Schmitt C.B. (ed.) The Cambridge History of Renaissance Philosophy
Подождите немного. Документ загружается.
Traditional
natural philosophy
207
heavens and speculated
that
the
earth
might be in motion also, undergoing
slight
translational shifts as it adjusted its centre
of
gravity
to be in the centre
of
the universe. He recognised
that
astronomical phenomena could be saved
equally
well
by having the
earth
rotate
daily on its axis as by having the
heavens do likewise, but regarded this as insufficient basis for rejecting
scriptural teaching on the stability of the earth. Oresme further adopted
Buridan's notion of impetus to explain the acceleration of heavy bodies
during
fall,
and possibly saw
that
velocity of
fall
would increase directly
with
time of
fall,
without offering any distance calculations to substantiate
this result. Oresme's influence on subsequent investigators is difficult to
ascertain, since his writings remained largely in manuscript, but they
illustrate the degree of mathematical sophistication already reached in the
mid fourteenth century.
16
Copernicus, on the other hand, writing almost
two
centuries later, was to have a profound
effect
on the development of
astronomical science. A calendar-maker who had studied in Italy, this
Polish
canon worked out a complete heliocentric alternative to the
Ptolemaic system of the world, publishing it in his De
revolutionibus
orbium
caelestium
of
1543.
Although Osiander in an unsigned preface to the volume
proposed it as a
pure
mathematical hypothesis, Copernicus regarded his
system
as physically
true,
and inspired others, such as Kepler and
Galileo,
to
become
advocates of the 'new astronomy' and achieve its general
acceptance by the end of the seventeenth century.
17
The
observational component of methodological change was enhanced
from a variety
of
directions, ranging from humanist critiques
of
the
natural
history of Pliny, through studies in medicine and surgery aimed at
improving (and correcting) the teachings of Hippocrates and Galen, to a
renewed emphasis on the empirical base for the Aristotelian corpus. This
inevitably
augmented the observational content of
natural
philosophy and
even
led to the use of experimental procedures, to be treated more
fully
below.
Behind this development was a general conviction
that
the human
mind can safely reason from effects or
symptomata
to their hidden causes, and
then
use such causes, newly discovered, to
structure
scientific explanations
of
the phenomena
that
had been observed. Although generally endorsed
and explained previously by figures such as Albertus Magnus and Thomas
16.
Recent
editions
of
Oresme's
writings
make
his
thought
accessible
to
scholars;
see
particularly
those
of 1966,
1968a,
1968b
and 1971.
17.
The
fifth
centenary
of the
birth
of
Copernicus
(Dictionary of Scientific Biography
1970-80,
in, pp.
401-11) in 1973
made
a
wealth
of
information
available
concerning
him; see the
collections
of
essays
in Nature of Scientific Discovery 1975; Science and Society 1975; Copemican Achievement 1975;
also
Gingerich
1973, 1983.
Cambridge Histories Online © Cambridge University Press, 2008
208
Natural philosophy
Aquinas,
this type of a
posteriori
reasoning reached perfection at the
University of Padua towards the end of the sixteenth century. The
groundwork was laid
there
earlier by Pietro d'Abano in medical contexts
and then, in the fifteenth century, by Paul
of
Venice
and Gaetano da Thiene.
The
latter,
together with Ugo Benzi da Siena and Jacopo da Forli,
combined an interest in 'calculatory' techniques with a search for causes by
resolving
effects to them, and
then
composing causes with these effects to
achieve
propter
quid
explanations. The culmination of this movement is
found in the writings of Agostino
Nifo
and Jacopo Zabarella. Zabarella
worked extensively in logic and
natural
philosophy, and is particularly
noteworthy for his insistence on observation and empirical grounding
when studying
nature,
not only in practice but in the
logical
justification of
his investigative procedures.
18
Technological
improvements, together with the perfecting of the
printing press and its contribution to graphical representation and wide
distribution of results, also enhanced
natural
philosophy, though in a less
direct way. Experimentation would not have been possible without skill in
instrument
making, and artisans and craftsmen could only work with the
materials industry made available to them. Architects and engineers
rediscovered the works of Vitruvius, and in the building of domes and
elaborate edifices had to make use of, and so perfect, their knowledge of
mechanical principles. Leonardo da
Vinci
is usually singled out as an
important innovator in this regard.
19
His
Notebooks,
it is
true,
contain
ingenious sketches and mechanical designs in advance of his time, but they
were never circulated and so exerted little influence on his contemporaries.
More significant were Francesco di Giorgio (Martini), some of whose en-
gineering designs were appropriated by Leonardo; Georg Bauer
(Agricola),
whose De re
metallica
gave an excellent
view
of advanced mining tech-
niques; and
Vanoccio
Biringuccio, whose De la
pirotechnia
did the same
for
metallurgical processes.
20
Mention should also be made of Andreas
Vesalius'
Defabrica
corporis
humani
of 1543, whose graphic illustrations of
the organs of the human body did more to promote medical knowledge in
the mid sixteenth century
than
any other work of the time.
21
18.
There
is an
extensive
literature
on
these
Paduan
Aristotelians;
see Aristotelismo veneto 1983 for a
recent
collection
of
essays,
as
well
as the
earlier
studies
of
Cassirer
1911;
Randall
1940, 1961; N. W.
Gilbert
i960,
1963; W. F.
Edwards
i960,
1967;
Poppi
1970a,
1972a;
and
Wallace
1972-, 1, pp.
117-55.
19.
Dictionary of Scientific Biography
1970-80,
vm, pp.
192-245
('Leonardo
da
Vinci').
20. Ibid., ix, pp. 146-8
('Martini');
1, 77-9
('Agricola');
11, pp. 142-3
('Biringuccio').
21.
Ibid., xiv, pp. 3-12
('Vesalius');
the
illustrations
of the Defabrica
have
been
reissued
in
facsimile,
with
descriptions
of
each
plate,
in
Vesalius
1950.
Cambridge Histories Online © Cambridge University Press, 2008
Traditional natural philosophy
209
As
the Middle
Ages
gave way to the Renaissance there were finally
changes in dialectical and disputational modes
that
are reflected in the
ways
natural philosophy and medicine were treated. The medieval
disputatio,
with
its presentation of arguments pro and con, proof of these and replies to
objections,
continued to influence the way the
scientiae
naturales
were taught
over
a considerable period. Since Aristotle was the main authority,
commentaries on his writings were an important vehicle, but these were
supplemented by 'questionaries'
that
treated disputed points and school
positions in exhaustive detail.
22
This scholastic mode influenced medical
writing as
well
as
that
on
nature
throughout the fourteenth and fifteenth
centuries.
23
Under humanist influences, however, the later Renaissance saw
a reaction against scholastic method and the arid treatises it tended to
produce. Particularly in Italian universities a more discursive and literary
style
was adopted, with classical allusions and more attention to philology
and the Greek text. The works of
Nifo
and Zabarella, to say nothing of
Boccadifero,
Buonamici, Cremonini, Mazzoni, Pendasio and Porzio, are
very
different from those of Paul of
Venice
or Blasius of Parma, and
that
simply
on the basis of style of argument and presentation of results.
24
NATURAL
PHILOSOPHY
IN THE
STRUCTURE
OF
KNOWLEDGE
Notwithstanding these different emphases, the content of natural philos-
ophy remained much the same throughout the centuries under discussion,
when
it had a much broader meaning
than
it has in the present day.
Philosophy itself then extended to all
that
is knowable by human reason,
and a major
part
of
its concern was with the world
of
nature. To
give
some
idea of the extent of both disciplines in the Renaissance curriculum, a
representative division of their respective structures is given here. Some
authors departed considerably from the
following,
which is based on
22.
Representative
works
are the
textbooks
on
natural
philosophy
produced
at
Paris
in the
early
sixteenth
century,
especially
those
of
George
of
Brussels,
Petrus
Crockaert,
Juan
de Celaya and
Luis
Coronel;
see Garcia
Villoslada
1938 and
Elie
1950-1
for
listings
and
surveys
of
their
works.
These
had a
pronounced
influence
in
Spain,
particularly
at
Salamanca,
where
the
commentary
and
'questionary'
on the Physics by
Domingo
de
Soto
enjoyed
great
popularity.
One of the
most
synthetic
treatments
of the
materials
in the
Physics,
juxtaposing
the
teachings
of the
various
schools,
is the Physica
published
at
Valencia
by
Diego
Mas in 1599, to be
discussed
below.
See
also
Schmitt
in
this
volume,
pp.
792-804
below.
23.
Bylebyl
1979 and
forthcoming.
24.
Most
of
these
works
are
listed
in Lohr:
Boccadifero
(Buccaferrea),
1974b, pp.
281-6;
Buonamici,
1974b, p. 272;
Cremonini,
1975, pp.
728-39;
Nifo,
1979, pp.
532-9; Pendasio,
1979, pp.
556-62;
Porzio,
1980, pp.
667-70;
and J.
Zabarella,
1982, pp.
233-42.
Cambridge Histories Online © Cambridge University Press, 2008
2IO
Natural philosophy
Francisais Toletus,
but his
classification
has the
merit
of
epitomising
the
Greek
and
Latin textual traditions
as
well
as the
scholastic revivals
in
Italy
and
the
Iberian peninsula.
25
The
function
of
philosophy,
for
Toletus,
is to
dispel man's ignorance
in
three areas:
in his
contemplation
of the truth, in his
learning
how to
live
reasonably
and in his
knowing
how to
provide
the
material necessities
of
life.
These goals
give
rise
to
philosophy's three principal parts:
speculativa,
practica
and
/activa.
26
The
first, speculative philosophy,
is
made
up of
metaphysics, mathematics
and
physics. Metaphysics
treats the
most
common principles
and
properties
of all
being, whereas physics
treats of
everything
that
falls under
the
senses. Mathematics
is
two-fold: pure, which
studies entities
that do not
depend
on
motion
and are
abstracted from
it,
namely numbers
and
figures;
and
middle
(mathematica
media),
which studies
them
as
abstracted
but as
still found
in
motion,
as do
perspectiva
and
music.
27
Active
philosophy
has the
practical task
of
directing man's activities
precisely
as
human;
its parts are
ethics, which directs one's personal
life,
oeconomics,
which governs home
and
family,
and
politics, which orders
the
city
and the
republic.
28
Factive
or
constructive philosophy, otherwise
known
as
mechanica,
is
then divided into
arts that are
necessary
for
human
living
(e.g.,
agriculture), those
that are
useful
(e.g.,
navigation)
and
those
that
provide pleasure
(e.g.,
singing).
An
alternative division would
be
based
on matter: those preparing
it
(e.g.,
mining
or
metallurgy); those employing
25. Commentarla
una cum
quaestionibus
in
Vili libros Dephysica auscultatione,
first published at Cologne
in 1574 and often thereafter. Citations in what follows are taken from the Venice edition of 1600.
26. Toletus 1600, f. 2
ra
: 'Philosophia vero in hunc finem investigata, ut ignorantia, quam miser homo
propter peccatum incurrit, quo ad fieri posset, expelleretur, homo autem per peccatum haec tria
praeter alia sibi comparavit, rerum veritatis ignorantiam; eorum, quae secundum rationem agere
oportebat, similiter ignorantiam,
et rursus eorum, quibus ad vitae sustentationem, et
conservationem, propter peccatum indigebat, ignorantiam: unde omni ex parte ignarus factus est
in speculabilibus, agilibus, et factibilibus, indiguit igitur scientia, qua ens verum cognosceret, qua
agenda, et facienda consideraret: et ista est philosophia, in très praecipuas partes divisa secundum
ignorantiarum numerum, in speculativam nempe, qua veritates rerum tantum contemplaretur, in
activam,
qua ea quae secundum rationem agere oportet, doceretur, et in factivam, qua ea, quibus
exterius indigeret, facere sciret.'
27. Ibid.,
f. 2
rb
: 'Speculativa subdivitur in metaphysicam, quae omnium communissima principia, et
passiones
générales speculatur, in mathematicam puram, quae ea, quae secundum se a motu non
dependent, secundum rationem abstrahendo a motu tractât, ut figuras, numéros, et his accidentia,
et in mathematicam mediam, quae ea, quae secundum naturam suam abstracta sunt, in motu
tamen
considérât, ut perspectiva, et musica, et similes, et in physicam, quae res
sensibiles
speculatur.'
28.
Ibid.,
f. 2
rb
: 'Rursus activa dividitur in ethicam, qua homo ea, secundum quae se rationabiliter
ordinare debet cognoscit: et in oeconomicam, qua familiam, et domum regat: et politicam, qua
usus
reipublicae, et civitatis, cuius pars est, rectos cognoscat, et exequatur.'
Cambridge Histories Online © Cambridge University Press, 2008
Traditional
natural philosophy
211
it
in
construction
(e.g.,
building);
and
those using
the
things constructed
(e.g.,
military operations).
29
Physics,
or
natural philosophy,
had a
similarly broad scope. Basing
himself
on Simplicius
and
Themistius, Toletus first
gives
a
division based
on
the principles
of
natural things, treated
in the
eight books
of
Aristotle's
Physics, and on the
entities into whose composition they enter, discussed
in
the remaining natural treatises.
30
Natural entities
are
either simple
or
composed.
If
simple, they
are
incorruptible,
as the
heavens,
or
corruptible,
as
the
elements.
The
former
are
treated
in the
first
two
books
of
De
caelo, the
latter
in the
last
two:
elements
are
also discussed
in De
generatione
et
corruptione
under
the
aspect
of
their coming
to be and
passing away,
a
feature
they share with composites
or
compounds.
31
Composed entities
are
inanimate
or
animate.
The
inanimate again
are
of
two
types: those found
in
the upper regions, imperfect composites such
as
rain
and
things seen
in the
atmosphere, explained
in the
Meteorology,
and the
more perfect type found
in
the
earth, such
as
stones
and
metals, explained
in De
mineralibus.
32
Animate
entities then have
a
fuller treatment: their general features
are
discussed
in the
three books
of
De
anima,
after which come particular aspects
in books devoted
to
sleep
and
waking, youth
and old age,
life
and
death
and
so
on.
Finally there
are the
more specialised treatises devoted
to
specific
types
of
living
things: plants, studied
in De
plantis;
and
animals, studied
in
29.
Ibid.,
f. 2
rb
: 'Factiva rursus, quae mechanica dicitur, bifariam subdividi potest: primo in artes
necessarias, quae nempe usum vitae necessarium ministrant, ut lanificium, agricultura, aratura, et
in utiles, quae usum faciliorem vitae faciunt: ut in navigatoria, militaris, equestris, et in delectabiles,
quae usum vitae iocundiorem reddunt, ut saltandi ars, venandi, cantandi, et similes. Rursus dividi
potest in eas, quae materiam praeparant, ut ars fodiendi metalla, conficiendi ferrum, coquendi
lateres, et in eas, quae materiam disponunt, et componunt, ut domificatoria, fabrilis, sutoria, et in
eas, quae materia composita utuntur, ut militaris, equestris, navigatoria.'
30.
Ibid.,
f. 6
ra
:
'Circa
tertium de divisione philosophiae naturalis, videtur mihi
satis
commoda ilia,
quam
assignant Simplicius, et Themistius: nempe, haec quae in philosophia naturali continentur,
aut
sunt de principiis, aut de his, quae ex principiis componuntur, de principiis omnium rerum
naturalium,
et de communibus est liber physicorum, de compositis sunt reliqui.'
31.
Ibid.,
f.
6
ra
~
b
:
'Quae autem componuntur ex primis, aut sunt simplicia corpora ex
aliis
corporibus,
non constituta, aut sunt composita, et mixta. Si simplicia sunt, aut incorruptibilia, et sic sunt coeli,
de quibus traditur in libris duobus prioribus de caelo, aut corruptibilia, ut dementa, et de his agitur
in duobus posterioribus libris de caelo, de his enim omnibus primo traditur, tanquam de
simplicibus corporibus. De compositis vero, quia hoc omnibus est
commune, nempe generatio, et
corruptio,
et non solum his, sed etiam
ipsis
simplicibus elementis, ob id primo de generatione et
corruptione disseritur, postea de
ipsis
seorsum.'
32. Ibid.,
f. 6
rb
: 'Haec autem composita, quaedam inanimata, quaedam animata sunt. Primo de
inanimatis agitur: deinde de animatis. Atque inter ilia quaedam sublimia sunt, quae meteora
dicuntur,
quae supra nos fiunt, venti, pluviae, irides, halones, et similia, de quibus in libris
meteororum: quaedam subtus in intrinsecis terrae partibus, ut metalla, lapides, de quibus in libro de
mineralibus.'
Cambridge Histories Online © Cambridge University Press, 2008
212
Natural philosophy
the various books
De
animalibus
relating their history, modes
of
generation
and various parts.
33
From this overview
one may
gain
an
idea
of the
extent
of
natural
philosophy
in the
Renaissance mind.
The Physics
laid
out the
fundamental
concepts
of
all
the
natural
sciences
and
dealt with
the
type
of
question
now
discussed
in
courses
on the
philosophy
of
science.
The De caelo was the
equivalent
of
physical
astronomy,
the De
generatione
et
corruptione
of
physics
and chemistry
and the
Meteorology
and De
mineralibus
of
atmospheric
science
and
geology
respectively. Moreover,
the De
anima
explained
the
general principles
of
biology
and of
comparative psychology, while
De
plantis
and De
animalibus
covered
the
entire content
of
botany
and
zoology.
All
of
these disciplines were linked together
in a
common conceptual
structure,
so that a
change
in one,
particularly
in the Physics or the De
anima,
would
cause radical revisions
in
most
of
the others. There were also areas
of
ambiguity:
for
example, astronomy, where
the
heavenly bodies were
treated
as
physical entities
in the De caelo, and as
objects whose motions
could
be
calculated
in
middle
or
applied mathematics;
or
dynamics, where
motion
was
analysed
in
terms
of
its causes
and
properties
in the Physics, and
in terms
of the
forces
and
times required
to
move heavy objects
in
mechanics.
It was
precisely
in
these areas
that
conflicts
and
problems arose,
not
to be
solved until
the
seventeenth century with
the
rise
of
modern
science.
Also
worthy
of
note
is the
emphasis accorded various
parts
of
philosophy
in
the
curriculum,
for not all
were given equal
treatment.
In the
1580s
at
Pisa,
for
example, both
ordinarii
and
extraordinarii
(ordinary
and
extraordi-
nary professors) seem
to
have lectured
on a
three-year
cycle,
focusing
in
detail
on
particular books without regard
for
pedagogical order
in the
development
of
the doctrine.
34
In
1581
the
ordinarii
taught
the De
anima
and
the
extraordinarii the
De
sensu;
in
1582
the ordinarii
covered
the
first book
of
the
Physics and the extraordinarii the
De
generatione
et
corruptione', and
in
1583
the
ordinarii
lectured
on the De
caelo
and the
extraordinarii
on the
Meteorology.
The
year 1584
saw the
resumption
ofDe
anima,
and so on.
Each
year, however,
the
logic professor
at
Pisa taught
the Posterior
Analytics
and
33. Ibid.,
f. 6
rb
: 'Animata autem, quia animam habent communiter, prius de anima agitur in libris
tribus de anima, et de quibusdam ex anima procedentibus, videlicet de somno, vigilia, iuventute,
senectute, vita, morte, et similibus, in libro qui parva naturalia dicitur, tractantur. Post haec de
ipsis
animatis, atque horum, quaedam animalia, quaedam plantae: de animalibus in libro de historia, et
in libris de partibus animalium, et generatione ipsorum late disseritur: tandem de plantis.'
34. On philosophy instruction at Pisa, see Fabroni
1791-5 passim;
Schmitt 1981, § ix, 1983d; and
Wallace
1984, pp. 92-4.
Cambridge Histories Online © Cambridge University Press, 2008
Traditional natural philosophy
213
the
Isagoge
of Porphyry, so the student was always assured of beginning
logic
at any point in the philosophy
cycle.
35
At Padua, on the other hand,
there was an even greater degree
of
specialisation. In 1593, for instance, the
ordinarii
in philosophy taught the first and second books of De
anima,
while
the
extraordinarii
covered the third book; in logic the first and second books
of
the
Posterior
Analytics
were taught concurrently; and two commentaries
on the first book of the
Metaphysics
were offered, one in via
Scoti
and the
other in via
Sancti
Thomae.
In 1594 the concentration was on the first and
eighth books of the
Physics
and on the seventh book of the
Metaphysics,
following
a similar schema, with logic remaining the same. The subsequent
year
saw the ordinarii
covering
the De generatone et corruptione and the
extraordinarii
the De
caelo,
with the metaphysicians concentrating on the
twelfth
book of the
Metaphysics,
and the logicians continuing to
give
the
Posterior
Analytics.
30
In Rome, at the
Collegio
Romano, philosophy was
taught more systematically during the same period, so
that
a student at any
time could progress through his three years in the following order: first
year,
the whole of
logic,
from the
Categories
to the
Posterior
Analytics',
second year,
Physics,
De
caelo,
first book of De
generatone
et
corruptione
and
Meteorology,
and third year, second book of De
generatone
et
corruptione,
De
anima,
and selected books of the
Metaphysics
37
Even
from this brief survey it may be seen
that
natural philosophy
received
a major share
of
attention in the university curriculum. Little or no
attention seems to have been given at any
of
these institutions to the 'active'
or 'factive' branches
of
philosophy listed by Toletus, or to detailed studies of
minerals, plants, and animals as contained in the full
corpus
Aristotelicum.
PHILOSOPHY
AND THE
SCIENCES
It should be clear by now
that
the natural philosophy of the Renaissance
included much material
that
would later pertain to the sciences, in the recent
understanding
of
that
term. In one way
of
looking
at it, natural philosophy
may be regarded as the parent of modern scientific disciplines, for
considerable overlap may be discerned in the subjects of both. Yet in
another respect the Renaissance study of
nature
was deficient in its use of
observation and experiment, and generally in the role it assigned to
35.
Pisa,
Archivio
di
Stato,
Università
G.77, fF.
i64
v
-94
v
.
36.
Padua, Archivio
antico,
Università
di
Padova,
Rotuli
Artistarum,
Pars
prima
1520-1739,
cod. 242,
ff.
2
5
;-49
v
.
37.
Garcia
Villoslada
1954, PP- 84-115;
Wallace
1984, pp. 6-7,
58-70.
Cambridge Histories Online © Cambridge University Press, 2008
214
Natural philosophy
mathematics in its reasoning processes. The latter deficiency was gradually
remedied by the importation of materials from the
scientiae
mediae
into
natural philosophy, even though this was regarded by many as an illicit
crossing
of disciplinary lines.
38
To furnish some idea of the materials
appropriated by modern science from natural philosophy, and also
of
those
taken from the mixed science tradition, a few examples
will
now be
discussed.
These are drawn mainly from studies of the structure of matter
and the continuum and those relating to alteration and local motion, but
they are representative of changes taking place in other areas of investiga-
tion as
well.
Aristotle's
Physics
contained a number of teachings
that
proved fruitful
for
an understanding
of
matter and its structure. The hylemorphic doctrine
of
the first book required an exposition
of
the basic substrate or protomatter
underlying substantial change,
materia
prima,
concerning which a number
of
questions were raised in the sixteenth century.
39
One series had to do
with
the homogeneous or continuous character of the elemental bodies,
obviously
related to the problem of atomism and the structure of the
continuum, another to the presence of matter in the heavenly bodies and
what
kinds of changes the heavens might undergo.
With
regard to the first, in the thirteenth century Albertus Magnus had
suggested
that
minima
naturalia
might be identified with the atoms of
Democritus,
but otherwise did not develop the suggestion.
40
In the
fourteenth, under nominalist influences the question was broached anew
and assimilated to quantitative teachings on
maxima
and
minima.
Thus
Buridan focused attention on the quantitative requirements for the
existence
of natural substances, arguing
that
a substance becomes unstable
when
its quantity falls below the
minimum
naturale\
Albert of Saxony went
38. On the scientiae mediae, see Laird 1983; Reinterpreting
Galileo
1986, pp. 29-51
(Lennox);
the
difficulty
posed
by metabasis, or the use of
principles
outside
a
genus
subject
to
demonstrate
properties
of the
subject,
is
examined
in
detail
by
Livesey
1982.
39. Physics 1.7-9
(i89
b
30-i92
b
4);
philosophical
questions
relating
to
this
teaching
are
listed
by Mas
1599, PP-
368-449,
as
follows:
'Quaest.
1. An
detur
materia
prima,
368;
Quaest.
2. An
materia
prima
fuerit
in
tempore
producta
a Deo, 372;
Quaest.
3. An
materia
prima
sit ens, 375;
Quaest.
4.
An
materia
prima
sit
substantia,
377;
Quaest.
5. An
materia
sit
distincta
a
forma,
379;
Quaest.
6. An
materia
sit
pura
potentia,
382;
Quaest.
7. An
potentia
sit de
essentia
materiae
primae,
398;
Quaest.
8. An
materia
sit in
potentia
ad
omnes
formas,
408;
Quaest.
9. An
materia
habeat
potestatem
ad
formam,
quam
amisit,
411;
Quaest.
10. An
materia
appetat
formam,
413;
Quaest.
11. An
appetitus
materiae
reipsa
differat
a
materia,
415;
Quaest.
12. An
materia
prima
sit
ortui,
et
interitui
obnoxia,
418;
Quaest.
13. An sit
materia
prima
una
numero
in his
quae
oriuntur
et
intereunt,
421;
Quaest.
14.
An
materia
habeat
ideam,
426;
Quaest.
15. An
materia
ex se,
suapteque
natura
sit
intelligibilis,
428;
Quaest.
16. An
materia
prima
sit
bona,
nec ne, 432;
Quaest.
17. An
materia
sit
entium
omnium
infima,
et
ignobilior,
434;
Quaest.
18. An
materia
fuerit
aliquando
sine
forma,
439;
Quaest.
19. An
materia
possit
esse
sine
forma,
439;
Quaest.
20. Quid sit
materia
proxima,
et
quibus
discriminibus
separetur
a
prima,
448.' 40.
Albertus
Magnus
1890-9,
iv, p.
354
b
.
Cambridge Histories Online © Cambridge University Press, 2008
Traditional
natural philosophy
215
further to maintain
that
under normal conditions it could not exist below
that
minimum.
41
In the sixteenth century,
Nifo
cited approvingly
Averroes'
doctrine
that
every increase or decrease in a substance consists in
the addition or subtraction of a certain number of
minima
naturalia,
thus
emphasising the discontinuity involved in such processes. He also pointed
out
that,
when elements react upon each other, they are divided into
minima.
42
His contemporary, Julius Caesar Scaliger, theorised
that
the
minima
of different substances vary in
size,
and attempted on this basis to
explain
their coarseness and density.
43
He also argued
that
chemical
composition
(mistio)
is the motion of such
minima
toward mutual contact,
with
the result
that
union is effected. Toletus took up the same teaching:
reacting substances are divided into
minima
naturalia-,
in combination the
minima
of one substance come alongside those of the other, and they act on
each
other until a third substance, having the substantial form of the
compound, is generated.
44
Finally, in the early seventeenth century,
Sennert undertook a complete reconciliation of Aristotelian
minima
theory
with
Democritean atomism and went on to explain all known chemical
phenomena, involving both elements and compounds, in terms of their
ultimate material constituents.
45
An
analogous development took place with respect to Aristotle's analysis
of
the continuum in the sixth book
of
his
Physics.
There he had argued
that
the continuum could not be composed
of
indivisibles.
46
Nominalists
of
the
fourteenth century reopened the question, asserting
that
points are actually
present in extended magnitudes and using an example drawn from
mathematics to support this, namely
that
a sphere touches a plane at a point,
which
must therefore exist in the plane.
47
The sixteenth century saw
extensive
discussion of the mode of presence of indivisibles in the
continuum, for example, whether they are present actually or only
potentially, are infinite or finite in number and so on.
48
It was generally
conceded
that
indivisibles exercise a terminating or continuing function
41.
Van
Meisen
i960,
pp. 62-3. 42. Ibid., pp. 64-9.
43. Lohr 1980, pp. 714-16; Van
Meisen
i960,
pp. 73-7. 44. Van
Meisen
i960,
pp.
69-70.
45. Lohr 1980, pp.
725-6;
Van
Meisen
i960,
pp. 81-9;
Molland
1982.
46. Physics vi.i
(23i
a
2i-233
b
32);
Mas 1599, pp. 1181-1214,
lists
the
following
as
typical
questions:
'Quaest.
1. An in
continuo
dentur
actu
aliqua
indivisibilia,
1181;
Quaest.
2. An
punctum,
et
alia
indivisibilia
sint
entia
privativa, 1190;
Quaest.
3. An
indivisibilia
reipsa,
et a
substantia,
et a
magnitudine
distinguantur,
1193;
Quaest.
4. An
continuum
componatur
ex
indivisibilibus,
1197;
Quaest.
5. An
continuum
sit
divisibile
in
semper
divisibilia,
1205;
Quaest.
6. An in
continuo
dentur
actu
partes
infinitae,
1208;
Quaest.
7. An
magnitudo,
motus,
et
tempus
habeant
eandem
rationem
divisionis,
1212.'
47. Cambridge History 1982, pp.
573-84
(Murdoch);
Source
Book
1974, pp.
312-24;
Wallace
1984, pp.
165-6, 313.
48. Cambridge History 1982, pp. 567-73; Mair 1938;
Soto
1555, f.
42
v
-52
v
.
Cambridge Histories Online © Cambridge University Press, 2008
2l6
Natural philosophy
with
respect to the divisibles of which the continuum is clearly composed,
but only the divisibles were regarded as its parts. Some authors, however,
began
to
speak of
partes divisibiles
and
partes indivisibiles
as components
of
the
whole,
thus conferring on indivisibles the status of
parts
also.
49
Galileo
appropriated
this
terminology
and
spoke
of
parti quante and parti non quante
in the sensible continuum, conceiving them respectively after the fashion of
minute atoms and intervening vacua.
50
The latter could be infinite in
number, in his estimation, and he used them to explain the cohesion of
material substances on the basis
that
nature
abhors a vacuum.
With
regard to the heavenly bodies, the question of their constitution
was
argued extensively during the sixteenth century. The stimulus in this
area came from the mixed science of astronomy, where accurate measure-
ments
of
the positions
of
novae
and comets provided evidence
that
alterative
changes,
and not merely changes of position, were taking place in the
superlunary regions
of
the heavens.
51
The question whether the heavens are
simple or composed bodies had long been argued; Averroists thought of
them as completely simple, whereas most scholastics regarded them as
simple only in the sense of not being composed of the four sublunary
elements.
52
The latter position still allowed for the matter-form composi-
tion of superlunary bodies, but raised questions concerning whether their
forms are 'informing forms' or merely 'assisting forms' (i.e., intelligences
that
assist their motion), and whether their matter is the same as
that
of
sublunary bodies or not.
53
For Thomists, who regarded
materia
prima
as
pure potency and thus incapable of being intrinsically differentiated into
kinds, the admission of a second type of matter in the heavens presented
great difficulty. Capreolus and Cajetan offered ingenious suggestions to
explain
this possibility, but none was completely satisfying.
54
After
he
himself
had measured the parallax of the
nova
of 1572, Clavius concluded
that
superlunary bodies do undergo alteration (if not substantial change),
and in this sense are similar to the sublunary.
55
His researches stimulated his
49. E.g.,
Ruggiero
1590-1, f. 348
1
"
(lecturing
on the Physics at the
Collegio
Romano
in 1591):
'Quarto
animadvertendum
quod
totum
hoc
nihil
aliud significat
quam
quod
hoc
ipso
quod
assignamus
in
motu
aliquod
mutatum
esse,
i.e.,
aliquam
partem
indivisibilem
motus,
necessario
supponere
debemus
quod
illam
partem
praecesserit
aliqua
pars
divisibilis
eiusdem
motus';
see
also
Wallace
1984, p. 167. 50.
Galilei
1890-1909,
vii, p. 746.
51.
Tycho
Brahe
(Dictionary of Scientific Biography
1970-80,
11, pp.
401-16)
pioneered
in the
development
of
these
measuring techniques.
52.
Galilei
1977, pp.
81-92.
53. Ibid., pp.
103-58.
54. Ibid., pp.
139-47;
Wallace
1981a, pp.
160-90.
55. Clavius 1581, pp.
193-4:
'Quae
cum ita
sint,
ita
mihi
persuadeo,
stellam
illam
vel
tunc
a Deo Opt.
Max.
procreatam
esse
in
caelo
octavo,
ut
magnum
aliquid
portenderet
(quod
cuiusmodi
sit,
adhuc
ignoratur),
vel
certe
in
ipso
caelo
gigni
posse
cometas,
sicut
in
aere,
licet
rarius
id
contingat.
. . Hoc
Cambridge Histories Online © Cambridge University Press, 2008