shea
Editors
ILLUSTRATED
Sh P
SCIENCE HISTORY PUBLICATIONS
NEW YORK • 1975
CONTENTS
First published in the United States by
SCIENCE HISTORY PUBLICATIONS
a division of Introduction: Trends in the Interpretation
Neale Watson Academic Publications, Inc.
of Seventeenth Century Science
156 Fifth Avenue, New York 10010
WILLIAM R. SHEA 1
The Chemical Debates of the Seventeenth Century: the
Reaction to Robert Fludd and Jean Baptiste van Helmont
ALLEN G. DEBUS 19
Alchemy in the Seventeenth Century: The European and
Italian Scene
CESARE VASOLI 49
New Light on Galileo’s Lunar Observations
GUGLIELMO RIGHINI 59
Dissertatio cum Professore Righini et Sidereo Nuncio
OWEN GINGERICH 77
©Science History Publications 1975
First Edition 1975 Terrestrial Interpretations of Lunar Spots
(CIP Data on final page)
Designed and manufactured in the U.S.A, WILLY HARTNER 89
Marcello Malpighi and the Founding of Anatomical
Publisher’s Note No effort has been made to superimpose a rigid
Microscopy
uniformity of style or syntax. The authors’ wishes have been
followed wherever possible. Controversial matters have been re­ LUIGI BELLONI 95
solved with the assistance of the editors.
If the publishers have unwittingly infringed the copyright in any Malpighi, Descartes and the Epistemological Problems
illustration reproduced, they will gladly pay an appropriate fee on of latromechanism
being satisfied as to the owner’s title.
FRANCOIS DUCHESNEAU 111
Galileo’s New Science of Motion
STILLMAN DRAKE 131
Introduction:
• The Sources of Galileo’s Early
Natural Philosophy Trends in the Interpretation
of Seventeenth Century Science
A. C. CROMBIE 157
Mathematics and Galileo’s Inclined Plane Experiment
WILLIAM R. SHEA
PIERRE COST ABEL 177
The Role of Alchemy in Newton’s Career The interplay and the natural influence of theory and ex­
periment in the rise of the experimental method has often
RICHARD WESTFALL 189
been discussed. What is novel, both in the history and the
Newton, a Sceptical Alchemist? philosophy of science, is the growing interest in mysticism, a
catch-all word used to characterize various forms of her­
PAOLO CASINI 233
meticism, alchemy and Renaissance naturalism. Among
these currents, which until recently could be described as
Newton’s Voyage in the Strange Seas of Alchemy
“non-modern”, hermeticism or the belief that there existed
MARIE BOAS HALL 239
a secret tradition of knowledge that gave a truer insight into
the basic forces of the universe has enjoyed particular
Hermeticism, Rationality and the Scientific Revolution
favour. Less studied, but equally important, is the group of
PAOLO ROSSI 247 Paracelsian physicians and philosophers whose works are
analysed by Allen G. Debus in this volume. But in both
Magic, Metaphysics and Mysticism in the cases, we stand very much in need of an appraisal of those
Scientific Revolution
once famous men whose writings have sunk below the hori­
A. RUPERT HALL 275 zon of post-Newtonian science.
Mysticism, which looms so large today, was excluded
The Mathematical Revolution of the Seventeenth Century from the history of science and the history of medicine on
the grounds that it was irrelevant to the mainstream of sci­
RENE TATON 283
entific thought. Positivist historians of science directed their
attention to that segment of the past that could be related
with present concerns and contemporary methods. But as
historians of science became more conscious of the need of
acquiring a feeling for the contemporary resonance of ideas
and concepts, they were led to see that events as experi­
enced by actual men can only be understood by becoming
involved in their general outlook. This meant that his­
torians of science had to busy themselves with false starts as
well as successful arrivals. The distinction between wrong
vi
INTRODUCTION
WILLIAM R. SHEA
question is not whether men wished to be rational or irra­
and right steps, however, was assumed to be clear and to
tional but whether the hermetic and mystical traditions had,
rest on the bedrock of scientific achievernents. In recent
in the seventeenth century, as good credentials of rational­
years, doubt has been cast on the overall achievement of
ity (as it was then understood) as the mechanical
modern science and, consequently, the clarity of the distinc­
philosophy. Debus and Westfall address themselves to this
tion has been blurred. This had made it easier for historians
question with exemplary open-mindedness. This is no easy
of science to take a further step in reappraising the his­
task because losers are always wrong, and we see ourselves
toriography of science and |;o raise the crucial question: Are
as the heirs of the victorious mechanical philosophers. In
“mystical” traditions and “modern” elements in the Scien­
retrospect, Fludd and van Helmont were in the dark about
tific Revolution antagonistic or, paradoxically, complemen­
the best strategy to promote human understanding, but for
tary extremes?
their contemporaries, Mersenne, Gassendi and Kepler, they
It is usually said that two dominant strands made up
were dangerous rivals in the quest for the true philosophy
the warp and woof of the new science. One expressed itself
of nature. It is hard for us to imagine that alchemy, which is
in the mechanical philosophy and had its roots in the
now relegated to the lunatic fringe, was at one time a seri­
atomism of the ancient world, the other was concerned with
ous contender for the throne of reason. But until the cor­
the exact mathematical description of phenomena and traced
rect route to scientific knowledge had been discovered (in
its origins to the Pythagorean tradition. This now seems an
Bacon’s phrase “not by arguing but by trying”) it was an
incomplete picture, for it is just as likely that two other an­
open question what kind of world men found themselves
cient traditions contributed to shaping what we have come
inhabiting and radically different answers could claim a
to know and to rely on as the experimental method. These
reasonable man’s consideration.
are the Aristotelian philosophy with its logical rigour and its
Debus makes a major contribution towards a reassess­
insistence on a realistic interpretation of nature and the
ment of the hermetic and mystical background to much of
hermetic tradition with its reliance on experiment, its ap­
seventeenth century science. As with so many other things,
preciation of the crafts and its utilitarian outlook on science.
it is largely a matter of perspective. When we look at the
We sometimes forget that latter-day opponents of Aristotle
Paracelsian iatrochemists, who combined the study of
often retained more of his views than they would have been
medicine and chemistry, not, superficially, as self-deluded
fond of admitting, and we have only too frequently read the
mystics, or, anachronistically, as chemists who failed to
history of mysticism in the works of those who condemned
bring about a chemical revolution, but as the Chemical
it. Until we learn to see Paracelsus, Bruno, Campanella and
Philosophers they considered themselves, their programme
their kindred spirits as they saw themselves, we shall con­
becomes both more interesting and more reasonable. We
tinue to be trapped in the prejudices of their adversaries.
begin to see why their appeal was so broad and why their
This new research programme, so brilliantly illustrated
ideas were discussed by people interested in religious and
in the articles by Debus and Westfall is, unfortunately, in
educational reform as well as by physicians and philosophers.
danger of being jeopardized by those who present the issue
For the Chemical Philosophers, the unity and harmony
as one of rational-vs-irrational elements in the development
of the universe was an obvious consequence of creation by a
of modern science. This is profoundly misleading for the
WILLIAM R. SHEA INTRODUCTION
wise and benevolent God. This belief was shared by the vast against the mechanical philosophy, not because it was a new
majority of seventeenth century thinkers who instinctively form of knowledge, but because it appeared to be a reduc-
shunned the materialistic implications of the mechani­ tionism founded on the purely speculative premise that ev­
cal philosophy. They could not fail to attend to a new erything in nature can be explained on the analogy of a
philosophy that professed to achieve better scientific results clock.
with principles that conformed to Christian precepts rather Debus argues that van Helmonfs chemical philosophy
than those of the “Pagan Aristotle”. But this religious tone presented itself to the rational enquiring mind of the mid (
was not generally confessional, and many radicals welcomed seventeenth century as a genuine alternative to Cartesian |
the prospect of bypassing the authority of the established mechanism and that it reacted in a complicated way on this ?
churches to pursue an independent study of the two God- philosophy to bring about a more experimental approach to
given books: the Bible and the Created Book of Nature. chemistry. This claim, which would have sounded prepos­
God created all things that they may be perfect and the terous twenty years ago, must now be taken as one of the
r''
iatrochemist considered it a duty as well as a privilege to be most serious reassessments of the development of the scien­
called upon to assist the natural process towards perfection tific method. We are now apprised that the mechanicaf
by removing the pure from the impure and allowing the philosophy was often a thin veneer to cover a basically or­
seeds of things to attain their ends. jBaser metals could be ganic vision of the universe. In the case of Kenelm Digby,
hastened toward perfection and ill-tempered constitutions for instance, it was a thin sheet of ice that barely concealed
could be amended with the aid of chemistry. The spagiric the objectionable features of a philosophy that he was un­
art, as after Paracelsus alchemy was defined, worked for the able to forsake.
well-being of nature whether vegetable, mineral or animal. The shortcomings of the mechanical philosophy were
It was a practical art and alchemists were not afraid of particularly glaring in medicine and chemistry. The new
working with their own hands. They ridiculed the pedantry conception of nature proclaimed the need of purging the
and logical exercises of the Schoolmen who cared for no­ body of natural philosophy of the occult and looked for the
thing but the words of Galen and Aristotle. The philosophy mechanical reality behind every phenomenon. Yet it of­
they appealed to was neither the qualitative physics of Aris­ fered no way of discriminating between competing invisi­
totle nor the mathematical harmonies of the Neo-Platonists ble mechanisms and the unity of chemistry dissolved into as
but Renaissance naturalism in which macrocosm-microcosm many theories as there were philosophers to imagine various
analogies provided clues and, in some cases such as Fludd, hidden springs of matter. More fundamentally, still, the
even evidence for the truth of general theories. This or-? Cartesian programme broke down in its attempt to explain
ganic vision of the universe and the insistence on experi­ life as a mere appearance, a species of occult quality.
ments made them scornful of mathematical rigour. When With the advantage of hindsight, we can see that the
Fludd accused Kepler of belonging to the “vulgar crowd mechanical philosophy had to be given a broader base to
that pursues quantitative shadows”, he was voicing the per­ include the chemical and biological data that it initially pre­
suasion, common among alchemists, that mathematical cluded itself from understanding. We are not faced with a N
reasoning, however coherent, rests on abstract assumptions simple clash between two completely contrasting viewpoints*^
that are not borne out in experience. They inveighed but with a complex interaction between two systems in-S
WILLIAM R. SHEA INTRODUCTION
fluencing each other and eventually giving rise to a new and Now that we know how deeply fascinated Newton was
richer method of scientific investigation. by alchemical treatises and what store he put in them, we
If the contribution of van Helmont’s iatrochemistry to shall have to reconsider, as Westfall suggests, the route that
the development of modern chemistry seems assured, it is led to the Principia themselves. In the standard accounts of
more difficult to assess the importance of hermeticism in the history of science, the law of universal gravitation is pre­
the genesis of Newtonian physics. In a critical description sented as the outcome of a fruitful suggestion by Robert
and chronological ordering of Newton’s alchemical writings, Hooke and an opportune question by Edmund Halley. It is
R. S. Westfall offers striking evidence that Newton’s interest difficult to see how the “noble art” could have affected the
in alchemy continued unabated between 1670 and 1696, the course of rational mechanics, but this may be simply be­
year he left Cambridge to become Warden of the Mint. The cause we are not trained to look for likely evidence. The
\ /'■
bulk of his notes is impressive (well over half a million first step in the right direction is perhaps to don the think­
words), but more revealing still is the fact that Newton at­ ing cap of the Cartesians and to learn to fear, with them,
tempted to write alchemical treatises himself, and that al­ that Mr. Newton was introducing an occult quality under
chemy was his only abiding passion. He devoted merely two the guise of attraction. The next step is to ask whether
years, 1664-1665, to mathematics and from that time on Newton’s disparagement of occult qualities in the famous
would only turn to it when solicited. He concerned himself Query 31 of the Opticks is more political than real, and
with optics for a brief period around 1670 but he never whether it could have stemmed from a desire to repel the
returned seriously to it again. Mechanics and dynamics held charge of obscurantism rather than from the fear of becom­
his attention for a short while in the 1660s and then only in ing an obscurantist.
the two and a half years that produced the Principia. It is Paolo Casini and Marie Boas Hall agree that Newton’s
hard to escape the conclusion that this great work, which we radical revision of the prevailing mechanical philosophy of
see as the culmination of Newton’s career, may have seemed nature by embracing the notion of action at a distance no
to him as an interruption or no more than a partial fulfil­ longer seems unconnected with his alchemical activities.
ment of a much more grandiose plan. They regard this view as promising but they urge that it be
Newton was convinced that there was an underlying followed with caution. Once hermetic themes have been
unity to alchemy and that a comprehension of the alchemi­ unearthed, there is a real danger of seeing them every­
cal “work” could be achieved both by comparing the various where. If we are to make any headway in our appreciation
symbols they used and by making experiments. Although of the influence of mysticism, we must be willing to indi­
the records of Newton’s chemical experiments are seldom viduate and specify its various manifestations. For instance,
couched in the imagery familiar to alchemical writers. West- the pervasive “book of nature” analogy is in itself highly
fall believes they were performed against the background of ambiguous. While it was at the tip of everyone’s pen it did
two fundamental tenets of hermeticism: first, the belief that not carry the same meaning for every writer. Galileo and
generation by male and female is a universal process at all Kepler believed that God wrote the book of nature in
levels of nature, and, second, the need to purge and mathematical characters but Bruno and Campanella inter­
cleanse in order that the spiritual seeds of things may reach preted it as the work of the Arch-Magician. It is true that
maturity. mathematics can work wonders and that magicians juggle
6
INTRODUCTION
WILLIAM R. SHEA
nary but he kept his ideas under the control of mathemati­
with numbers but the methodological programmes of the
cal reasoning and physical experience. The student of Ke­
two schools were profoundly at variance. The “book of na­
pler should feel the intensity of his vision on his own pulse
ture” metaphor used by all parties serves to conceal these
but also be prepared for a long process of thought to un­
differences. The following famous poem by Campanella
derstand the sources of his vision and to be able to weigh its
could have been written by Galileo or Kepler but it would
numerous elements. These must be studied in detail if their
then have carried a different message.
contribution to the whole is to be understood. Yet it would
II mondo e il libro dove il Senno eterno be wrong to assume that an exhaustive study of the compo­
scrisse i propri concetti, e vivo tempio
nent parts of'his system is sufficient in itself. For instance,
dove, pingendo i gesti e 7 proprio esempio,
although Copernicus spoke of the sun as the “gubernator” of
di statue vive orno I’imo e 7 superno;
the planets, he did so only in the sense of one who is at the
perch’ogni spirito qui I’arte e 7 governo
helm, not as the motor of the planetary revolutions. The
leggere e contemplar, per non farsi empio,
first to suggest that the sun, because of its central position,
debba, e dir possa: “lo I’universo adempio,
is the source of the motion of the planets, was Rheticus in
Dio contemplando a tutte cose interno/’
his Narratio Prima. But this idea was not taken up until Ke­
Ma noi, strette a' libri e tempii morti,
pler saw the necessity of a physical explanation of the re­
copiati dal vivo con piu errori,
volutions of the planets. The concept that the sun is the
gli anteponghiamo a magistero tale.
“gubernator” of the planets is Stoic in origin, and Kepler may
O pene, del fallir fatene accorti,
be considered as having extended and mathematized this
liti, ignoranze, fatiche e dolori:
notion. The terminology he uses, “anima movens”, indicates
deh torniamo, per Dio, all’origihale!
the source of his natural philosophy but it would be errone­
ous to reduce it to a modified form of an organic vision of
(The world is the book where eternal Wisdom wrote its own
the world. Blinkered accuracies about Kepler’s vocabulary
ideas, and the living temple where, depicting its own acts
and likeness, it decorated the height and depth with liv­ will tell us very little about his conception of nature.
Faced with a task of this kind it is tempting to take a
ing statues; so that every spirit to guard against profanity,
direct line; to project into Kepler a set of opinions that can
should read and contemplate here art and government, and
each should say; “I fill the universe, seeing God in all be seen to fit some area of his work and then view every­
things.” thing against them. This was done with literary panache by
But we, souls bound to books and dead temples, copied Koestler in The Sleepwalkers and the vividness of his descrip­
tion masks the one-sidedness of his interpretation. By re­
with many mistakes from the living, place these things be­
ducing Kepler to a psychiatric case, Koestler has secured for
fore such instructions. O ills, quarrels, ignorance, labours,
pains, make us aware of our falling away; o, let us, in God’s him a twentieth century notoriety that he would not have
name, return to the original! [Trans, by George Kay, The had otherwise. Newton has yet to be made fashionable in
this way and it is interesting that none of the contributors to
Penguin Book of Italian Verse, pp. 203- 204]).
Kepler offers a particularly fascinating case study in the this volume has chosen to make much of Frank Manuel’s
suggestion that Newton be, in a sense, psychoanalyzed.
pitfalls of historical interpretation. He was a mystical visio­
9
INTRODUCTION
WILLIAM R. SHEA
invisible to the naked eye though in principle observable did
They have preferred to tackle a different set of questions
not enter into his research programme.
and to ponder the problem of Newton’s intentions. Was
Newton reading the hermetic literature to find evidence or The abstract nature of the models used to understand
nature and their extension to the realm of man (illustrated
merely phenomena about the physical world? It is along these
lines that a fruitful debate is now open. and discussed in the articles by Belloni and Duchesneau)
can be ascribed to the mechanical philosophy. So can the
Paolo Rossi, whose Francis Bacon, From Magic to Science
was a pioneering work in the rediscovery of the “mystical” distinction between primary and secondary qualities, the
roots of the Scientific Revolution, is concerned lest, in our stress on the “subjectivity” of sensory experience and the
concentration on the roots, we forget the characteristic fea­ “objectivity” of mechanical laws, as well as the idea of God
as a watchmaker. But many of the characteristic features of
tures of the full-grown tree. The seventeenth century was a -
distinctive age in that it witnessed an enormous expansion the new scientific spirit owe at least as much to the “mysti­
cal” traditions. The new appreciation of the crafts and the
of knowledge. Overseas expeditions revealed the existence
of new plants and new animals. Intensified anatomical re­ need for experiment were long recognized by iatrochemists.
search uncovered new information about what had been The same can be said of the ideal of scientific co-operation
and the notion of progress as growth of mankind. The in­
considered well known, the circulation of the blood was dis­
covered, the theory of spontaneous generation was refuted, finity of the universe and the rise of cultural relativism were
and new evidence about the age of the earth ushered in a mainly discussed by hermeticists such as Bruno and Cam-
new way of thinking about Adam. New instruments opened panella. Even what we refer to as Baconian utilitarianism or
up new fields of investigation. The telescope revolutionized the pursuit of science for the relief of man’s estate was a
the study of the heavens, the microscope disclosed new frequent theme among the exponents of the Ghemical
realms of life, the airpump made a virtual vacuum possible, Philosophy. To speak of this idea as typically Baconian is
the barometer and the thermometer brought atmospheric merely to vouch for the literary gifts which have continued
pressure within the bounds of measurement, and the first to make him read when his less fortunate contemporaries
precision clock enabled man to speak of time in a new idiom. have sunk into oblivion.
But the Scientific Revolution was primarily a matter not Equally new is the relationship of “art” to “nature” and
of new facts, but of new ways of looking at old facts. Galileo the ideal of knowledge as “construction”. The nominalistic
may have been the first to turn the telescope”to the sklSISit notion that we can only know what we can make runs
the heliocentric theory he embraced had been elaborated through the works of Mersenne, Gassendi and Hobbes.
without its aid and Kepler had worked out the correct path This view precludes any “deep” knowledge of nature, but it
of Mars before he heard" of its invention. The microscope is a philosophical stance that is not shared by the main arti­
was not used systematically before Malpighi. Harvey, whose sans of the Scientific Revolution who were thoroughgoing
work is largely posterior to the invention of this instrument realists. Mersenne and Gassendi argued in innumerable
failed to make use of it. It is not that Harvey rejected the folios that if we can only know what we can construct, then
microscope as technically inadequate for he occasionally human understanding is precious little since God alone can
used lenses of low magnification. It is simply a problem of create nature. Galileo, Kepler, and Descartes, on the con­
method; the necessity of considering the existence of entities trary, insisted that God was a geometrician in his creative
11
10
WILLIAM R. SHEA INTRODUCTION
labours and that mathematics laid bare the foundations of method was shown by A. C. Crombie in his Robert Grosseteste
the cosmic structure. In his Mysterium Cosmographicum, Ke­ and the Origins of Experimental Science to have been discussed
pler is conscious of speaking paradoxically when he says by the Bishop of Lincoln and his disciples in the Middle
that God created “nature” according to the “art” of an ar- Ages. But as Crombie himself perceptively notes, one
^lTitcctT”It is tempting to suggest that those for whom the should not equate philosophical discussions of method with
new philosophy (however superior to the old) gave no real actual practice of scientists, a word of caution, let it be said,
insight into the recesses of nature were men who had once that is not always heeded by those who are mainly in­
shared the Aristotelian persuasion that true understanding terested in logical and epistemological theories about sci­
is abstraction of “essences” and “substantial forms”. When ence.
they rejected these “forms” as a scientific delusion, they Empirical investigation, in the sense of the formulation
proceeded, with the enthusiasm of neophytes, to proclaim of hypotheses on the basis of empirical data stated with suf­
the bankruptcy of human knowledge itself. But for those ficient rigour to allow the hypotheses to be stringently
men, like Galileo and Kepler, who were familiar with the tested, was not widespread before the seventeenth century.
tenets of the old school but never belonged to it, matters This method stands in constrast not so much with the
were different. When they came to see that “essential Chemical'as with the Aristotelian philosophy. However at
forms” were mere abstract notions, they asserted that the odds the new scientists may have been on points of
true world was composed of atoms that move according to philosophy, they rose to a man when it came to pass judg­
intelligible mathematical laws. Mersenne and Gassendi ment on the method of the old physics which they consi­
were, in a sense, reluctant converts to a new way of viewing dered a method of exposition not a method of discovery or
nature; Galileo and Kepler travelled farther along the road proof.
that led away from Aristotelianism. This is not to affirm We can hardly overestimate the importance of the ideas
that they were completely divorced from the past but simply that a scientist brings to his scientific work especially those
that it would be erroneous to read their works as if they which concern what he is looking for and what constitutes
were merely refurbishing old ideas. evidence for a theory. Now what counted as evidence for
For when all is said and done there was a radical the old physics (which borrowed its paradigm of scientific
change in the seventeenth century. The Scientific Revolu­ reasoning from the Posterior Analytics) seemed to the new
tion consecrated a new method that was slowly to transform generation to be completely at variance with what ought to
a civilization organized around Christianity into one centred be treated as evidence.
on science. This way of thinking is usually described by the I Aristotle’s ideas about what it means to know — to know
short-hand term of the experimental method, meaning the active scientifically — were so diffuse that they must be recalled
questioning of nature under conditions defined by the here, however briefly, if the novelty of the new experimen­
experimenter rather than the mere observation of the tal method is to be appreciated.
phenomena that spontaneously present themselves. Of Aristotle’s views on scientific knowledge rest on a cos­
course, there is no one rigid experimental method that is mological assumption about the nature of the universe and
uniformly applied throughout all the sciences, and even the an epistemological assumption about the nature of the
outline of what is now called the hypothetico-deductive human mind. The first assumption is that there exists a
12 13
WILLIAM R. SHEA INTRODUCTION
world of essences arranged in hierarchical structures that Sciences, such as astronomy, that use mathematics as
can be laid out logically. This world is basically of a teleolog­ their syntax, were not, strictly speaking, physical sciences.
ical sort and essences are disclosed by their finalities. The They were said to move on a level of abstraction that did
second assumption is that the human mind is gifted with not consider physical entities in their entirety. Such an ab­
the quality of insight which enables it to grasp essences, to straction gave no direct insight into the nature of things and
“see” the universal in the particular. This power of abstrac­ remained hypothetical. Epicycles and the like were calculat­
tion, as it is sometimes called, allows man to perceive the ing devices not real explanations of the motion of the
premises of natural science as necessary truths. planets.
From these two general assumptions there follows a Since nature was to be discovered not by asking what a
method of knowing. Since concepts are derived im­ thing would do in every conceivable context, but what it
mediately from ordinary experience, what characterizes a does in its natural context, it comes as no surprise that ex­
body is its habitual mode of behaviour, some “natural mo­ periment is not even discussed in the Posterior Analytics. The
tion” which expresses its “form”. Earth, for instance, natur­ artificial simplification of the natural context would have
ally moves downwards because in its normal context it will seemed wrong-headed.
either be at rest or falling towards the centre of the world. Modern science, on the contrary, assumes that it is by
Everyday language is sufficient to state the nature of the imposing on nature a set of artificial conditions dictated by
elements which are defined by the sensory qualities of hot a precise question that nature will reveal its secrets. Eor in­
and cold, dry and moist. “Essences” once named are located stance, Torricelli would never have filled a glass tube with
in a network of concepts that are related through mutual mercury and erected it on a dish if he had not had a specific
definitions. There is no need for technical concepts such as design in mind. Nature only speaks in the language in
those of mathematics and there is no question of a quantita­ which it is interrogated.
tive structuring of experience. Quantity is irrelevant be­ The development of this modern method of empirical
cause it can only tell how much of a substance we have, not investigation with its twin aspects of idealization and con­
what kind. trivance was a slow process. However hostile to the Aristo­
In this perspective, science was basically a descriptive telian establishment, Galileo, for one, remained profoundly
enterprise. Aristotle objected to Plato’s assertion in the influenced by the model of scientific explanation in the
Timaeus that the world is composed of atoms of certain Posterior Analytics and his lifelong passion was to show that
shapes because the warrant he offered came not from ob­ the Copernican system could be demonstrated with all the
servation but from pure geometry. Neither could Aristotle rigour demanded by the Aristotelian canons. In his impor­
entertain the idea that a body of scientific doctrine was a tant essay in this volume, A. C. Crombie conclusively estab­
theory in the modern sense of a logical and mathematical lishes that Galileo was well read in the best scholastic litera­
network of laws that have to be anchored in the empirical ture of his day and that his early writings owe much to
data available. His teleological bias meant that nature was three Jesuit professors of the Gollegio Romano. Crombie
considered as a process and this turned speculation away points out that Galileo’s running argument against Aristotle
from questions of structure and mechanism towards ques­ can obscure the fact that he never wavered in his Aris­
tions of function and development. totelian belief that there is a literally and uniquely true
14 15