AVERROISM. – From the second half of the 13th century to the entire 16th century, those who, in controversies surrounding the thought of Aristotle, gave preference to the commentary of Averroes were called Averroists (averroistae, Averrois sectatores). In the last century, E. Renan, under the name of Averroism, conflated those philosophical doctrines—whether Averroistic or not—that originated from the various and often opposing currents of Arabic Peripateticism. Modern scholars, particularly Mandonnet in his great monograph dedicated to Siger of Brabant and Latin Averroism of the 13th century, were strongly influenced by Renan’s conflation. With the expression “Latin Averroism,” Mandonnet refers to that complex of doctrines that St. Thomas Aquinas combated in his *Summa Contra Gentiles* and which formed the principal object of the condemnation pronounced on March 7, 1277, by the Bishop of Paris. The confusion is further compounded by the fact that Averroism was presented as a heretical movement.
At the beginning of the 13th century, when Aristotelianism spread through the Latin West, ecclesiastical authorities and masters of theology were seriously concerned about the contrast on many points between Aristotelian philosophy and Christian thought. However, the prohibitions of 1210, 1215, and 1231 were insufficient to halt the spread of Aristotelianism; those of 1245 and 1263 likewise failed to expel it from the schools where it had already taken root. This occurred because Peripatetic philosophy satisfied a need. The Latin West possessed a theology but lacked a physics—that is, an organic doctrine of nature, indispensable for understanding the works of Hippocrates, Galen, and other physicians. Aristotelian physics, which was first adopted in the faculty of arts, could not be ignored by the faculty of theology, which one entered only after completing studies in the arts. Only thus can we understand how, after 1230, all Scholastics without exception became Aristotelians, inasmuch as they all broadly accepted Aristotle’s physical framework.
ism, striving to reconcile it through ingenious devices with biblical thought.
Nevertheless, in the development of Scholastic Aristotelianism, we must distinguish three distinct moments or trends.
The first and oldest is what we may call the Augustinian-influenced approach. The doctrine of Avicenna, strongly tinged—like Augustine’s thought—with Neoplatonic reflections, had matured in a climate saturated with religious ideas, which the Muslim philosopher had endeavored to reconcile with Aristotle’s physics and metaphysics. Not only had he sought to preserve the individuality of human consciousness and its immortality—the central pillar of both Christian and Muslim dogma—but in his conception of the world, he made room for miracles, prophecy, and revelation. In particular, his doctrine of the active intellect seemed readily reconcilable with Augustine’s doctrine of divine illumination and the eternal reasons. Even the Stoic-Politian theory of seminal reasons, reaffirmed by the Bishop of Hippo, appeared capable of being seamlessly integrated into Avicenna’s system, for in his view the forms—according to the Aristotelian concept, drawn from the potentiality of matter—emanated from the light of the active intellect. This Neoplatonizing, Augustinian-influenced approach includes Domingo Gundisalvi, William of Auvergne, the early Franciscan doctors, and, in essence, Albert the Great.
It was precisely against this Augustinian-influenced approach that the movement known as Averroism reacted. The Latin translation of Averroes’ commentaries on Aristotle, rendered by Michael Scot with the assistance of the Jew Andrew (mentioned by Roger Bacon in *Compendium studii philosophiae*, ed. J. S. Brewer, p. 472) and perhaps others, became known roughly seventy or eighty years after Avicenna’s philosophical writings. Traces of it begin to appear only in works composed around 1230. Albert the Great, in his *Summa de creaturis*, written twelve years later, cites Averroes numerous times but often misunderstands his thought, which he appears to know only vaguely. John of Rochelle, who died in 1245, was entirely unaware of the characteristic Averroist doctrine of the intellect. It was only after the mid-century that the Averroist commentary began to circulate among scholars. The first extensive and accurate exposition of Averroist doctrine is that of St. Thomas Aquinas in his commentary on the *Sentences* (dist. 17, q. 2, a. 1), likely written at the beginning of 1255. St. Albert informs us that in 1256, at the papal court of Alexander IV in Anagni, he held a disputation “against the errors of Averroes,” and that, by order of the Pope, the treatise *De unitate intellectus contra Averroem* emerged from this disputation—likely revised by its author. A far more precise exposition of Averroes’ doctrine is provided by Albert in his commentary on *De anima*, written around 1260, and in the two treatises *De natura et origine animae* and *De intellectu et intelligibili*. In his discussion of Averroism and in his general interpretation of Aristotelian thought, Albert’s stance differs profoundly from that of Thomas. On many points, the Dominican of Cologne openly opposed his Italian confrere and disciple; indeed, he went so far as to declare that he abhorred the interpretation that Latin doctors gave to Aristotle’s doctrine: *omnino abhorremus doctorum latinum verba* (*De anima*, III, 2, 1), and he did not hesitate to prefer the interpretation of the great Peripatetics, such as Avicenna, Averroes, Alfarabi, and Algazel: *Nos autem, omissis operibus quorundam modernorum, sequentur tantum peripateticorum sententias, et praecipue Avicennae et Averrois et Alpharabi et Algazalis* (*De somno et vigilia*, I, 1, 1; cf. ibid., III, 1, 12). When confronted with the objection that Aristotle’s thought, thus expounded, clashed on grave matters with theological teaching, he frankly acknowledged this opposition and reproached those who *confundunt philosophiam in theologiam*, failing to recognize that theological principles do not align with physical ones.
Thus, in his paraphrases of Aristotle, he avoided any discussion of theological matters: *et ideo de illis in philosophia non possumus disputare* (*Metaphys.*, XI, 3, 7); he declared, *dico quod nihil ad me de Dei miraculis, cum ego de naturalibus disseram* (*De gener. et corr.*, I, 1, 22)—a phrase later repeated verbatim by Siger of Brabant, Peter of Abano, and John of Jandun.
This frank acknowledgment by Albert of the opposition between Peripatetic philosophy (the only one medievals designated by the term “philosophy”) and revealed truth is what modern historians of philosophy term the “doctrine of the double truth.”
Siger of Brabant is called “a disciple of Albert” by Agostino Nifo (*De intellectu*, I, 3, 26), who, in Padua toward the end of the 15th century, still lectured on at least three of the Brabantine Averroist’s now-lost writings. Certainly, not all the theses advanced by Siger were defended by the master of Cologne; yet some characteristic Averroist doctrines undoubtedly appear in Albert’s commentaries.
As we know, the aim pursued by Averroes had been to free the interpretation of Aristotelian thought from the later Neoplatonic accretions of Alfarabi and Avicenna. Especially of the latter, whom Averroes reproaches for having corrupted the pure doctrine of the Stagirite with extraneous concerns. When the Scholastics, already prejudiced in their interpretation of Aristotle by Avicennian exegesis, came into possession of Averroes’ commentary, they perceived the profound contrast between one manner and another of understanding Aristotle. It is therefore no wonder that some masters of the Faculty of Arts, in Paris and Bologna, preferred Averroes’ “Great Commentary” to Avicenna’s interpretation, and, following in its footsteps, proposed to restore to Aristotle his true visage.
These masters were precisely called Averroists. We know the names of a small group of early Averroists: Siger of Brabant, Bernier of Nivelles, and Goswin of La Chapelle, all three masters in Paris, all three canons in Liège, and all three cited together by the Inquisitor of France on 23 November 1276; to these must be added Boethius of Dacia, whose name appears alongside Siger’s in the manuscript of the Bibliothèque Nationale in Paris (Lat. 4391) containing the 219 theses condemned in 1277. Their philosophical activity must have begun to manifest itself a decade before this date.
The principal doctrines of Averroism are as follows:
1) The world is necessary and coeternal with God, who is its first moving cause as the end to which all things tend;
2) The human species is likewise eternal, so that there never was a first man;
3) The power of the First Mover is infinite in duration but finite in intensity and vigor;
4) If there were separate intelligences not assigned to the motion of a heaven, they would be useless;
5) God cannot alter the order of the world;
6) The soul, which is the form of the human body, is a principle of vegetative and sensitive life, endowed with a disposition to unite with the “material” or potential intellect;
7) The potential or possible intellect is an immaterial and separate substance, unique to the entire human species; it is the inmost part of the separate intelligences; hence it cannot be said to be the form of man in the same way as other material forms;
8) The possible intellect is by its nature ordered to know sensible things; hence it must be eternally united to the human species, whose scattered individuals provide it with sensible images or “phantasms,” from which, by a process of abstraction, it draws the concept or “intelligible species.” Although it cannot be said to be the form of the human body in the same way as material forms, it is united to the human “cogitative” faculty by a natural bond that cannot be called accidental, and it can never be thought entirely separate from man;
9) In this process of abstraction, the possible intellect is aided by the agent intellect, which, for some Averroists, is God, and for others, a separate intelligence always in act;
10) The agent intellect unites with the possible intellect, at first only as the efficient cause of the cognitive process and forms the speculative intellect; at the end of this process, it unites with it as form and renders it capable of understanding separate substances in their pure intelligibility. In this perfect union of the possible intellect with the agent intellect consists the supreme perfection of man and the beatitude to which only a few privileged individuals are granted to attain in this life;
11) As a separate substance “which is neither body nor a power in a body,” the human intellect is immortal and eternal *a parte ante* and *a parte post*; mortal, instead, is the vegetative and sensitive soul, which is the specific form of each human individual.
From this summary it is clear that the widespread expression “monopsychism” to denote Averroist doctrine is erroneous; for the soul, according to the Averroists, is multiplied with the number of individuals; the intellect, indeed, is unique to the entire human species, but not to all other beings distinct from man.
The third Aristotelian current in Scholasticism is the Thomistic. The Aquinate, having noted important divergences between the old Aristotelian translation from the Greek and the translation from the Arabic, and even more the proposed interpretations of the text, induced his Flemish confrere, William of Moerbeke, to revise word for word the Greek-Latin version and, where necessary, to produce a new translation perfectly faithful to the Greek text. Thereupon he set about a new literal exposition of Aristotle’s principal works, entirely independent both of Avicenna’s interpretation and of Averroes’. In this way he believed he could combat Averroism on the philological as well as on the philosophical terrain. And Thomas was the most resolute and decisive opponent of Averroism, portrayed by him as absurd from the philosophical point of view and as heresy from the theological. It is doubtless owing to the vigorous critique of the Italian Dominican that Averroism, presented as heresy, drew the attention of the ecclesiastical authorities in Paris, who pronounced against it the condemnation of 1270 and that of 1277.
Yet Averroism was not a heresy; for the Averroists declared that they upheld certain theses, not as true, but as necessary consequences of the principles of Aristotelian philosophy. If these theses conflicted with revealed truths, so much the worse for Aristotle and for those who had striven to make him Christian at all costs and to establish a kind of concordism between Aristotelian philosophy and Christian truth. This is the precise meaning of the so-called “doctrine of the twofold truth.”
Thanks to these declarations, which had a precedent in analogous statements by Albert the Great, the Averroists did not lay down their arms either before the Thomistic critique or before the double Parisian condemnation. It is true that prudence was advisable. And in Bologna Taddeo Alderotti, in his commentary on Ioannitius, written before 1283, refused to resolve the problem of the unity of the intellect, “since there is disagreement between the Church and the philosophers.” But toward the end of the thirteenth century and at the beginning of the fourteenth, the disputes flared up again more vigorously than before, as is shown by the writings of Ramon Lull against the Averroists.
The leading representative of Averroism in the first decades of the fourteenth century was John of Jandun. His *Quaestiones* on *De anima*, on the *Physics*, on *De caelo*, on the *Metaphysics*, on the *Parva naturalia*, and on *De substantia orbis*, by their scope and the many valuable pieces of information they contain, offer us a complete panoramic view of Averroist positions at the beginning of the century. The writings of this companion of Marsilius of Padua enjoyed the widest manuscript diffusion, especially in Italy, and, through the medium of print, until the end of the sixteenth century. Only Averroes’ commentary, among the works of Averroists, had a greater number of editions. The doctrines of John of Jandun inspired Master Taddeo of Parma, who taught in Bologna between 1318 and 1321, and was a colleague of another Averroist, Angelo of Arezzo.
An indirect aid to the Averroists then came from certain theologians who began openly to challenge the Thomistic arguments against A. Thus, for example, Henry of Harclay, master and later chancellor of the University of Oxford (d. 1317), openly reproached those who strive to make Aristotle, the heretic, into a Catholic, and held that, for the Stagirite, the intellective soul cannot be said to be the form of the body. The same view was held by the Carmelite Gerard of Bologna, who considered Averroes to be “the greatest interpreter of Aristotle,” and not “a corrupter of Peripatetic philosophy,” as St Thomas had judged him. Similarly, the Franciscans Peter Auriol and William of Ockham held that it cannot be demonstrated by philosophy that the rational soul is the form of the human body. In turn, another Franciscan, John of Ripatransone, in a lengthy and original exposition of Averroist doctrine (In I Sent., super prol., q. II, cod. Vat. lat. 1082, f. 23v-b-30r), written between 1357 and 1360, held that only Averroes had understood Aristotle. Baconthorp (v.) also vigorously criticized the Thomistic arguments against A., and, having suggested a single way to render the Averroist doctrine of the union of the intellect with man less implausible, was hailed by the Averroists of the late 1400s as “prince of the Averroists.” In the 15th century, Cardinal Bessarion (In calumn. Plat., III, 22) likewise held that Aristotle was well understood by Averroes.
Thomas of Wilton, who had studied at the University of Paris when the teaching of Siger was still echoing there, and who later became chancellor and canon of London, was a resolute supporter of A. in England. At Oxford, no less than at Paris and Bologna, Averroist centres long persisted. From Bologna, A. spread to Florence. Taddeo Alderotti was a Florentine, and at Bologna he certainly had Florentine disciples. Averroist, as we now know, was Guido Cavalcanti, “one of the best laymen in the world and an excellent natural philosopher” (Boccaccio, Dec., VI, 9) and Dante’s first friend. Even in Dante’s thought, clear traces of Averroist doctrines are not lacking.
In the 15th century, Padua became a stronghold of A. If it is necessary to make many reservations about the alleged A. of Peter of Abano (v.), it is nonetheless certain that at Padua Averroes was held in high esteem, since in the chapel of the Cortellieri, attached to the church of the Eremitani, the painter Giusto de’ Menabuoi was commissioned, before 1397, to depict the figure of the Arab philosopher among the patron saints of the order and beside the master Albert of Padua, whereas it is well known that in paintings of Dominican inspiration Averroes was depicted as condemned at the feet of St Thomas. It was precisely an Augustinian, Paul of Venice (v.), who had studied at Oxford, who began to teach in Padua after 1408 a tempered A., endeavouring to reconcile, by careful distinctions, the typically Averroist thesis of the unity of the possible intellect with that which holds the intellective soul to be the “inherent form” or “informant” of the individual human being.
This attempt by Paul of Venice gave rise within A. itself to a particular current, which we may call Sigerian, and which had not a few followers. While most Italian Averroists—such as Gaetano da Thiene, Peter Trapolino, Ludovico Boccadiferro, Marcantonio Zimara, Luca Prossiccio, Marcantonio Passeri known as il Genoa, Francesco Vimercati, Rinaldo Odoni, Gian Paolo Pernumia, and Francesco Piccolomini—remained at the view that the human intellect could only be said to be the “assisting” and not the “informing” form of man, the followers of the Sigerian current granted that, according to Averroes, the intellect is united by a substantial bond to the sensitive soul and, more precisely, to the “cogitative” power, so as to constitute, together with it, “a single soul,” as Dante says with Albert the Great (Purg., XXV, 74), which is the whole informing form of the individual human being and gives man his being as a rational animal. This doctrine, according to the testimony of Agostino Nifo, who was its follower in the early years of his teaching at Padua (1490–98), derives from the Tractatus de intellectu that Siger had written in reply to that of St Thomas and which was still read at Padua, along with other writings of the Brabantine, towards the end of the 15th century. To this doctrine, which Siger had elaborated in his effort to answer the Thomistic arguments against A., there adhered Giovanni Pico della Mirandola, Alessandro Achillini, professor of philosophy and medicine at Bologna from 1484 to 1512, Tiberio Bacilieri, who, after teaching at Bologna and Padua, moved in 1503 to the Studium of Pavia, and Antonio Bernardi of Mirandola, who taught at Bologna (1533–39) and later became bishop of Caserta.
But with Giovanni Pico, friend and correspondent of the Jewish Averroist Elijah del Medigo, Paduan A. began to enter a new phase. He was the first to make use of Simplicius’ commentary on the De anima. Nifo, who discussed with Pico the Sigerian doctrine and the possibility of reconciling the thesis of the unity of the intellect with the individuality of human personality and the immortality of the soul, believed he had found in Simplicius’ commentary confirmation of the Sigerian theory. Yet his knowledge of the Greek commentator’s work was hasty and confused. Nevertheless, other Averroists seized upon the idea and strove to show that Averroes’ commentary agreed almost entirely with that of Simplicius. It was Marcantonio de’ Passeri known as il Genoa who, with great learning and acumen, devoted himself to developing this thesis. He, who taught at Padua from 1517 until his death in 1563, left us a lengthy and learned commentary on the De anima (printed in Venice in 1576; ms. Vat. lat. 4705–7 in a somewhat different arrangement), in which the Simplician exposition is continually cited to confirm the Averroist doctrine. He persists in affirming that the human intellect is the “assisting” and not the “informing” form of man; yet he maintains that it has with the “cogitative” power a natural and essential relation, as an intrinsic and proper operation of man, as Siger thought; so that the union cannot be said to be merely accidental. A disciple of il Genoa, the Paduan Giovanni Fasolo, publishing in 1543 his Latin translation of Simplicius’ commentary on the De anima, declared that whatever is good in the Averroist commentary comes from Simplicius, and in the name of good taste urged that the writings of the Arab, translated into a barbarous and inelegant language, be set aside, and that henceforth only Themistius and Simplicius be studied.
Not all Averroists, however, accepted this invitation. Indeed, Francesco Piccolomini, in his Capitae sententiae Simplicii ex commentariis librorum de anima deprompta, warned against enthusiasm for Simplicius, demonstrating that the Simplician interpretation of Aristotle arose from an attempt to reconcile the Stagirite with Plato, and had nothing to do with the Averroist commentary. Nevertheless, the attempt of Pico and il Genoa, by steering A. into the great Platonic current, preserved its central motive of truth; whereas the Averroists who continued obstinately to repeat the old formulas, and did not feel the breath of new life that blew powerfully around them, spent their days in sterile and barren disputes, soon forgotten along with their writings, which spoke a language that had become incomprehensible.
The decline of A. was also hastened by the new physics and the new astronomy, for the Averroists, more than other Aristotelian schools, were stubborn opponents of the new philosophy of nature.
In the great dispute with Alexandrism, which dominates the entire 16th century, the Averroists were the opponents of Pomponazzi, Porzio, Madio, and Castellani, against whom they polemicized. But the immortality they defended was not that of individual personality. Hence, in practice, they ended up agreeing with their adversaries on this point.
Openly professed from the chair and in works disseminated even “cum privilegio superiorum” and sometimes dedicated to high ecclesiastical dignitaries, by men who incurred no molestations from the inquisitors (the prohibitions in Padua by Bishop Pietro Barozzi and the inquisitor Fra Martino da Lendinara, in 1489, are among the rare cases of excessive zeal), the Averroists enjoyed the most untrammeled freedom ever granted for both teaching and printing. The disappearance of Averroism from the philosophical horizon was due neither to persecutions nor to prohibitions, but to the natural exhaustion of its vitality, without maledictions or regrets, after having exercised an effective action of criticism and control over the other doctrines opposed to II.