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Dictionary of the History of Ideas

Studies of Selected Pivotal Ideas

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The doctrine of double truth first appears in 1277
as part of the introduction to a Church condemnation
of heterodox ideas. In this document the Bishop of
Paris, Stephen Tempier, declares that certain masters
in the Parisian Arts Faculty “hold that something is
true according to philosophy but not according to the
Catholic faith, as if there are two contrary truths, and
as if in contradiction to the truth of Sacred Scripture
there is a truth in the doctrines of the accursed pagans.”
The same proposition may be true and false simulta-
neously, true in philosophy and false in theology—such
is the condemned doctrine of double truth. Unready
to accept this denial of the law of contradiction, which
he sees as a device to assert heresy, the bishop then
lists 219 condemned errors. The masters of arts are
warned not to teach them on pain of excommunication.
Although the thirteenth-century Averroist Siger of
Brabant, and his contemporary Boethius of Dacia are
the only two masters mentioned by name in the con-
demnation, the list of heterodox propositions is so broad
that it includes doctrines taught by Saint Thomas.

In two senses the condemnation represents a crisis
in the Western Latin mind. In the narrower sense, it
is an attempt on the part of the Parisian Faculty of
Theology to stop philosophical speculation in the Fac-
ulty of Arts, especially when that speculation abandons
the traditional guidance of theology and openly pro-
fesses heterodox doctrines. At the time of the orga-
nization of the University in 1200, the greater part of
Aristotle's works was already available in Latin trans-
lation. As the higher of the two faculties, the Faculty
of Theology wished to assert its control over the study
of these new doctrines, particularly the dangerous ideas
found in the libri naturales and the Metaphysics. From
the very beginning theologians were suspicious of their
contents. In 1210 and again in 1215 the public and
private teaching (though not private reading) of Aris-
totle's works was banned at the University. Yet the
theologians themselves soon began to be impressed
with the tremendous power and comprehensiveness of
Aristotle's doctrines, and in 1231 Pope Gregory IX
decided that Aristotle might be taught at Paris if his
errors were first expurgated. With this limited ap-
proval, the knowledge of Aristotle increased and by
1243 the commentaries of Averroës became known.
Although the ban against an unexpurgated Aristotle
was still in effect at the University in the 1240's, it
was not always upheld. For example, in 1245 Roger
Bacon lectured in the Arts Faculty on the complete
Physics and Metaphysics. Nevertheless conflict did not
break out between the two faculties, probably because
the masters of arts continued to quote Saint Augustine
with respect, and to dismiss discreetly any heterodox
doctrine of Averroës or Aristotle. When the split finally
opened in the 1260's, the cause was not difficult to
find. Led by Siger of Brabant, the masters of arts were
openly professing heterodox Arabic-Aristotelian con-
cepts in disregard of the doctrines of revelation. Thir-


teen doctrines, condemned in 1270, were included in
the great condemnation of 1277.

In the larger sense, the condemnation represents
more than the professional rivalry of two faculties. For
the theologians were the guardians of the Augustinian
tradition which had been dominant in medieval
thought up to this time. Augustinianism had made its
peace with pagan philosophy by absorbing the spiritual
orientation of Neo-Platonism while subordinating it to
Christian revelation. The Augustinian universe consists
of a static, hierarchically ordered series of beings cul-
minating in the Supreme Being who has created all
from nothing. Through his omniscience, the Divine
Being knows all; through His mercy He provides for
all; through His freedom He orders all to His will. The
Arabic-Aristotelian view, now championed in the Fac-
ulty of Arts, stands in dramatic opposition to this. The
universe is moved by the Prime Being, the first of the
separated Intelligences. Emanating from this Intelli-
gence are the other Intelligences, the heavenly spheres,
and finally the earth as the arena of generation and
decay. The entire emanation proceeds by an eternal,
necessary movement, controlling the Prime Mover
Himself. Such a God can only produce an effect similar
to Himself: a unique, undifferentiated substance. The
multiplicity of effects in the world, then, presupposes
the multiplicity of intermediary causes, rather than the
direct activity of God. It follows that God acts through
the heavenly Intelligences which in turn produce the
multiplicity of things on the earth. The Intelligences
thus become the immediate causes of earthly effects.

Here then we have a dramatic contrast: a free,
personal deity as opposed to an impersonal deity
moved by necessary causes; a created universe as op-
posed to an eternally emanating one; a knowing God
as opposed to one who knows only himself; a being
who acts directly on the earth as opposed to one
who acts through the intermediaries of the Intelli-

To illustrate this crisis more concretely and to show
the origin of the doctrine of double truth, we must
isolate several of the condemned propositions. As we
have seen, Aristotle and Averroës held the eternity of
the world; it was moved by a Prime Mover who acti-
vates necessarily the Intelligences of the heavenly
spheres. This denied creation ex nihilo of Genesis, and
the freedom and providence of a personal deity. More-
over, an eternal movement is constant and absolute,
and the nature produced from such a movement ex-
hibits the same features: there can be no interruption
of the laws of nature. Hence there can be no miracles
performed by a personal God or His messengers.

In the second place, Aristotelian psychology, at least
as interpreted by Averroës, denied the immortality of
the individual soul. For Averroës the only immortal
soul is a divine intellect which at times unites itself
to man. This union produces an “acquired intellect”
which gives man the power to know. As the title
“acquired” makes clear, this intellect—the only human
one which knows—is not intrinsic to man. In other
words the intellect for man is not an inherent form
but an assisting form. Since the “acquired intellect”
is produced only when the vegetative and sensitive
functions operate, their cessation at death entails the
destruction of the “acquired intellect” and the whole
human soul. Only the divine intellect remains and is
immortal. It is the one, true intellect for all men. This
is the famous doctrine of the unity of the intellect,
a doctrine which destroys the Christian concepts of
personal immortality, salvation, and resurrection.

Finally, other condemned ideas attack the very basis
of the Christian religion by asserting that philosophy
is the highest wisdom. In contrast, Christianity is pic-
tured as containing falsehoods “like all other religions”
and is held to be based on myths and fables. Although
the notion that philosophy is the supreme wisdom is
found in some thirteenth-century thinkers, the idea that
Christianity is false or mythical only appears for the
first time with John of Jandun in the early fourteenth

What did the masters of arts actually say in profes-
sing these doctrines of the “accursed pagans”? Did they
attempt to avoid conflict with revelation by saying that
there are two contradictory truths?

There is no doubt that the most famous master of
arts, Siger of Brabant, taught many of the condemned
doctrines. At various stages of his career, he held the
unity of the intellect and consequent mortality of the
soul, the eternity of the world, and the regularity of
natural change prohibiting miraculous interruption.
Though his attitude shifted at various times (usually
under the pressure of attacks from the Faculty of
Theology), he never admitted the possibility of two
contradictory truths. Nowhere in his writings does the
term “double truth” appear, nor do we ever find the
statement of two contrary truths as set down in the
1277 condemnation. On the other hand, there is a good
deal of evidence to indicate that Siger upheld the law
of contradiction, thus explicitly denying the possibility
of a double truth. In his Questions on Metaphysics IV,
he says that we cannot maintain contradictory points
simultaneously for that is to deny what we affirm. The
mind itself, he holds, will not allow adherence to con-
tradictory propositions. Even God does not produce
such contradictions for He will not make man into an
ass. With this explicit acceptance of the law of contra-
diction, the problem remains of Siger's acceptance of
the teachings of Greco-Arabic philosophy and his si-
multaneous insistence on the validity of Christian


Siger's solution to this problem consists of three
different attitudes adopted at various points in his
teaching. The first attitude, common throughout his
work, is the assertion that faith is true while the doc-
trines of Aristotle are merely the conclusions of philos-
ophy and reason. The word “truth” always appears
associated with faith and in opposition to the teachings
of Aristotle and reason. Prescinding from faith, Siger
argues, we must investigate nature with Averroës and
Aristotle as our guides. Our conclusions, however, are
not true but simply the rational deductions of pagan
philosophers. In its most radical form, this attitude
expresses itself as the reduction of philosophical inquiry
to the doctrinal history of previous thinkers. When we
proceed philosophically, says Siger, we examine the
opinions of the philosophers, not the truth of the

But this attitude did not always satisfy him. Time
and again we find the assertion that the doctrines of
nature are not simply those of Aristotle and Averroës
but also the conclusions of reason. Unlike the first
attitude which tends to identify reason with the doc-
trines of Aristotelians, here reason becomes separated
from the philosophers; it produces a knowledge inde-
pendent of their teachings. At times the arguments of
natural reason appear “almost irrefutable.” Yet faith
contradicts them, and we must accept many things on
faith which “human reason leads us to deny.” A strict
antinomy develops between knowledge and faith: “I
know one thing; I believe another,” says Siger. There
is an epistemological basis for this attitude. Natural
philosophy, according to Siger, presents us only with
those laws established by human reason. Because God
is above rational laws, it follows that He may interrupt
them, not to produce absurdities but to complete the
inadequacies of human reason. The truth of faith is
not denied by contrary assertions of natural reason
because revelation itself derives from a source inacces-
sible to human reason.

Siger's insistence on the great value of autonomous
philosophy and the wisdom it produces leads him to
adopt still a third position. Impressed with the nature
of philosophy, Siger does not always reserve the word
truth for faith alone and he seems at least implicitly
to assert a double truth. In the Commentary on the
Metaphysics, he says: “The knowledge of truth belongs
principally to philosophy because it has for its object
the first causes and the first principles—thus the first
truths.” And in the Commentary on the De anima, he
holds that the knowledge of the soul gained by philos-
ophy is important for truth. If philosophy establishes
true principles and faith is still true, it seems difficult,
in cases of specific doctrinal conflict, to avoid the
statement that two contradictory truths actually exist.

The solution to this dilemma stems once more from
epistemological considerations. The highest truth, Siger
holds, can only result from the knowledge of causes
in themselves and not as they are inferred from effects;
in Siger's language we must have knowledge of causes
per se. Now all arguments of reason are generalizations
from sense perception which enable us to describe
nature not through its own causes but only through
effects registered on the mind. When set down into
laws, such effects can never provide final certainty
because they do not establish the causes per se of the
things they purport to describe. This reduces all philo-
sophical knowledge to a probable or hypothetical

In effect Siger has established degrees of certitude.
Faith is absolutely certain even though it is not
demonstrable to reason. Rational inquiry limited, as it
is, to God's effects cannot attain to the causes per se
of these effects. For we cannot describe the mode of
God's activity per se which in the end is the cause
of the principles of nature. Rational demonstrations
therefore which appear final and irrefutable are such
only within natural limits, and consequently their
demonstrative status is only probable. In several places,
Siger endorses this probabilism: “We have demon-
strated above that the effect of God is eternal; this
conclusion is probable but not necessary”; “The argu-
ment of Aristotle is probable; it is not necessary”;
“Although the argument of the Commentator has
probability, it is not true” (Muller, 1938).

The second thinker mentioned in the 1277 condem-
nation, Boethius of Dacia, adopted essentially the same
attitude as Siger. The method of natural philosophy
must limit itself to natural causes and principles. On
these principles alone, we must accept the eternity of
the world, says Boethius. Although these principles
hold within the natural order, supernatural principles
may suspend them, not by demonstrating their falsity
(that is impossible) but by asserting the opposite on
grounds of revelation. Again we are faced with relative
degrees of certitude rather than the absolute validity
of contradictory truths. Even though Boethius praised
the life of philosophy in his De summo bono as the
pursuit of speculative truth and as the worthiest life
for man, we must bear in mind that these concepts
are relative to the natural order of philosophy. No-
where are they asserted absolutely as the 1277 con-
demnation claims.

There appears to be no reason to doubt the sincerity
of Siger and Boethius in their proclamations of loyalty
to the Christian religion. They were not secret atheists
or rationalists. Sincere Christians, they were confronted
with a dramatic gulf between their deeply held reli-
gious beliefs and the conclusions of their philosophical
pursuits. They adjusted the conflict by setting the
Christian God totally outside the natural order. Then


they declared all descriptions of that order, produced
by philosophy, to be statements of a limited, probable,
and hypothetical nature. The doctrine of double truth
or two contradictory truths was imposed on them by
their adversaries who, by reading it into their state-
ments, hoped to end speculation they considered

The 1277 condemnation effectively ended philo-
sophical speculation in the Faculty of Arts until the
end of the century. In the fourteenth century, however,
the masters of arts were once again allowed to take
up the doctrine of the Stagirite and his commentators.
On the testimony of two chancellors of the University,
Jean Gerson and John Buridan, we learn that the mas-
ters of the Faculty of Arts were permitted to consider
these doctrines provided they took an oath swearing
to uphold the doctrines of revelation. When expound-
ing pagan ideas contrary to faith, the Parisian masters
had to swear that they would demonstrate the falsity of
those views in conflict with faith. In order to do this
the masters asserted the necessity of giving a complete
exposition of pagan doctrines.

The situation can be well illustrated by considering
the thought of John Buridan, onetime chancellor of the
University, and one of the most influential scholastics
of the century. Like Siger, Buridan accepts the mortal-
ity of the soul and the eternity of the world as the
doctrines of philosophy. Establishing these doctrines,
however, requires that we understand the nature of
philosophical statements. All such statements are
merely probable because philosophical inquiry pro-
ceeds by three modes of understanding—experience,
memory, and induction—which derive from sense per-
ception. Since Buridan grants a realm of final truth
above sense perception, it is clear that empirical
knowledge does not arrive at ultimate certainty.

When we compare the probable philosophical theses
of Siger and Buridan, the major difference we discover
is the growth in Buridan of a natural philosophy inde-
pendent of Aristotle. The tendency of separating reason
and nature from the ideas of the philosophers—already
apparent in Siger—is much more marked in Buridan.
As a result, it is impossible for Buridan to argue that
he is merely reporting the opinions of previous philos-
ophers. From his many criticisms of Aristotle, it is quite
evident that he intends to establish an independent and
objective natural science. The assertions of philosophy
become the descriptions of nature, and Aristotle him-
self is often rejected in the name of natural reason.
Nevertheless, Aristotle's authority still stands so high
that only when Buridan agrees with the Stagirite does
he vigorously defend a philosophical position in sharp
opposition to faith.

The development of a philosophical probabilism can
be seen in Buridan's treatment of creation ex nihilo.
Creation out of a void, he holds, must be accepted
on faith but the notion that every existing being implies
a preexisting being is valid for philosophy. Thus, ac-
cording to philosophy, we must hold the eternity of
the world which, in turn, throws into question the
immortality of the soul. For if the world is eternal and
souls immortal, an infinite number of souls will be
wandering around the universe. To avoid this absurdity,
the logic of natural philosophy demands that we deny
the immortality of the soul. On the basis of natural
philosophy, arguments for mortality may be derived
either from Averroës' view of the unity of the intellect
or the Aristotelian Commentator Alexander of Aphro-
disias' (fl. 200) view of the corruptibility of individual
souls. Buridan chooses the Alexandrist position: the soul
is a form educed from the potency of matter, extended
to the extension of matter, multiplied in distinct bodies,
and finally generated and corrupted. This is the objec-
tively correct doctrine of natural philosophy. However,
Buridan decides that the doctrine of faith is true: the
soul inheres in matter but is eternally immortal after
death. For the argument of natural philosophy, he
concludes, is only probable and must give way before
the irrefutable truths of divine revelation.

The most radical Parisian master of the fourteenth
century, John of Jandun (d. 1328), continues the tradi-
tion of Siger in several ways. Jandun upholds individual
mortality on Averroistic grounds, explicitly rejecting
the “vile error” of Alexander that the soul actually
informs the body. The soul is not created but coeternal
with the world. The opposite view of faith, while not
demonstrable to reason, is true. God produces this by
a miracle not apparent to sense perception: He makes
the corruptible soul immortal.

In Jandun, the status of natural philosophy is also
raised, as in Buridan, to that of an independent, objec-
tive description of nature. Thus the doctrines of natural
reason, derived ultimately from sense perception, pro-
vide philosophic proofs whose demonstrative status is
logical not simply historical: these are not merely the
proofs of Averroës and Aristotle, but the independent
conclusions of reason. Precisely because these laws are
derived from rational demonstrations based on sense
perceptions, they are not absolutely true. They must
be rejected when they conflict with revelation.

Despite differences in the interpretation of the doc-
trine of the soul, both Buridan and Jandun subscribed
to Siger's original division of probable philosophical
demonstration vs. absolute revealed truth. A new ele-
ment, however, enters with Jandun. We find the first
written statements of those condemned propositions of
1277 which spoke of Christianity as full of errors and
based on fables and myths. In his Commentary on


Aristotle's De anima, Jandun notes that Averroës at-
tacks the strength of custom. It is custom alone, says
the Commentator, which accounts for the strength of
religions. Men come to accept the fables and puerile
notions inherent in religious belief only because they
have heard them from childhood. And in the Com-
mentary on the De caelo et mundo, Jandun notes that
Averroës refers to religion in a derogatory sense in his
prologue to Aristotle's Physics, Book III. There the
Commentator holds that the doctrines of religion are
apologies established by religious lawmakers for the
control of the common people; these doctrines corrupt
necessary principles and are “removed from truth and
the human mind.” The Commentator, Jandun adds, is
speaking of the Muslim religion, “and if he should
speak of our religion he would lie because all things
in our religion are true and proved by the miracles
of God and the glory of the Creator.” It is important
to note that Jandun may be perfectly sincere in this
statement. And it is equally important to say that once
stated, the notion that religious belief is a human in-
vention reinforced by conventional usage would gain
increasing currency.

We can begin to see this development in the late
fourteenth and early fifteenth centuries. Particularly
at the northern Italian Universities, organized without
faculties of theology, we find an increasing emphasis
not only on independent philosophical speculation but
also on philosophical attacks on religious truth. Most
thinkers continued to adhere sincerely to the earlier
divisions which established for the masters of arts a
method distinct from that of theology. But there were
some who denied the probable nature of philosophical
conclusions, asserting instead the absolute truth of
philosophy, and thus turning philosophical criticism
against Christianity itself.

Perhaps the outstanding example of this develop-
ment is Blasius of Parma (d. 1416). Active in Pavia,
Padua, and Bologna in the late fourteenth century,
Blasius was professor of astronomy, mathematics, and
philosophy. He establishes the mortality of the soul by
proving that the soul has no function independent of
bodily powers. Knowing, the highest function of the
soul, depends on the continuous operation of the sensi-
tive powers; and the eventual dissolution of the sensi-
tive powers carries with it the disruption and disinte-
gration of the mind. Since a function independent of
the body is the one feature Aristotle had declared as
proof of immortality, Blaisius claims that mortality is
proved. This proof has Alexandrist features and is not
new. But when Blasius announces that mortality is not
merely probable but must be accepted absolutely we
are in the presence of a new attitude of mind. The
development of this stance is worth examining.

Like his predecessors, Blasius sharply separates
knowledge and belief. To know something, he declares,
is to have arguments based on evidence; to believe
something, knowledge is not necessary, and in the case
of faith must be set aside. Unlike earlier thinkers he
appears to reject the notion of asserting and denying
at the same time with different degrees of certitude.
We cannot have a probable scientific deduction in
conflict with an absolute religious truth. Rather we
must choose one or the other. “When you intend to
support faith which is believed,” contends Blasius, “you
must reject the habit of philosophy which insists on
evidence, and where the reverse occurs, you must
reject the Christian faith.”

The question of course remains: Does Blasius reject
Christian faith absolutely or merely as irrelevant to
philosophy? Perhaps he is insisting with Jandun that
the modes of inquiry proper to faith and reason are
radically different and cannot be combined; each must
pursue a separate path. From Blasius' discussion of the
soul, however, it begins to appear that he favors an
absolute rejection of faith. He introduces the notion
that the soul can be created by spontaneous generation
from waste, as is the case in lower forms of life. The
method of arriving at this conclusion is quite as inter-
esting as the conclusion itself. Discussing the biblical
story of the flood, Blasius points out that all life must
have been destroyed when waters covered the earth
for forty days. “Nor in this matter,” he warns, “should
you believe the tales of women that Noah made an
ark in which he placed all the animals” (Maier, 1949).
Quite the contrary, all human and animal life was
destroyed. Man was created anew from the waste
products and the appropriate constellation of the stars.
It is from this startling discussion that Blasius concludes
that the soul is mortal—produced from matter as other
generable and corruptible things. Now this is not a
probable doctrine of philosophy: Blasius contends that
it must be conceded absolutely.

The suspicions raised by the critique of the Bible
and the absolute assertion of mortality are confirmed
by Blasius' discussion of the origin of religions. The
issue is no longer the status of any particular Christian
belief but the value of Christianity itself. Following
the astrological book De magnis coniunctionibus of
Albumazar (805-85), Blasius explains that the diversity
of religious belief arises from the conjunction of Jupiter
with different planets. These in turn produce the
different religious sects. The Jewish sect, for example,
is produced from the conjunction of Jupiter with
Saturn, while the sect of the Saracens is caused by the
union of Jupiter with Venus. And “from the union of
Jupiter with Mercury the Christian sect is produced.”
Christianity here originates from the same natural


forces which produce the other religions. This extreme
astrological determinism eliminates free choice in reli-
gious matters. Men no longer choose their religions
freely; they are naturally inclined to a particular sect
by the conjunction of the planets.

After some trouble with Church authorities and a
forced recantation, Blasius gave a later lecture in which
he denied these views. In this lecture he warns that
the views of Albumazar are erroneous and false, deny-
ing specifically that the conjunctions of Jupiter with
the other planets produce the various religions. He
insists furthermore that a wise man will supersede the
knowledge of the stars in deciding his own religious
belief. Despite this denial, obviously produced under
pressure from Church authorities, it appears that
Blasius accepts all these philosophical doctrines as
certain. He criticizes religious doctrines on philo-
sophical grounds, attacks biblical miracles, and reverses
the traditional degrees of certitude in religion and
philosophy. For Blasius truth appears to be on the side
of philosophy which claims the privilege of explaining
the origin of religion itself as a natural phenomenon.
Siger's probable philosophical statements are now
transformed into an absolute philosophical certitude,
bowing before religious belief and its representatives
only out of tactical necessity.

The full development of Blasius' doctrines appears
in the sixteenth century, which marks the final libera-
tion of philosophy from its subordination to revelation.
In the Aristotelian tradition most thinkers continued
to maintain sincerely the traditional distinctions be-
tween probable philosophical statements and absolute
religious truth. Some professors in the Italian
universities, however, developed the dramatic shift in
viewpoint already expressed by Blasius. Reacting
quickly to this, the Fifth Lateran Council of 1513
revived the traditional oath of the Parisian masters of
arts; it declared that all discussions of philosophical
positions opposed to faith had to include both a defense
of revelation and a reasoned argument against
heterodox notions. The theologians of the Council
defended orthodoxy with a proclamation of the im-
mortality of the soul as a dogma and the condemnation
of three errors: the unity of the intellect, the mortality
of the soul, and the idea that such doctrines were true
“at least in philosophy.” “Truth does not contradict
truth,” said the theologians, echoing the 1277 condem-
nation. In the works of the professors of philosophy
we do not find the open admission, as the Council
charged, of two contradictory truths. But doubtless
there were some who were guilty of asserting the
absolute truth of philosophy while paying perfunctory
obeisance to the “truth” of revelation. An outstanding
example of this attitude can be found in the works of
Pietro Pomponazzi (1462-1525).

Teaching natural philosophy at Padua, Ferrara, and
Bologna, Pomponazzi summarizes and reshapes the
more radical conclusions of his predecessors in the
Aristotelian tradition. Of the philosophical themes we
have traced Pomponazzi concerns himself primarily
with three: the mortality of the soul, the regularity
and universality of natural laws, and the nature of
religious doctrine. In his immortality treatises—De
immortalitate animae, Apologia,
and Defensorium—he
proves the mortality of the soul. The proof is original
only in the sense that it unites many formerly disparate
elements. With Alexander of Aphrodisias, he insists that
the soul inheres in the body and is forever bound to
its material foundation; the corruption of the material
foundation entails the destruction of the soul. With
Blasius, he finds that no function of the soul can exist
without some relation to bodily powers; for even the
highest function of thought is part of an interlocking
chain of powers based on corruptible matter. With
Scotus, he argues against Thomas Aquinas that the soul
cannot simultaneously be an immaterial substance and
the act of the body; an immaterial substance is separate
and separable from the body while an act is a process
perfecting bodily operations. Since Aristotle had
always defined the soul as the act of the body, we must
hold that it is always bound to the powers it perfects;
hence it is mortal, Pomponazzi concludes.

In the De incantationibus, Pomponazzi discovers
natural causes for “miraculous occurrences.” Cures,
visions, and the raising of the dead are all explained
in three ways: as human inventions, the effects of occult
powers (found in plants, animals, and men), or the
results of the activity of the heavenly Intelligences.
Miracles are reduced to unusual events which only the
trained mind can trace to their natural causes. The
clear conclusion is that there are no miracles produced
by angels or demons because there are no interruptions
of the natural processes of birth, growth, and decay.

After Pomponazzi establishes these doctrines as the
findings of philosophy and natural reason, he applies
the usual distinctions which have been traditional for
three centuries. These are the findings of natural rea-
son, he says, but they must be suspended by faith. The
Church teaches immortality as well as miracles pro-
duced by God, demons, and angels. We must accept
all this as true, rejecting the conclusions of reason.
Although not demonstrable by reason, the truth of faith
is superior to the findings of reason. For God, who is
the creator of nature, may suspend its principles. In
these apologetic statements, Pomponazzi appears to
be very close to Siger, Boethius of Dacia, and Buridan.


Closer examination, however, reveals that he follows
the path of Blasius. Like Jandun, Pomponazzi knows
and lectures on Averroës' prologue to Physics, Book
III. In these lectures, he proclaims in the name of the
Commentator that “truth is the end of philosophy
while the end of the religious lawgiver is neither truth
nor falsehood but to make men good and well-
behaved.” He takes the precaution, as did Jandun, of
associating these views with Averroës, and finally con-
demns them as false. But in his own name in his pub-
lished works there are striking instances of Pompon-
azzi's acceptance of philosophy as absolute truth, and
his discovery of a human origin for religious doctrines.
Immortality, he comes to state, is an invention of
religious lawmakers who proclaim this doctrine “not
caring for truth.” Clearly the truth they do not “care
for” is the doctrine of mortality as proved by philoso-
phy. Demons and angels, which he apparently has
accepted as the Church's teaching, he finds were also
invented by men “who knew very well that they did
not exist.”

Finally, Pomponazzi holds that Christianity is not
the gift of an eternal God but merely the product of
impersonal heavenly forces. These forces, the heavenly
Intelligences, produce life-cycles for all religions, in-
cluding Christianity. In fact, Christianity itself, he
explains, is approaching its death which is why the
Intelligences produce so few “miracles” at the present
time. If the origin of Christianity is temporally condi-
tioned, so are its doctrines. Far from eternal verities,
they are the inventions of religious lawmakers who seek
to control a bestial human nature through the fear of
hell and the hope of heaven. The philosopher who does
not need such restraints, Pomponazzi continues, may
nevertheless understand their purpose and approve of
them for the masses.

These doctrines mark the beginning of the end of
theological dominance in the West. Philosophy is no
longer a collection of probable statements but an abso-
lute truth subjecting all doctrines to its powerful anal-
ysis. It begins to dislodge theology from its position
as queen of the sciences.

If we glance briefly over the history we have dis-
cussed, we can see that the masters in the Faculty of
Arts at Paris initiated a tradition which lasted over
four centuries in the universities of Europe among
those philosophers who were professionally concerned
with Aristotle and his commentators. Refusing to find
or to force agreement between pagan doctrines and
revelation, the Parisian masters raised, in its most ex-
treme form, the problem of the precise relationship
of philosophical inquiry to revealed truth. Moreover
they did this at a time when revealed truth had the
strongest institutional sanctions. The history of the idea
of double truth is thus really the history of the rela-
tionship of philosophy to theology among professional
philosophers in the Aristotelian tradition. By carving
out an independent domain of inquiry for philosophy,
the earlier thinkers, led by Siger, freed philosophy from
the necessity of theological guidance. This made possi-
ble its ultimate escape from religious domination.
Siger, Boethius of Dacia, Jandun, and Buridan all sin-
cerely accepted the one supreme truth of theology.
Yet it was probably to be expected that some thinkers
in this tradition, confronted constantly with the un-
Christian naturalism of Aristotle, would one day pro-
claim the Stagirite's doctrines as the highest truth, and
turn this truth against theology itself.


The text of the 1277 condemnation is found in H. Denifle
and A. Chatelain, Chartularium universitatis pariensus
(Paris, 1889), I, 543-55. See also: W. Bentzendörfer, Die
Lehre von der zweifachen Wahrheit bei Petrus Pomponatius

(Tübingen, 1919). G. Di Napoli, L'Immortalità dell'anima
nel Rinascimento
(Turin, 1963). Pierre Duhem, Système du
Vol. V (Paris, 1954). É. Gilson, “La doctrine de la
double vérité,” Études de philosophie médiévale (Strasbourg,
1921), pp. 51-69; idem, History of Christian Philosophy in
the Middle Ages
(New York, 1955). T. Gregory, “Discussioni
sulla 'doppia verità,'” Cultura e Scuola, 2 (1962), 99-106.
P. O. Kristeller, “Paduan Averroism and Alexandrism in the
Light of Recent Studies,” Atti del XII Congresso Inter-
nazionale di Filosofia,
9 (1960), 147-55. S. MacClintock,
Perversity and Error: Studies on the “Averroist” John of
(Bloomington, Ind., 1956). A. Maier, Studien zur
Naturphilosophie der Spätscholastik,
Vol. I: DieVorläufer
Galileis im 14 Jahrundert
(Rome, 1949), 279-99; Vol. IV:
Metaphysische Hintergrunde der spätscholastischen Natur-
(Rome, 1955), 3-45. A. Maurer, “Between Rea-
son and Faith: Siger of Brabant and Pomponazzi on the
Magic Arts,” Medieval Studies, 18 (1956), 1-18. J. P. Muller,
“Philosophie et foi chez Siger de Brabant: La Théorie de
la double vérité,” Studia anselmiana, 7-8 (1938), 35-50. B.
Nardi, Studi su Pomponazzi (Florence, 1965). A. Pacchi, “Sul
Commento al 'De anima' de G. di Jandun, IV: La Questione
della Doppia Verità,” Rivista critica di storia della filosofia,
15 (1960), 354-75. M. Pine, “Pietro Pomponazzi and the
Problem of Double Truth,” Journal of the History of Ideas,
29 (1968), 163-76. L. Thorndike, A History of Magic and
Experimental Science,
Vol. IV (New York, 1934), 64-79; Vol.
V (New York, 1941), 94-110. F. Van Steenberghen, Siger
de Brabant
(Brussels, 1938); idem, Aristotle in the West
(Louvain, 1955); idem, la Philosophie au XIIIe siècle
(Louvain, 1966).


[See also Astrology; Certainty; Creation; Death and Im-
mortality; Dualism; God.]