Schmitt C.B. (ed.) The Cambridge History of Renaissance Philosophy
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Metaphysics
587
All
of
these authors, however, agreed
that
their explanation
of
traditional
doctrine had to be in accord with Aristotle's conception of deductive
science.
Aristotle's conception lent
itself
to their enterprise not only because
the articles of faith could be taken as the axioms or indemonstrable
principles for a deductive presentation of biblical and patristic teaching. It
also provided a systematic place for the apologetic side of the theologian's
task. With the expansion of Europe in the territories around the
Mediterranean basin and the increasing missionary activity of the newly
founded mendicant orders, the faith had to be presented not only to
believers
but also to Saracens, Jews and the pagan Tartars who had recently
invaded the Near East. While Christian doctrines could not be proved, it
was
thought
that
their acceptance could be shown to be at least reasonable
because they were congruent with fundamental philosophical doctrines like
the existence
of
God
and the immortality
of
the human soul. For this reason
revealed theology and metaphysics were brought together in
terms
of
Aristotle's
theory of science. According to the Philosopher the particular
sciences
have their own proper principles but
there
are common or general
principles for all the sciences. The scholastics proposed therefore employing
the articles of faith as the proper principles of theological science and using
Aristotelian metaphysics for the common principles of basic philosophical
doctrines.
76
It was, however, not only Aristotle's methodology
that
led the
theologians to opt for his programme as opposed to
that
of Anselm.
Aristotle's
ideas provided an ontological foundation for traditional theo-
logical
concepts, such as 'essence',
'nature',
'person' and 'subsistence' in
trinitarian
theory, and 'substance' and 'accident' in the theory of grace and
transubstantiation.
His
fixed
essences and static conception of reality
matched, moreover, their own hierarchical
view
of the world. Most
importantly, his conception of metaphysics as the science of being enabled
them to maintain the necessity
of
revelation for knowledge
of
God's
nature.
The
question of the proper subject-matter of metaphysics was, no doubt,
occasioned
by the ambiguities in Aristotle's presentation and by the
divergencies
among his Greek and Arabic interpreters, but it had its
theological
aspect as
well.
Medieval commentators on the Metaphysics were
forced
to take up the question whether Aristotle thought of his science as
first philosophy, divine science or the science of being. All the earlier
commentators, however, saw this question against the background of the
scientific
character of revealed theology.
76. See
Lang
1964;
Lohr
1985.
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Metaphysics
Thomas Aquinas, for example, clearly went beyond the literal
interpret-
ation of Aristotle's text when he held
that
the relationship of being in
general - the subject
of
metaphysics as the science
of
being - to the first sub-
stance - the subject
of
divine science - was one
of
causality. With one eye on
the theological doctrine of creation, Thomas explained
that
the subject-
matter
of
metaphysics is ens in
communi,
that
is, all the things
that
fall
under
the notion of'being in general', and
that
the doctrine of God was included
in this framework as the doctrine of the principle or cause of being. His
position served several purposes. First, it made it possible for him to
maintain the unity
of
metaphysics as a science, since according to Aristotle a
science
treats
not only the subjects belonging to its genus, but also their
essential properties and principles. Secondly, it enabled him to exclude the
possibility
of
an independent
natural
theology. For Thomas God is not one
of
the subjects metaphysics deals with, but their cause. Thirdly, Thomas'
position on the subject of metaphysics provided an argument for the
necessity of revealed doctrine. Although the theologian as apologist can
demonstrate God's existence on the principle of causality, God's
nature
remains beyond human understanding since our knowledge takes its
departure
from sense experience. In Thomas' succinct formulation, we can
know
that
God is, but not
what
he
is.
77
Metaphysical investigation aims at
the knowledge of God, but for the scholastic theologian this knowledge is
accessible
only to the believer.
Decisive
for the conception of metaphysics which was dominant among
scholastic thinkers during the period covered in this volume was the analysis
made by Duns Scotus, a thinker for whom the connection between
revelation and metaphysics as the science
of
being is even closer
than
it is for
Thomas Aquinas. Scotus begins with an examination of traditional
metaphysics which amounts to a critique of
natural
reason. Aristotle's
metaphysics, he maintains, does not get beyond physical reality. Because
he was compelled — not having access to revelation — to take sense
knowledge
as his point
of
departure,
Aristotle could discover principles and
draw conclusions, but apply them only in the physical order. His
metaphysics is consequently mixed with
error
and unable to answer
questions of God's
nature
and man's destiny. But the revelation of the
existence of spiritual reality has opened a new horizon for metaphysics.
Since
the mind is able to comprehend immaterial reality from the moment
that
it
attains
access to it, Scotus concluded
that
the first object of the
77.
Thomas
Aquinas
1963c,
1, p. 13 (1.3,
div.).
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Metaphysics
589
intellect is not the ratio quidditatis sensibilis, as Aristotle and Thomas had
maintained, but
rather
ens sub ratione ends — a concept which is so broad
that
it includes everything whose existence is not contradictory, which is
transcendent because it is anterior to all modes and determinations and
which
must be univocal because it applies to all things in the same way.
Duns Scotus pleaded accordingly for the elaboration of a new,
autonomous metaphysics, independent of the physical sciences. In
view
of
revelation it is possible to conceive a
pure
metaphysics, not limited by
human faculties
of
knowledge.
This new science
of
being would be open to
all
reality,
pure
knowing
of
pure
knowability. The subject
of
this science is
not, however, God as the personal,
triune
God known through revelation.
Such
knowledge is beyond science, which can deal only with universal
concepts. Metaphysics can grasp the divinity only as infinite being. In order
to be able to make certain assertions about immaterial reality Scotus
introduced, in addition to the simple properties of being like unity,
truth
and goodness, disjunctive transcendentals like act and potency, identity and
otherness, necessity and contingency, infinity and finitude. Whereas
Averroes
maintained
that
only physics, by beginning with motion, can
prove the existence
of
God
as prime mover, Avicenna made much use
of
the
dialectics of necessity and contingency in order to find a metaphysical
proof. For Scotus the most fundmental disjunction is
that
of infinity and
finitude. Since the members of the disjunction imply one
another,
the
metaphysician can conclude from limited being, known a posteriori, to the
existence of the other pole, unlimited being.
These conclusions involve some basic changes in the conception of
metaphysics in its relation not only to revealed theology, but also to the
speculative science of physics, which Aristotle regarded as 'second
philosophy' in opposition to metaphysics as 'first philosophy'. When the
metaphysician arrives at the knowledge of infinite being, he has the same
unclear and confused notion of God
that
one would have of man when he
knew only what the notion 'animal' means. Revealed theology as the
knowledge of a
triune
God is, therefore, still necessary, but metaphysics
with its analysis of the notion of being supplies the basis for its scientific
development. Moreover, since metaphysics as the science
of
being as being
excludes a
natural
knowledge of God as God, one might envisage the
possibility of a
natural
theology which had as its subject God as prime
mover, using physical proofs like those
of
Averroes.
In fact, one of Scotus'
pupils, Nicholas Bonet,
followed
this course, distinguishing for the first
time clearly between Metaphysica and Theologia naturalis in the titles of the
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590
Metaphysics
corresponding books
of
his philosophical
Summa.
Foreshadowing some of
the systematic works
of
the sixteenth century, his Metaphysica deals with the
nature
and subject of the science and the properties and categories of
being.
78
Finally, the notion of finite being, opposed to infinite being, but
including both immaterial and material reality, involves a category
of
being
unknown to Aristotle and makes possible the idea
of
a science which studies
corporeal reality in a metaphysical way, as ens mobile, in contradistinction to
the Aristotelian physics, whose subject is corpus mobile — a cosmology
distinct from natural science.
In spite
of
these efforts to establish an agreement between revelation and
the science of being, philosophy and theology in the course of the
fourteenth century drifted farther and farther
apart.
From the beginning of
the
thirteenth
century, when the schoolmen first
turned
their attention to
Aristotle
and the great scientific works of antiquity, an enormous amount
of
progress had been made in natural philosophy. By about the year 1300
the West had caught up with Islamic lands in the natural sciences and
surpassed them in technological innovation. These advances gained for the
university faculties
of
arts
a new autonomy. Freed from its traditional role as
the handmaid
of
theology,
the
arts
faculty became an institution equal to the
faculties
of medicine, law and theology. The breach became permanent in
the year 1277 through the condemnation by the Bishop of Paris of 40
theological
and 179 philosophical propositions. Since the philosophical
propositions were condemned on the ground
that
they entailed conse-
quences contrary to revealed teachings, the theologians were forced to
turn
their attention from the composition of systematic summaries of Christian
doctrine to the positive task of finding the sources
of
the propositions they
had regarded as axiomatic. At the same time the condemnation constrained
the philosophers to attempt to free natural science from the tyranny of
Aristotle's
worldview. The fact
that
many of Aristotle's doctrines - his
determinism, his notion of the eternity of the world, his denial of God's
power
to create an extramundane void or a plurality of worlds
—
were in
conflict
with Christian teachings made it impossible to maintain
that
he had
spoken the whole
truth.
A good
part
of the progress which was made in
fourteenth-century science was rendered possible only by a rejection
of
the
metaphysical assumptions which lay behind Aristotle's astronomy and
theory
of
local
motion or his neglect
of
certain areas in mathematics like the
theory of proportions and infinite series.
78.
Concerning
Bonet
see
Lohr
1972a,
pp.
284-6.
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Metaphysics
591
Throughout the fourteenth century the interest of the masters of
arts
centred on
natural
philosophy and the linguistic speculation which
accompanied it. Although the progress which was made in these fields
demanded a general reassessment of Aristotle's theory of science, meta-
physical
speculation on the
part
of scholastic
authors
during this period
seems to have dried up. Comparatively few commentaries on Aristotle's
Metaphysics were written, and among those
that
were one notes a shift in
attention
from the earlier
attempt
to forge a link between theology and
metaphysics to an effort to clarify the relationship between metaphysics and
physics.
Jean
Buridan, for example, who himself contributed much to the
fourteenth-century progress in
logic
and
natural
philosophy,
79
held
that
metaphysics is the most excellent of the speculative sciences because it is
prior to all the others. He paid deference,
of
course, to the idea
that
revealed
theology
is the most perfect science, but noted
that
it is a science sui generis
because it is founded on the articles of faith. Metaphysics is prior to
mathematics and physics because it is the most universal science, its subject-
matter
—
the concept
of
being
—
including not only material things, but also
immaterial reality like God and the intelligences. Metaphysics is also the
most certain of the sciences since it grounds the principles of all the
particular sciences, while its own principles are evident and universally
valid.
But although Buridan
thus
emphasised the role
of
metaphysics as first
philosophy, he questioned Aristotle's division of the speculative sciences
according to degrees of abstraction from
matter.
He maintained
that
metaphysics and physics both deal with the same subjects: things mutable
and immutable, their causes, the prime mover. They differ, however,
because physics considers the principles
of
things to the extent
that
they are
principles of change, whereas metaphysics considers them as the principles
of
being.
The task
of
demonstrating the existence
of
God
belongs therefore
only
to metaphysics. Physics cannot ascend beyond an immaterial prime
mover or prove
that
the prime mover it discovers is identical with God.
The
field in which the greatest advances in
natural
philosophy were made
was
that
known as the latitudo
formarum
or the mathematical theory of the
intensity
of
qualities. This theory was related to metaphysical notions which
were revolutionary and which, had they been exploited, would have meant
the end of the static, Aristotelian conception of reality. The theory of the
latitudo
formarum
had its origin in one of those strange combinations of the
theological
with the philosophical which characterised scholasticism. For
79.
Concerning
Buridan
see
Lohr
1970, pp.
161-83;
A.
Ghisalberti
1975.
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Metaphysics
the schoolmen,
following
Aristotle, virtues like charity and qualities like
heat were accidental forms. In order to deal with such problems as the way
in which a person grows in charity or a body grows
hotter,
Duns Scotus
suggested a quantitative
treatment
of increases or decreases in a quality
(heat) by way of the addition or subtraction of degrees of intensity
(temperature). By a quantitative
treatment
Scotus meant not simply an
extrinsic assimilation of quality to quantity. His suggestion is
rather
connected with the idea of degrees of perfection which is implicit in his
dialectical
approach to reality. Since the
terms
'infinity' and 'finitude'
originally
refer to quantity, they cannot be transferred without qualifica-
tion to perfections which have no dimensions. He distinguished therefore
between a
quantitas
virtutis,
referring to the intensity of a perfection and
admitting an actual infinity, and a
quantitas
externa, characterised by
three
dimensions and admitting only a potential or indefinite infinity. It was in
the former sense
that
the late fourteenth-century scholastics understood the
measure of the intensity
of
a quality (temperature, for example) and not as
the extension of a quality in a subject (the quantity of heat).
In accordance with the general tendency in Renaissance thought to
emphasise the dynamic aspect of reality, the masters in the faculties of
arts
concentrated on the problem of variations in intensity, especially in
connection with local motion. At Oxford methods were developed to
express the amounts by which a quality (the local motion, say, of a free-
falling
body) increases or decreases in intensity (velocity) as a function
of
its
extension (time). On the basis of this work a radically new conception of
geometry made its appearance at Paris. Nicole Oresme advanced the idea of
representing the
rate
of change of an intensity graphically by plotting
intensity as a latitude (ordinate) against extension as a longitude (abscissa).
The
notion of expressing continuous variability in
terms
of coordinates
marks a break with the static geometry of
pure
form which the West had
inherited from antiquity in favour
of
a geometry
of
motion in which figures
are generated by the movements of points and lines. The difference of
approach may be illustrated by two possible
ways
of formulating
definitions in geometry. The circumference of a circle can be defined
statically as the locus
of
all
points in a plane at a
given
distance from a centre
or dynamically as the curve generated by a point moving in a plane at a
constant distance from a centre.
The
metaphysical significance
of
these developments lies not only in the
fact
that
we encounter in them the same dynamic
view
of reality
that
we
have found in writers like Ramon
Lull.
They are also
important
because
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Metaphysics
593
they led some scholastic theologians to attempt to generalise the ideas
of
the
masters
of
arts.
Jean
de Ripa, a Franciscan theologian who read the Sententiae
at Paris at about the same time
that
Oresme's work was published, took the
decisive
step. Whereas the work of the artists concerned accidental forms,
Ripa
introduced the notion of variability into substantial forms. In
connection with the fourteenth-century debates about the beatific vision,
he sought to define the conditions under which a union of creature and
creator is possible. For this purpose he had recourse to the Scotist dialectic of
infinity and finitude. But whereas Scotus emphasised the contingency and
the structural not-being which finite reality includes, Ripa attempted to
define the upper limits of the activity of finite reality. For him forms are
accordingly
not static, immutable essences, but include an ontological
intensity which can be measured as a distance between the relative
nothingness of finite reality and a supreme terminus to which it tends as to
its own unattainable perfection.
80
Both forms
of
the latitudo
formarum
then
found their place in the metaphysics of Paul of
Venice.
Paul, who brought
these doctrines from Oxford and Paris to Padua about the beginning
of
the
fifteenth century, not only included the latitudo
formarum
under the
categories quality and habitus, but also recognised a latitudo perfectionalis
entium, or grades of ontological perfection measured according to their
distance from a zero degree. It was probably in this form
that
Nicholas of
Cusa
became acquainted with the doctrine during the period
of
his studies
in the University of Padua.
Nicholas
knew the works of Archimedes and the discussion of Zeno's
paradoxes in the Parmenides (i28ff.) of Plato, but when he sought
mathematical symbols to illustrate his conception
of
metaphysics he
turned
not to the classical geometry of form, but to Oresme's new geometry of
motion. Nicholas approached the problem in terms of knowledge
rather
than
of being. He sought to aid the mind in its ascent to the absolutely
infinite by way of
three
steps.
81
The first was the consideration of finite
mathematical figures, figures which are generated by the motion
of
points,
lines and planes.
Just
as for Oresme a line was generated by the motion
of
a
point, so also Nicholas defined the line as the unfolding or explication of a
point. From the new geometry's concern with the problem of continuous
variation, he concluded
that
knowledge consists in the determination of
proportions or ratios and
that
perfect exactitude in measurement is
consequently unattainable. In a second step the mind ascends by transferring
80.
Concerning
Jean
de
Ripa
see
Combes
1956;
Vignaux
1959.
81.
Nicholas
of
Cusa
1932-,
1, pp. 24-5 (De docta ignorantia 1.12).
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Metaphysics
these considerations to infinite figures. From the method of definition of,
say,
a point along a line in terms of its movement from a minimum to a
maximum value, Nicholas learnt the correct method of dealing with the
infinite and the infinitesimal not merely as potentialities, but as the
actualities which are the upper and lower limits of the activity of finite
reality. Wanting to illustrate his idea
that
for the understanding
of
dynamic
reality a transcensus from rational to intellectual knowledge is necessary, he
took the example
of
a polygon as a variable magnitude inscribed in a circle.
For rational knowledge the polygon and the circle are
fixed
essences which
exclude
one another, because according to the principle
of
contradiction an
attribute
cannot at the same time belong and not belong to a subject. But if
we,
by conjecture, imagine a polygon the number of sides of which
increases to infinity, we can see, by the vision of the intellect,
that
the
polygon
with a maximum number of sides
will
coincide with the circle.
This
is a conclusion which is not bound by the limitations of empirical
observation and to which the intellect cannot withhold its assent. In a
third
and final step the mind then extends these conclusions to the absolutely
infinite God. Oresme had remarked
that
for a form which was represented
graphically
by a semi-circle the
rate
of change reaches a minimum at the
point of maximum intensity. Similarly, Nicholas maintained
that
in the
absolutely infinite One, to whom no finite thing can be set in proportion,
maximum and minimum coincide.
The
fourteenth-century achievements in natural philosophy were not
limited to physics and geometry. Important advances were also made in
chemistry,
geology
and
biology
—
sciences to which Albertus Magnus had
given
the impetus a hundred years earlier. Among the works which formed
his Aristotelian encyclopaedia
of
the sciences, the commentaries De meteoris,
De
mineralibus and De animalibus enjoyed a vast manuscript diffusion in the
fourteenth and fifteenth centuries. Problems like the pre-existence
of
forms
in
matter,
the persistence of elemental forms in compounds and the way
that
the soul informs the embyro were discussed at Paris in terms of his
synthesis. But because Aristotle's encyclopaedia was understood as a system
of
the sciences, some Parisian masters
of
arts
at the beginning
of
the fifteenth
century also
turned
their attention to Albertus' Metaphysica and Liber de
causis et processu universitatis for the philosophical foundations for the
solution of such problems. In these authors we encounter a
view
of reality
not unlike
that
which we have discovered in
Lull,
Nicholas
of
Cusa
and
Jean
de Ripa. In dealing, for example, with the traditional question of the
distinction between essence and existence, Johannes de Nova Domo, who
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Metaphysics
595
taught in the
arts
faculty at Paris until about 1420,
82
employed the dynamic
image
of
a river flowing from its source and maintained
that
the essence
of
a
thing is
that
from which its existence proceeds. For the intrinsic term
of
such
activity
he spoke of an esse essentiae, and for the extrinsic term, of an esse
existentiae. Since the distinction between essence and existence is
thus
not a
real one, Johannes rejected the opinion - proposed by Thomas Aquinas -
that
spiritual beings each form a distinct species and held
that
they are
numerically distinct, the principle
of
individuation among them being their
quod
est.
The
significance
of
the authors
like
Johannes de Nova Domo who
turned
to Albertus' metaphysical works lay not only in the fact
that
they sought to
transform the traditional scholastic encyclopaedia of the sciences by
integrating into it the active conception of reality which had been
developed
by some
of
the masters
of
arts. They also attempted explicitly to
incorporate the earlier writers we have considered in the first section
of
this
chapter into their synthesis. They seem to have known Ramon
Lull
through
the works which he left to the Carthusian monastery
of
Vauvert
near Paris.
Heimeric de Campo, who taught in the
arts
faculty at the University of
Cologne
from about 1425, seems also to have learnt
of
the speculative side of
Lull's
thought through Nicholas of Cusa. He had studied at Paris under
Johannes de Nova Domo and met Nicholas at Cologne when the latter
arrived
there
from Padua. Heimeric took up Lull's understanding
of
reality
as a triadic structure, but he attempted to bring it into accord with
scholasticism by expressing it in terms
of
Johannes' distinction of essence,
existence and quod est.
Heimeric was aware
that
Lull's
view
of
reality implied an understanding
of
the relationship between faith and reason radically different from
that
which
the scholastics had worked out in the
thirteenth
century. In the
scholastic understanding the task
of
the theologian was to present Christian
doctrine systematically. Reason had the function
of
ordering the data; faith
provided the principles for the presentation. In Heimeric's understanding,
as in
that
of
Lull,
faith provided a conjecture or hypothesis which the
intellect sought to understand by eliminating other possibilities. This was
not simply a theoretical question; it concerned the structure of medieval
society
itself. Specific to scholasticism was the notion
that
the presentation
of
Christian doctrine should be in accordance with Aristotle's theory of
science.
The scholastics took the articles of faith as the indemonstrable
82.
Concerning
Johannes
de
Nova
Domo
see
Meersseman
1933-5,
passim;
Lohr
1971, p. 264.
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Metaphysics
axioms
for the presentation because thereby the clergy's understanding of
itself
as the interpreter
of
the tradition was assured. The fourteenth-century
progress in natural philosophy implied a different understanding of
Aristotle's
theory
—
science as research
rather
than
as deductive presentation
-
and a different conception
of
the scientist: as a seeker after
truth
rather
than
as a member of a privileged class in possession of it. But up to Heimeric's
time the masters
of
arts
seem to have taken the institutional structure of the
university as
given
and concerned themselves
rather
with the solution of
individual problems in natural philosophy
than
with the theory of science
which
their work implied.
The
inner crisis which
thus
affected scholasticism at the beginning of the
fifteenth century was also concealed by the understanding
of
metaphysics as
the science
of
being.
As divine science metaphysics clearly belonged to the
theological
faculty's domain, but as first philosophy it was the concern of
the masters of arts. Metaphysics was understood as the science of being in
order to bridge this gap, but the Albertist attempt to understand essence and
existence in a new way brought the crisis to the surface. We do not know
how
Heimeric would have solved the problem of clerical and lay
participation in science, but his approach can perhaps be divined by his
position in the conciliar debate. Employing the distinction between essence,
existence and quod est, he understood the church as composed
of
an apostolic
shepherd who governs and a catholic
flock
which
gives
its consent, both
brought together in a conciliar fold. His Lullian interpretation of the
Albertist
distinction
thus
enabled him to assert to the
full
two rival concepts
of
ecclesiastical
authority, the hierarchical and the popular. But this solution
could
only serve to make more critical the situation of metaphysics as the
science
of being between a clerical theology founded on revelation and a
secular science based solely on human reason.
The
new science was a source
of
concern to many who saw the tradition
of
evangelical faith endangered by rationalism and extreme realism.
Jean
Gerson, Chancellor of the University of Paris and a leading figure at the
Council
of Constance,
83
maintained
that
revelation is the foundation
of
all
the sciences because metaphysics (as first philosophy) grounds the particular
philosophical disciplines and for metaphysics revelation is necessary.
Because
the sciences can only comprehend the essences of things through
concepts, they deal with an intra-mental world. The function
of
metaphys-
ics
is to establish contact with extra-mental reality through the concept of
83.
Concerning
Gerson
see
Bauer
1973.
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