“Aquinas and the Arabs: Aquinas’s First Critical Encounter with the Doctrine of Averroes on the Intellect, In 2 Sent. d. 17, q. 2, a. 1,” in Philosophical Psychology in Arabic Thought and the Latin Aristotelianism of the 13th Century, Luis X. López-Farjeat and Jörg Tellkamp, eds. (in press with Vrin, Paris) (29,764 words, in press).

“Aquinas and the Arabs: Aquinas’s First Critical Encounter with the

Doctrines of Avicenna and Averroes on the Intellect, In 2 Sent. d. 17, q. 2, a. 1,”1

Richard C. Taylor

(Uploaded 22 October 2011)

Throughout his entire career as a theologian and philosophical thinker, Thomas Aquinas was deeply concerned with the interpretation of Aristotelian teachings on the nature of the human soul and intellect as provided by Averroes in the latter’s Long Commentary on the De Anima of Aristotle.2  As is well known, Aquinas engaged the reasoning of Latin followers of Averroes as well as that of Averroes himself in his polemical De unitate intellectus contra averroistas written in 1270 by drawing upon arguments already set forth in critical accounts in the Summa contra gentiles (1259-64), the Compendium theologiae (ca. 1265-67), the Quaestiones disputatae de anima (1265-68), the Quaestio Disputata De Spiritualibus Creaturis (1267-68), the Commentary on the De Anima of Aristotle (1267-1268), and the Summa theologiae (1267-1268). However, his first critical engagement with the doctrine of Averroes on the intellect is found in his Scriptum super Sententiis (1252-1257) at book 2, d. 17, q.2, a. 1, entitled, “Whether there is one soul or intellect for all human beings.”3 Posed in this fashion, the question driving his analysis is seen by Aquinas to bear upon the teachings of Theophrastus,  Alexander of Aphrodisias, Themistius, Avicenna, and Ibn Bajjah (Avempace), as well as Averroes,4 since, as Aquinas writes,

nearly all the philosophers after Aristotle are in agreement that the agent intellect and the possible [intellect] differ in substance and that the agent intellect is a certain separate substance both last among the separate intelligences and related to the possible intellect as that by which we understand, as higher intelligences [are related] to the souls of the spheres.5

In forming this view of post-Aristotelian philosophy Aquinas drew primarily upon two philosophical sources: (i) the Long Commentary by Averroes for all the teachings of the other philosophers mentioned above and for the doctrine and arguments of Averroes himself and (ii) the Latin translation of Avicenna’s De Anima for the Persian philosopher’s own teachings on the soul.6  In the present article and the translation in the Appendix, my primarly focus is on the use of Averroes by Aquinas though the important role of Avicenna in the development of the thought of Aquinas on epistemology will also be addressed.

In the first section below I provide an analysis of Aquinas’s accounts of his philosophical predecessors and of their reasoning for their positions together with his critical rejection of their views asserting in various ways that human intellect or intellective soul is one for all human beings.  This will make clear his own impressive depth of understanding of his sources as well as his sophisticated  critical insights into arguments relevant to the formation of his own quite distinct doctrine. I will also indicate important limitations of his understanding of the philosophical teachings of his chief source, Averroes, of which Aquinas was unaware. As we shall see, consideration of those teachings will go far toward saving Averroes from definitive refutation by Aquinas.  In the second section I focus on Aquinas’s exposition of his own teaching on the nature of the intellect or intellective soul and provide an analysis of the arguments and presuppositions underlying his novel account of the multiplicity of individual human intellects and of the multiplication of sets of intelligible species in individual intellects. I then conclude with a summary and some remarks about the importance of the thought of Albertus Magnus, Aquinas’s teacher, who, in dialogue with the texts of Avicenna and Averroes, developed an epistemological scheme which was adopted by Aquinas as the basis of his own understanding of natural human knowing.

1. Aquinas on the Unity of Intellect in “nearly all the philosophers after Aristotle”

Thomas [A]7 begins his solution to the issue of whether there is one intellect or one intellective soul for all human beings by stipulating, first, that he will not consider here views that there exists just one intellect for all reality or that the intellect is nothing but the divine essence and, second, that his main concern will be the unity and diversity of the human rational soul.  While he treats of this issue in Avicenna, Alexander, Theophrastus and Themistius, Ibn Bâjja (Avempace), and Averroes, it is clear that his primary source is the Long Commentary by Averroes and that his chief concern is the challenge posed by the doctrine of intellect set forth in that work.  This is evident [B] in his account of the terminology of intellect: possible intellect, agent intellect and intellect in a positive disposition (intellectus in habitu)8 which is based on this work by Averroes. For his explanation that this is a state consequent upon the attainment of abstracted knowledge which enables the intellect to operate per se,9 Aquinas draws on Averroes who holds the intellect in a positive disposition

to refer to the human being who is the one understanding. It is necessary

to add in the account: insofar as it makes it understand everything in its

own right and when it wishes. For this is the definition of a positive disposition,

namely, that what has a positive disposition understands in virtue of it

what is proper to itself in its own right and when it wishes, without it being the

case that it needs something external in this.10

In contrast, for the Latin Avicenna read by Aquinas, the intellect in habitu or intellect in a positive disposition instead is a disposition of the intellect in virtue of the possession of general principles of the understanding known per se such as that a thing cannot be and not be in the same respect at the same time.11  A similar affinity for the phraseology found in Averroes can also be seen in the initial definitions used by Aquinas for the agent intellect and possible intellect,12 this latter called “material intellect” by both Avicenna and Averroes, a term bequeathed to the tradition by Alexander of Aphrodisias.13   The description of Aquinas coincides broadly with the functions attributed to these intellects by both these thinkers, though Avicenna and Averroes have strongly contrasting differences in the details, as Aquinas will make clear. Here Aquinas describes the possible intellect as “what is in potency for receiving all understood forms.”14  For Avicenna the material intellect is a “pure aptitude” (aptitudo pura)15 for “universal intelligible intentions altogether separate from matter.”16 For Averroes the material intellect is said to have “no nature according to this except the nature of the possibility for receiving intelligible material forms”17 and to be defined as “that which is in potency all the intentions of universal material forms and is not any of the beings in act before it understands any of them,”18 functioning as “the subject of the theoretical intelligibles and of the agent intellect.”19  Regarding the agent intellect, Aquinas writes that this term “names what makes intelligibles in potency to be [intelligibles] in act, as light which makes colors visible in potency to be visible in act.”20  The agent intellect performs that function for both Avicenna and Averroes. However, for Avicenna it is more properly understood as “the intellect in act” which causes the human soul to go from potency to act by giving separate or abstract intelligible form to the soul by way of emanation.21  For Averroes, the agent intellect “makes that intellect which is in potency to understand everything in act”22 and “makes everything intelligible in potency to be intelligible in act after it was in potency,”23 not by emanation but by a genuine abstraction when an imagined intention “is transferred in its being from one order into another.”24 With the clarification of the vocabulary of intellect complete, Aquinas states directly what motivates the discussion of the intellect in this his first theological work.

These two accounts of agent intellect and possible intellect differ in substance and must be rejected according to Aquinas [C] as entailing consequences deeply contrary to the Catholic faith. For while the philosophers hold that the conjoining of human beings to the agent intellect yields ultimate human perfection of knowing and thereby ultimate human happiness, such a view would mean that human salvation would be brought about by a separate intelligence or angel and not by God Himself.  Noting that some Catholic teachers seek to correct and in part accept this view by identifying the agent intellect with God,25 since “by devotion to Him our soul is blessed, which they confirm in virtue of what is written at John 1, 9: He was the true light which illumines all human beings coming into this world,” Aquinas here is content that their view has a certain reasonableness, though he himself rejects that view.26  In the present context, then, his motivation is clearly and expressly theological, though, as we shall see, his engagement with the philosophical tradition will be philosophical grounds.

Aquinas proceeds [D] to his critical analysis of the views of the philosophers on the unity of intellect by considering those of Alexander of Aphrodisias, Ibn Bâjja / Avempace, Avicenna, Theophrastus and Themistius, and finally Averroes, dividing them into three groups.  The first [E-G] is that of Alexander and Ibn Bâjja / Avempace who regard the possible intellect as corruptible with the body. The second [H] is that of Avicenna who holds the possible intellect to be multiplied and distinct in individual human beings, with its subject not the body or a bodily power but the essence of the rational soul itself, and to come into being with the human body but to persist in existence after the death of the body.27 The third view [I-M] is that “the possible intellect is one for all [human beings], which Aquinas subdivides into two: [I] the view of Themistius and Theophrastus with [J] a refutation by Averroes and [K-M] the view of Averroes with [N] a refutation by Aquinas.  Aquinas concludes the Solution with his own views [O-P] which involve accepting principles from Avicenna and Averroes and incoporating them into his own understanding of agent intellect and possible intellect as powers belonging individually to particular  human souls.  However, with the exception of two sentences on the teaching of Avicenna [H], the sole source for Aquinas on these thinkers appears to be the Long Commentary by Averroes.

Alexander of Aphrodisias and Ibn Bâjjah

Following closely the Long Commentary by Averroes, Aquinas argues [E] that Alexander28 held “that the possible intellect is nothing other than a disposition29 which is in human nature for receiving the impressions of the agent intellect and that this is a bodily power consequent upon the human constitution.”30  In the work of Averroes he found the following quotation from the Arabic version of the De intellectu of Alexander.

Since, therefore, from this body, when it is mixed in a certain mixture, something will be generated from the whole mixture such that it is fit for being an instrument of that intellect which is in this mixed thing, since it exists in all the body, and that instrument is also a body, then it will be called the intellect in potency. It is a power made from a mixture which occurred in bodies, [a power] disposed to receive the intellect which is in act.31

For his criticism of Alexander that the possible intellect is intended by Aristotle to be itself receptive of intelligible species and that Aristotle refutes the notion that intelligible forms may be received into a body or a power in a body, Aquinas relies wholly on Averroes’s refutation of Alexander in the Long Commentary.32 Aquinas saw in Averroes himself a great disdain for the materialist view of Alexander where Averroes writes,

A more unthinkable aspect of the opinion of Alexander is that he said that the first dispositions for the intelligibles and for the other later actualities of the soul are things produced from the mixture, not powers produced by an external mover as is well known of the opinion of Aristotle and all the Peripatetics.  For that opinion regarding the apprehensive powers of the soul, / if it is as we have understood it, is false. For from the substance and the nature of the elements there cannot come to be an apprehensive discerning power. For if it were possible that there come to be such powers from their nature and without an external mover, then it would be possible for the final actuality, which is the intelligibles, to be something produced from the substance of their elements, as color and taste come to be. This opinion is similar to the opinion of those who deny agent causes and those who allow only material causes: these are those who speak of chance. Alexander has greater nobility than to believe this, but the questions which were posed to him regarding the material intellect forced him to this [position].33

Here Averroes (i) attacks Alexander’s notion of the receptive material intellect as “an apprehensive discerning power” which arises from a mixture of physical elements.  Averroes later goes on to rail at length (ii) against what he characterizes as Alexander’s impossible notion that somehow the disposition for receptivity called the material intellect might be a disposition somehow distinct from a subject such as a body or a power of a body, saying of Alexander’s account, “I am ashamed of this account and of this fantastic exposition.”34  Futhermore, according to Averroes, (iii) given that a disposition must be in a subject, one must reject “the impossible results [reached] by Alexander, namely, that the subject receiving the intelligible forms is a body made from the elements or a power in a body.”35  It is precisely on these three points that Aquinas refutes the view of Alexander: (i) “no power caused by the commixture of elements is able to know;” (ii) “a disposition is not [itself] receptive but rather something which has been disposed [is receptive];” and (iii) “what is disposed by this disposition is a body or a power in a body, and in such a way that what receives intelligible forms would be a body or a power in a body, which the Philosopher refutes.”36  Thus, both Aquinas and Averroes are in agreement that the possible or material intellect must be an immaterial apprehensive power which is not a body nor in a body nor an epiphenomenon consequent upon a mixture of the elements.37

Averroes was the sole source of knowledge of the epistemology of Ibn Bâjja / Avempace for the Thirteen Century Latin West and Aquinas draws his critique from the Long Commentary by Averroes.  For Ibn Bâjja, writes Aquinas [F], “the possible intellect is nothing but the power of imagination, insofar as it is naturally constituted such that forms which come to be understood in act are [already] in it.”38  This is only a paraphrasing of the remarks of Averroes that Ibn Bâjja,39 “in the literal understanding of his discussion, seems to intend for the material intellect to be the imaginative power inasmuch as it is disposed so that the intentions which are in it may be intelligibles in act and [so] that there is no other power [which is] the subject for intelligibles other than that power.”40  Aquinas finds this impossible for two reasons. First, since “the phantasms … move the possible intellect, as color moves vision, ” the identification of imagination with the possible intellect would impossibly require that the very same thing at the same time be both mover providing the phantasms or images qua imagination and moved qua receptive possible intellect.41  In this he again follows Averroes who writes,

But it is evident that what occurs to him is impossible. For the imagined intentions are what move the intellect, not what are moved. For it is explained that they are such that their relation to the discerning rational power is just as the relation of what is sensed to what senses, not as of what senses to the positive disposition which is sensation. If it were what receives the intelligibles, then the thing would receive itself and the mover would be the moved.42

Second, for Aquinas, insofar as this power is the imagination, it would be employing a determinate organ of the body, the brain, which is impossible since the intelligibles in act can only be received into an immaterial subject. That is, in the language of Averroes, the power of imagination would be a disposition of a power of the soul which is generable and corruptible just as is the individual.43 The definition of the possible or material intellect requires that it be receptive of intelligibles in act abstracted from material things and so must itself be immaterial.44 For Averroes the Material Intellect is a separately existing substance, while for Aquinas it is an immaterial power or disposition of the individual human soul.

Thus, Aquinas rejects the views of both Alexander and Ibn Bâjja for their materialism which entails the perishing of the human possible intellect at death and for their notion of the unity of the agent intellect as one for all human beings. Given that all that would remain of human beings at death is the unique agent intellect in which all shared, he concludes that “this is heretical in the extreme because in this way reward of those deserving after death would be abolished.”45  Averroes also rejected their views, but his concern was not at all eschatological. Rather,  Averroes rejected both because their explanations could not provide an adequate account of the nature of intelligibles in act as immaterial and separate from the constrictive particularity of body.46 Moreover, quite contrary to the view of Aquinas, Averroes, just as al-Fârâbî and Avicenna before him, held the notion common to the Classical Rationalist tradition in Arabic philosophy that there is just one Agent Intellect enabling intellectual understanding for all human beings, though the late Averroes of the Long Commentary distinguished himself from his tradition by asserting the additional existence of one shared Material Intellect for all human knowers.

Avicenna

In the Solution Aquinas found much more to his liking the view of Avicenna [H] that the possible / material intellect belongs to each human being as an individual and immaterial power of the rational soul.  This rational soul comes into existence with the body but does not perish with the death of the body. To this extent, Avicenna’s view is in accord with the Catholic faith, while his view that there is one Agent Intellect for all human beings Aquinas rejected as erroneous.47 From the two mentions of this in the Solution of the article, the extent of the importance of Avicenna to the thought of Aquinas appears less readily evident than it really is.

His appreciation of Avicenna is all the more clear in the response to the third objection. That objection claims that, if there were a plurality of individual human intellects in accord with the number of human bodies, then the understood forms would also be individuated in each human possible intellect. That individuation would make the received form no longer an intelligible in act as an understood universal essence required for knowledge.  Rather, it would be a particular form individuated by the particular human intellect receiving it.  And in that case knowledge of intelligibles would then require that there be another intelligible over that one, and so forth to infinity.48  The individuation occurring in each individual human intellect would be the same as that occurring in the reception of a form by prime matter, with the result that the possible intellect will be no more of a knowing power than is prime matter which does not know forms.  As the objector puts it, “in the case of both they are received as those are and not as are forms taken absolutely. Hence, just as prime matter does not know forms which it receives, so too neither [does] the possible intellect [understand forms which it receives], as it seems.”49  That is, insofar as form is particularized and consequently not intelligible when received into matter, so too form received into a particular human possible / material intellect would also be particularized and not intelligible.

The chief source of these issues raised in this objection are the texts of Averroes who argues that the Material Intellect must be one immaterially separate and shared power since it receives universal forms into itself as subject of intelligibles.  Were it to be a particular power, it would receive forms in accord with its particular nature as diverse particulars. Hence, in order to be receptive of intelligible forms without contracting them to the particularity which would take place were there many individual material intellects, Averroes holds for a single, shared incorporeal Material Intellect as satisfying his concern about particularization.  Averroes writes regarding the reception of universals forms in the Material Intellect,

The reason why that nature is something which discerns and knows while prime matter neither knows nor discerns, is because prime matter receives diverse forms, namely, individual and particular forms, while this [nature] receives universal forms. From this it is apparent that this nature is not a determinate particular nor a body nor a power in a body. For if it were so, then it would receive forms inasmuch as they are diverse and particular; and if it were so, then the forms existing in it would be intelligibles in potency; and thus it would not discern the nature of the forms inasmuch as they are forms, as is the disposition in the case of individual forms, be they spiritual or corporeal. For this reason, if that nature which is called intellect receives forms, it must receive forms by a mode of reception other than that by which those matters receive the forms whose contraction by matter is the determination of prime matter in them.50

Averroes was also motivated by his reflections on the Paraphrase of the De Anima by Themistius51 to posit a single shared Material Intellect out of concern for the unity of scientific or intelligible discourse that makes intersubjective discourse and understanding possible. He writes,

That way in which we posited the being of the material intellect solves all the questions resulting from our holding that the intellect is one and many. For if the thing understood in me and in you were one in every way, it would happen that when I would know some intelligible, you would also know it, and many other impossible things [would also follow]. If we assert it to be many, then it would happen that the thing understood in me and in you would be one in species and two in individual [number]. In this way the thing understood will have a thing understood and so it proceeds into infinity. Thus, it will be impossible for a student to learn from a teacher unless the knowledge which is in the teacher is a power generating and creating the knowledge which is in the student, in the way in which one fire generates another 412} fire similar to it in species, which is impossible. That what is known is the same in the teacher and the student in this way caused Plato to believe that learning is recollection. Since, then, we asserted that the intelligible thing which is in me and in you is many in subject insofar as it is true, namely, the forms of the imagination, and one in the subject in virtue of which it is an existing intellect (namely, the material [intellect]), those questions are completely resolved.52

In responding to the third objection, Aquinas refuses to accept the analysis of Averroes and follows Avicenna53 in holding that the species or form as understood can be considered either with regard to the being it has of its own nature in a human intellect whereby it has “singular being,” or insofar as it is a likeness of the thing understood whereby it “leads to knowledge of it, and on the basis of this part it has universality.” That is, the understood form or intelligible species is a likeness not insofar as it is of a particular thing but “according to the nature in which it agrees with others of its species.” For Aquinas, as a representation of the nature or kind of the thing experienced, the intelligible species is the foundation for the formation of the universal in the intellect.  Contrary to the view of Averroes for whom particularity of subject necessarily involves the particularization of what is received into a particular subject and, consequently, the loss of intelligible being, Aquinas holds that the reception of the intelligible species as a likeness of the nature does not involve the contraction of the received intelligible species into particularity or singularity.  This is simply because matter is the cause of this particularization in concrete things of the world, while in the case of human intellectual understanding the receiving subject is immaterial.  The received intelligible form or species in a singular human intellect is indeed in a singular receptive subject. But insofar as the subject is immaterial, the received intelligible form or species as a likeness representing the nature of the thing understood is not contracted to particularity or transformed into an intelligible in potency, as Averroes holds.  As is evident in the case of separate substances as immaterial intelligences, an intelligible form or species may be individuated insofar as it belongs to its immaterial subject, “But that species is individuated through the individuation of the intellect and, consequently, it does not lose intelligible being in act.” That is, the intelligible species is in or belongs to the individual intellect but that does not make it no longer an intelligible in act because it is received immaterially, into an immaterial subject. The concern with particularization is a false one for Aquinas, “because the mode of individuation through intellect is other than [the mode of individuation] through prime matter.” The presence of intelligible species belonging individually to a plurality of human intellects does not multiply the nature of the thing understood by means of the intelligible species since it is the nature in the thing which is the object of knowledge, not the intelligible species in the intellect.54

For his argument here Aquinas is drawing on Avicenna’s Metaphysics, book 5, chapters 1 and 2.  There Avicenna argues for this plurality of individual human intellects.  In the Latin version of the text at the end of chapter 1, we find,

This form . . . , although it is universal with respect to individuals, nevertheless, with respect to the singular soul in which it is impressed, it is individual, for it is one of the forms which are in the intellect.  And because singular souls are many in number, then in the way in which they are particulars they themselves will have a different universal notion.55

That is, the intelligible notion exists in the intellects of a plurality of individual human beings without losing its intelligibility.  For Avicenna the intelligible comes to be in the soul’s apprehension and its universality is due to its relation to a plurality of individuals.56 The understood intelligible or species, then, has according to Avicenna precisely the two modes of consideration of which Aquinas speaks in the response to the third objection, consideration insofar as it is an understood intelligible possessed by an individual human intellect and consideration insofar as it is a universal intelligible in relation to the many particulars of the world.  What is more, we can see in book 5, chapter 2, of Avicenna’s Metaphysics the foundations for the teaching of Aquinas that intelligible species are representative of and derived from the natures of particular things.  The Latin version of Avicenna has

Therefore, when we say that the universal nature has being in these sensibles, we do not understand that from the fact that it is universal, namely, according to this mode of universality, but rather we understand that the nature to which universality accrues has being in these determinate particulars.57

Still, just as Aquinas could not accept the views of Averroes on the separation of possible /material intellect, he likewise could not accept the notion common to Avicenna and the Arabic tradition of one separate Agent Intellect shared by all human beings.  Avicenna held that what is most characteristic of human beings is to form universal intelligible intentions altogether separate from matter.58  But he was acutely aware of the problem of a suitable subject for intelligibles in act and asserted that it is inappropriate for the subject to be a body or something dependent upon a body.  Properly speaking, intelligibles in act themselves should not be thought to have place; rather, they have place only insofar as they are in some way conjoined with a body.59 For, were intelligibles literally to exist in a body having place, they could not then be intelligibles.60  While human formation of images in the imagination subsequent to sense perception is necessary, the formation of immaterial intelligibles in the soul can come about only thanks to a conjoining with the Agent Intellect.61  This Agent Intellect in a way gives intelligibles to the soul, not by a changing, transforming or transferring of imagined forms in the imagination into intelligible forms in the human intellect, but rather by emanating (emanet, yufîḍa) the immaterial intelligible forms to the soul when the soul  has been suitably prepared for reception through sense perception and the workings of the internal sense powers.62  Human learning of intelligibles, then, is seeking after complete conjoining with the Agent Intellect to obtain this emanation of forms to the soul. These intelligibles, however, do not remain in the soul but rather the soul comes to possess the acquired intellect whereby it can at will conjoin again with the Agent Intellect and again receive the emanation of the intelligibles.63  For Avicenna the intelligibles are present to individual human intellects only when human rational souls are conjoined with the Agent Intellect.

To the concerns of Averroes for whom the intelligibles in act play a role in necessitating the existence of a single shared Material Intellect Aquinas responds in the response to the third objection, as indicated above.  Again, for Aquinas there is a likeness in each individual human intellect by means of which the nature of the particular thing understood is known, the nature in which other particular things of that species share.64  This, however, is a very different teaching from those of Avicenna and Averroes. For Aquinas the objects of knowledge are the natures of things of the world and not properly the unity of forms in the separate Agent Intellect (Avicenna) or the unity of abstracted forms in the separate Material Intellect (Averroes). In this way Aquinas accepts the doctrine of Averroes on the abstraction of intelligibles from sensory experience, while rejecting Avicenna’s notion that intelligibles emanate from the transcendent Agent Intellect; and Aquinas accepts the assertion by Avicenna that intelligibles can be apprehended and understood in individual human possible or material intellects, while rejecting the assertion by Averroes of a single shared Material Intellect.

In responding to the second concern of the objection,  that singularity or particularity is the key stumbling block to intelligibility, Aquinas responds again by rejecting the notion in Averroes that knowledge requires immediate reference to one common thesaurus of forms in the Material Intellect as objects of knowledge.  He does so by appealing to the nature of self-knowledge in immaterial separate intelligences.  These entities are purely intellectual beings which are both intelligible as immaterial forms and intelligent as forms existing in act separate from matter.  Yet the singularity of each of these does not entail that each exists only as intelligible in potency.  Hence, in these or in human intellects an understood “species is individuated through the individuation of the intellect”65 without the loss of being as an intelligible.  Similarly then, argues Aquinas, the same is the case with my own intellectual understanding insofar “as I understand that I understand, although my understanding is a certain singular operation.” He then concludes that “It is also evident in itself that the second unacceptable consequence does not follow, because the mode of individuation through intellect is other than [the mode of individuation] through prime matter.”66  That is, individuation through prime matter involves the contraction of the form in a genuine hylomorphism with the entailed individuation of any received form as a determinate particular thing; individuation through intellect, however, involves a reception of intelligible species which remain intelligible in the particular human intellect which is their subject.  The intelligible species of Aquinas, then, are neither the unique intelligibles in act themselves of Avicenna ontologically located in the unique Agent Intellect nor the abstracted intelligibles in act themselves of Averroes ontologically located in the unique Material Intellect. Rather, for Aquinas the intelligible species is a likeness representative of the nature of a thing as that by which the nature is understood.

Theophastus and Themistius

Theophrastus and Themistius, according to Aquinas [I], held for the unity of all intelligibles in a possible intellect which is one for all human beings.67 Here Aquinas follows Averroes closely in recounting the teachings of these Greek thinkers and sets out portions of Averroes’s critique of their views.

In defining the intellect in a positive disposition or intellect in habitu at the beginning of his Solution in this article, Aquinas characterizes it as the “formal” intellect which comes to be “when the possible intellect already has been perfected by the intelligible species so that it is able to operate [in its own right].”68 That is, the intellect in a positive disposition, in the actualized state of knowing also called the theoretical intellect, is realized in a human being as intellectual understanding when the actualizing agent intellect and the receptive possible intellect are conjoined with the human knower.  A sign that these intellects are conjoined to us is “that  the action of the intellect which is in our power pertains to the intellect in a positive disposition.  Therefore, since to abstract species from phantasms is in our power, it is necessary that the agent intellect belong to the intellect in a positive disposition as its form.”69  They are motivated to present this account, writes Aquinas, by the fact that the possible intellect “is not a determinate particular (hoc aliquid) nor a power in a body,  and consequently it is eternal.”70  That is, the possible intellect has to be an immaterial nature which is receptive of all intelligibles without particularizing or individualizing them as it must if it were a determinate particular or a power in a body.  As such, the possible intellect on this account can only be one and must constitute a unique species of entity in itself since it must contain all the intelligibles in act which have been abstracted and which constitute a single collection of intelligibles shared by all human knowers.  Further, as noted above, insofar as it is immaterial the possible intellect on this account must be eternal, as also is the agent intellect, and so too must be the intellect in a positive disposition or theoretical intelligibles as effect of the eternal agent intellect and possible intellect.71  From this it follows that “the understood species are eternal.”  Though on this account the objects of understanding are eternal, the natural human experience of intermittent understanding is to be explained as a consequence of intermittent conjoining of the agent and possible intellects.72

Themistius held that there is a single Productive or Agent Intellect which comes to be present in human soul and to organize the possible intellect and human experiences through an abstraction of intelligibles from worldly experience as preserved in the human imaginative power.   Themistius himself says,

There is no need to be puzzled if we who are combined from the potential and the actual [intellects] are referred back to one productive intellect, and that what it is to be each of us is derived from that single [intellect]. Where otherwise do the notions that are shared (koinai ennoiai) come from? Where is the untaught and identical understanding of the primary definitions and primary axioms derived from? For we would not understand one another unless there were a single intellect that we all shared.73

That shared intellect is the Productive or Agent intellect which is eternal and which realizes intelligibles in act by sharing its abstractive power with the individual human intellect (called “actual intellect” by Themistius) which comes to have understanding, that is, comes to be the intellect in a positive disposition, through its role in and connection with the receptive possible or material intellect where all abstracted intelligibles are shared.74

Averroes, however, refutes this view, writes Aquinas [J], “because it would follow that the forms of natural things which are understood would exist from eternity without matter and outside the soul,” a form of Platonism.75 Further, on this account the forms or species of natural things are not related to the possible intellect as what is responsible for its information; rather, the form of the possible or material intellect is the Agent Intellect. Such a view allows too little a role for the abstraction of intelligibles from experience and reveals itself as a forming of the possible intellect directly by the Agent Intellect. Moreover, there would be no difference between one human being and another here, since each soul has the same initial disposition of receptivity of the possible intellect and each soul has the same ultimate realization in the intellect in a positive disposition, that is, in the attainment of the theoretical intellect. As a consequence, writes Aquinas, “there would be one being and one operation for all human beings, which is impossible.”76 All of these remarks by Aquinas are drawn from the texts of Averroes.

Averroes

Aquinas accurately describes the view of Averroes [K] saying that “the agent intellect as well as the possible [intellect] is eternal and one in all [human beings], but the intelligible species are not eternal,”77 if we understand by “intelligible species” the perishable forms in the mortal theoretical intellect belonging to the particular human being.  Aquinas then adds, “He also holds that the agent intellect is not related to the possible [intellect] as its form but as a craftsman to matter and [that] the understood species abstracted from phantasms are as form of the possible intellect [and that] from both of these there comes to be the intellect in a positive disposition.”78  Aquinas correctly recounts the teaching of Averroes that the Agent Intellect is not related to the Material Intellect in such a way that the Agent Intellect provides out of itself alone the intelligibles received by the Material Intellect.  Rather, for Averroes the intelligible content of intellectual understanding comes from sensation and interior processing by imagination, cogitation and memory.79  This is a teaching which Aquinas takes over as his own from Averroes. However, here Aquinas misreads the text of Averroes and the meaning of his metaphor. Instead of characterizing the agent intellect as craftsman or artist, Averroes speaks of art and artistry and denies that the metaphor properly obtains.  This is because

art imposes the form on the whole matter without it being the case that there was something of the intention of the form existing in the matter before the artistry has made it. It is not so in the case of the intellect, for if it were so in the case of the intellect, then a human being would not need sense or imagination for apprehending intelligibles.80

For Averroes sense and imagination are needed to supply imagined intentions or intelligibles in potency which the Agent Intellect separates from matter, abstracting and transferring the intention from the mode of being of an imagined intention to the mode of being of an intention intelligible in act now received into the Material Intellect.81  As Averroes puts it,

to abstract is nothing other than to make imagined intentions intelligible in act after they were [intelligible] in potency. But to understand is nothing other than to receive these intentions.82

Hence, on this much Averroes and Aquinas are in agreement: the content of human intellectual understanding arises not from the agent intellect itself but rather through separating abstractive processes of sense perception, imagination, cogitation, and intellection founded in experience of things of the world and initiated by living human beings who are existing composites of soul and body.83 As we shall see, however, they disagree on two notions which have decisive ramifications for their teachings: (i) the manner in which the possible / material intellect and the agent intellect are in the soul84 and (ii) the nature of the intelligibles in act.85

To escape the problems of the account of Themistius, writes Aquinas [L], Averroes proposed that the intelligibles be understood as having a twofold subject,

one in which it has material being, namely the very phantasms which are in the imagination, and according to this being those species are not eternal; and another [subject] in which it has immaterial being, namely the possible intellect, and according to this subject they do not have the characteristic of being generable and corruptible.86

Aquinas, however, finds this without value and charges that, since the species or form in a  particular human being’s imagination is not the same in number as the species or form existing in the possible intellect, the result is that the intelligible in act can exist only in the eternal separate possible intellect (scil., the Material Intellect of Averroes) apart from the perishable particular human being whose imagination provides the image or intelligible in potency for abstraction. This would then entail that particular human beings would not have intellectual understanding.  Alternatively, it could be argued that the intelligibles in act are eternal in their own right but that would disconnect the intelligibles in act from the images or phantasms apprehended through sense perception by human beings and would be “contrary to the intention and words of the Philosopher.”87 For the agent intellect and possible intellect were asserted to exist to account for the knowledge of intelligibles in act evident in human knowers subsequent to experience of the world. Intellectual understanding cannot properly be separated from human beings whose evident knowledge prompted the discussion of these issues in the first place.

Aquinas then [M] outlines the explanation of Averroes as to how there can be a plurality of distinct human knowers when there is one possible / material intellect. He rightly reports that according to Averroes,

the understood species is related to the possible intellect in some way as form to matter and because of that somehow one complete thing is made from them. [Consequently, in this the possible intellect’s] conjunction with us is through that which is formal in the mentioned conjunction, namely, through the understood species, which he says is the phantasm in us as one subject and the possible intellect itself as the other [subject]88

That is, insofar as human beings by way of the imagined intentions provide the formal content to the receptive possible intellect, the possible intellect can be said to be informed with the forms or natures of things of the world thanks to the abstractive power of the agent intellect.  Here the imagined intention or phantasm is the subject of truth or cause of the formal reality of the abstracted intelligible, an intention or phantasm provided by a particular human being. To this extent the truth of the intelligible in act is grounded in the imagination of the human being.  When this abstraction takes place, recounts Aquinas, Averroes asserts the human being also to be conjoined in intellectual understanding to the possible intellect where the intelligibles in act have the Material / possible Intellect as the subject in which they are existent as intelligibles in act.  In this way, since different human beings have different experiences and different intentions or phantasms in their imaginations, the possible intellect’s conjunction to each is unique in that it takes place only through particular human imaginative powers.  This then allows that intellect in human beings is in one way corruptible and in another incorruptible.  Intellect in human beings is corruptible through the intentions or phantasms existing in the corruptible bodily power of imagination; but it is incorruptible insofar as the abstracted intelligible in act has as its subject the Material / possible Intellect which is incorruptible as immaterial.  Although Averroes makes no mention of it in the context of these discussions, the consequence for him is that there is no personal human immortality since the only things persisting of particular human existence at the death of the human body are intelligibles in act formed in the eternal Material / possible Intellect thanks to the contributions of imagined intentions or phantasms.89  There are no human souls existing in an afterlife or unearthly existence.  However, it is not at all surprising that this point is stressed by Aquinas when he writes, “Hence, it follows also from this that there would remain no diversity of souls after the corruption of bodies.”90  This explication by Aquinas is a reasonably accurate account of the views of Averroes on perishable human nature and the imperishable possible or Material Intellect.

Aquinas, however, describes [N] this account as frivolous with three arguments.

First, [it is frivolous] because, as was said, the species which is the form of the possible intellect is not the same in number in the phantasm as in the subject, but rather, it is a likeness of that. Hence, it follows that the possible intellect is in no way conjoined with us, and so we will not understand through it.91

That is, insofar as it is not the same form in number in the possible intellect and in the imagined intention or phantasm in the human being but instead in the intellect it is only a likeness of that form now as intelligible in act, then the individual human being is not conjoined to the possible intellect through the imagined intention or phantasm and, consequently, the human being is not understanding the intelligible in act.  From this remark it is clear that the only way this concern can be met satisfactorily for Aquinas is if the material / possible intellect is intrinsically present in the individual human being.

It is also frivolous, according to Aquinas, because human beings could not be located in a determinate species as rational animals according to substance if human beings were to have intellect only through conjunction with the separate possible intellect that takes place some interval of time after birth.  If human beings are essentially rational animals, then the power of intellect be must intrinsically present in each from childhood and cannot be something that acrues to the animal by a conjunction with separate intellect at some significantly later time in life.  Intellectuality must be in the “first perfection and substantial being” of a human being and not merely a “second perfection.”  Were the latter the case,  human beings would have the power of intellectual understanding only as an accident subsequent to substantial being, not as an intrinsic specific difference.  If human beings are to be essentially rational and intellectual, again, intellect must in some fashion be essentially present in the soul per se and not something separate and merely accidentally associated with the animal called human.  Averroes holds that the particular human being’s apprehended form in the imagination or cogitative power called intention or species functions as a medium linking the particular human knower with the Material Intellect in that those intentions or species have two subjects, one the human imaginative power and the other the possible / Material Intellect.  But this would at best mean that the intellectual understanding taking place in the separate intellect is somehow accidentally associated with the particular human being’s imaginative power, for Aquinas.  And that is insufficient to support the view that human beings are essentially rational animals who understand intelligibles in act.92  On the view of Aquinas what is required here is that the power called possible or material intellect be intrinsically present in each human being, not separately existent outside the human soul as Averroes has it with his view that the Material Intellect is a substance in its own right.93

The third reason for the frivolousness of the account of Averroes according to Aquinas is based on the notion that an operation of soul must arise from a potency or power in the soul.  No operation belonging to the soul takes place solely on the basis of an extrinsic object. For a human being to see a stone, for example, that human being must possess the power of vision.  The actuality of vision cannot be given to the human being from the stone, the object.  Similarly, the power of intellectual understanding must be a power essentially intrinsic to a human being if that human being is to understand.  The object of understanding alone cannot be a cause of the actuality of understanding unless there is a preexisting power of understanding in the soul intrinsically.  Hence, Aquinas writes,

If . . .  the intellect is conjoined with us only through the fact that the understood species in some way has a subject in us, it follows that this human being, namely Socrates, does not understand but rather that the separate intellect understands these things which which [a human being] imagines.94

That is, the fact that human beings themselves provide forms or intentions in the imagination which prompt conjunction and intellectual understanding does not indicate intellectual understanding on the part of human beings but rather only understanding on the part of the separate intellect.  Unless the power of intellect is intrinsic to human beings, human beings cannot properly be essentially rational or have intellectual understanding. What is required is that the separate Material Intellect and Agent Intellect posited by Averroes be intrinsically present in the human soul.

For clarity sake, the problems which Aquinas raises can be listed as four:

1. If the intelligible in act can exist only in the separate possible intellect apart from human beings, then the result will be that human beings will not have intellectual understanding.

2. If the intelligible in act is in the separate possible intellect alone and only a likeness of that intelligible is in the human being, the human individual is not conjoined with the intellect in intellectual understanding and instead only has an apprehension of a likeness.

3. If human beings are to be essentially intelligent, again, the possible intellect must in some fashion be present in the soul per se and not merely accidentally associated with the animal called human.

4. If human beings themselves provide forms or intentions in the imagination which prompt conjunction and intellectual understanding, this does not entail intellectual understanding on the part of human beings but rather only understanding on the part of the separate intellect.

Set forth in this way, it is clear that all four of these critical concerns can be only be satisfied in one and the same way: intellectual understanding and intellect must be in human beings.  As I explain elsewhere,95 this is precisely what can be found in the Long Commentary if one studies the text of Averroes with an eye to his use of the work of his predecessors in the Greek and Arabic traditions and to the text and issues in the De Anima itself, without being prejudiced by the later reading of Averroes by Aquinas.

In four passages of the Long Commentary Averroes repeats precisely that the agent intellect and the material intellect should be understood to be “in the soul”96 in accord with Aristotle’s De Anima 3.5, 430a13-14, which indicates that potential and actualizing powers of mind must be in the soul (ἐν τῇ ψυχῇ).  Averroes also saw this teaching in Alexander and Themistius.97 In the Long Commentary Averroes continues with even greater frequency and emphasis than he had in his Short Commentary and in the Middle Commentary to say that the agent intellect is “form for us.”98 This is most evident in a passage in which he stresses that the agent intellect is necessarily “form in us” and that intellectual understanding is a proper activity for human beings as intellectual.  As such, the agent intellect is necessarily intrinsic and essential to the nature of human beings as rational and intellectually understanding entities.

For, because that in virtue of which something carries out its proper activity is the form, while we carry out {500} our proper activity in virtue of the agent intellect, it is necessary that the agent intellect be form in us. . . . [I]t is necessary that a human being understand all the intelligibles through the intellect proper to him and that he carry out the activity proper to him in regard to all beings, just as he understands by his proper intellection all the beings through the intellect in a positive disposition (intellectus in habitu), when it has been conjoined with forms of the imagination.99

Averroes also stresses that the activities of abstraction and intellectual understanding take place by our will and so properly belong to willing human beings.  He writes,

The intellect existing in us has two activities insofar as it is ascribed to us, one

of the genus of affection, namely, understanding, and the other of the genus of activity, namely, to extract forms and denude them of matters, which is nothing but making them intelligible in act after they were such in potency. [Hence] it is evident that, after we have possessed the intellect which is in a positive disposition (intellectus in habitu), it is in our will to understand any intelligible we wish and to extract any form we wish.100

The notion of agent intellect as transcendent and yet also necessarily intrinsic Averroes found in Alexander, Themistius and Aristotle. The notion that the intellect is ours, because we employ it when we wish or will to do so, he found in Themistius and Aristotle.101 This conception of intellect as both substantially transcendent and yet necessarily present “in the soul” as an intrinsic formal cause I have elsewhere termed “Aristotelian participation,” since the separate intellects themselves on this account are reasoned to be intrinsically present in human beings for their voluntary use while also being substantially distinct and transcendent.102 It is not Platonic since it does not involve a likeness or diminished and imperfect representation of the separate intellects to be in the soul but rather, again, the agent intellect and the possible / material intellect themselves must be “in the soul” as Aristotle himself writes at De Anima 3.5, 430a13-14. That such a view is perhaps not far from contemporary understandings of Aristotle’s De Anima can be seen in Miles Burnyeat’s 2008 Aquinas lecture entitled, “Aristotle’s Divine Mind,” where Burnyeat insists that in Aristotle our human intellect cannot do without the presence of agent intellect which he also identifies with God following Alexander. Burnyeat writes, “Our mortal intellect needs an immortal intellect to achieve its goal of understanding.”103 Nevertheless, this notion which in the special case of human intellectual understanding allows for the curious notion that one substance can be intrinsically present in another substance was not at all recognized by Aquinas who himself uses Averroes’s own argument for the intrinsic presence of intellect to the soul to insist that possible intellect and agent intellect must be powers intrinsic to every human soul, not transcendent.104

Averroes believed that he was compelled to this account by the multiple philosophical issues such as key concerns about the nature of intellectual understanding, the nature of intelligibles in act, the reality of shared common human discourse and scientific understanding, and many more.  The final account he provides in his Long Commentary goes far in dealing with the four problems arised by Aquinas which I listed above. The first of these is resolved precisely by his locating the Material Intellect “in the soul.”  The second is resolved with the same doctrine of participation which holds for the joining of the human soul with the Material Intellect in the apprehension of genuine intelligibles in act existing in the Material Intellect subsequent to abstraction and transference from the mode of being of particular intentions or what Aquinas calls phantasms.  To this extent the doctrine of Averroes has rightly been understood to entail a certain kind of realism of intelligibles in act.105 The third is also resolved by the presence of the intellect in the soul insofar as the human soul has in it primary propositions of understanding, e.g., that a thing both cannot be and not be in the same respect and other such general propositions of thought,  from the Agent Intellect which it can use as tools for bringing about the actuality of the presence of the separate intellects in the soul. Averroes himself raises the issue of whether we “are called human beings equivocally”106 if we do not ourselves have intellectual understanding. But he finds the issue sufficiently resolved by asserting that human beings have a natural disposition and affiliation, a potency, for the presence of the separate intellects to be in the soul, together with the primary propositions from the Agent Intellect.  The development of intellect in a particular human being depends on the voluntary effort of individuals at understanding.107 The fourth problem is also resolved by the presence of separate intellect “in the soul.” For if the soul has a natural disposition and potency for linking with the separate intellects, then understanding of intelligibles in act takes place during that linking with the Material Intellect, not unlike the account of Avicenna regarding the Agent Intellect.108

2. Aquinas’s Own Doctrine of Intellect in In 2 Sent d. 17, q. 2, a. 1

Aquinas himself109 chose to follow Avicenna [O] in the view that the possible intellect comes into being in each individual with the body, is multiplied in different human beings as individual for each, and does not perish with the death of the body. However, he declines to follow Avicenna’s conception of the separate Agent Intellect and instead adds that it is not improbable that the agent intellect must also be intrinsically present individually in each human being since that is required for the natural operation of intellectual understanding belonging to the human soul. His following remark indicating that this “follows if there is held to be one agent intellect, be it called God or intelligence” is surely meant as a criticism of those who would hold that God is the agent intellect, though he couches it in more general terms.110 The unstated implication is that those who hold for one agent intellect will also have to hold that the transcendent agent intellect or God will have to be intrinsically present in the human soul as a natural operation, something unthinkable in doctrine of natural knowing for Aquinas.111 In this last section of his Solution in this article Aquinas also argues that the agent intellect and the possible intellect, though powers of the soul constituting what together make up the general human intellectual power, must be understood as two diverse powers of the soul. For this distinction of powers in the soul Aquinas draws directly on Averroes’s distinction of the separate intellects. Averroes writes,

Hence, in view of our having asserted that the relation of the imagined intentions 439} to the material intellect is just as the relation of the sensibles to the senses (as Aristotle will say later), it is necessary to suppose that there is another mover which makes [the intentions] move the material intellect in act, and this is nothing but to make [the intentions] intelligible in act by separating them from matter. Because this intention, which forces the assertion of an agent intellect different from the material intellect and different from the forms of things which the material intellect apprehends, is similar to the intention on account of which sight needs light, in view of the fact that the agent and the recipient are different from light. . . .112

Nevertheless, in spite of his arguments, Aquinas [P] makes it clear that he is well aware that “how [the possible intellect and the agent intellect] could be rooted in one substance is difficult to see” since the receptivity of the possible intellect and the actuality of the agent intellect would mean that contrary powers related to the same object would exist in the soul.113  His response to this is that these are distinct powers though they are related in their separate roles in the soul. For the power of soul called agent intellect as “an intellectual light in act” is “a power by which [the soul] makes sensible species to be intelligible [species] in act” by separation or abstraction of the intelligible, while the power of soul called possible intellect is “a power by which it is in potency for being made in the act of determinate knowing brought about by a sensible thing's species made intelligible in act.”114

Here Aquinas displays his famous doctrine of intelligible species as what he will later call representationes and rationes of the natures of things, wherein the object of human intellectual understanding of things of the natural world is the nature as specific difference in the things.115  In this the views of Aquinas and Averroes different substantially.  For Averroes, although intelligibles in act are derived by way of abstraction and transference from imagined intentions or phantasms in the human imagination, he regards the separated intelligibles in act ontologically present in the Material Intellect to be the proper object of human scientific understanding.  This is a view he only came to express fully in his Long Commentary with the establishment of his conception of the Material Intellect as a shared source of intelligibles for all human knowers. In his Short and Middle Commentaries Averroes held for a plurality of individual human material or possible intellects and a very different conception of itelligibles in act.116  In the Long Commentary, however,  he chose to follow Themistius for several reasons which I have discussed elsewhere.117 The most important motivating considerations Averroes discovered in Themistius were (1) the needed for a shared and unique set of intelligibles for the unity of human discourse and for the unity of intellectual understanding, since these presuppose common referents, and (2) the need that intelligibles in act be immaterially existing realities in an immaterial subject.  However, in his late treatise On the unity of the intellect against the Averrroists, Aquinas recognized this and remarked that Averroes had somehow inadvertantly fallen into a form of Platonism in his doctrine of the intellect.118 For Avicenna, as we have seen, intelligibles are described as coming to be in a plurality of human receptive intellects by emanation (fayḍ) from the separate Agent Intellect or by a conjoining (ittiṣâl) with the separate Agent Intellect. Aquinas rejected this role for a transcendent Agent Intellect and embraced with abstractionist account of Averroes, while holding firmly that agent intellect and material / possible intellect are powers of the human soul. And, we have seen, Avicenna appears to have provided some valuable inspiration for Aquinas’ doctrine of intelligible species with texts affirming the natures of things are the bases for universals in the soul.119

3. Conclusion

In publication in 1994, the late Edward P. Mahoney remarked that in this article of the Commentary on the Sentences, “Aquinas … presents the basic analysis of Averroes that he will consistently maintain in his subsequent writings.”120  That statement does prove to be correct, for the way in which Averroes is understood and misunderstood by Aquinas continues to be reflected in later works in which Aquinas deals with issues of intellect and the meaning of the arguments and statements of Averroes.  What has been seen here is that Averroes had found grounds for his understanding of the extrinsic transcendence and the formal immanence of intellect with respect to the human soul in works by Alexander and Themistius and also in Aristotle’s De Anima itself.  However, it is noteworthy that there is some evidence that Aquinas was aware of the proper understanding of this teaching on the part of Averroes.  This is clear in his analysis of ultimate human happiness and beatitude in seeing God face-to-face in the afterlife found later in Book IV of his Commentary on the Sentences where he accepts the model of Averroes, which I have called “Aristotelian participation” above, as suitable for explicating this theological teaching central to Christian faith.121  At In 4 Sent., d. 49, q.2, a.1 Aquinas reasons that proper model of understanding how God can be seen per essentiam or face-to-face is that of Alexander (as explicated by Averroes) and Averroes whom he explicitly cites for this.  He writes regarding the mode by which this takes place that on their account

it is the separate substance itself which is conjoined to our intellect as form, so that it is what is understood and that by which it is understood.  And whatever is the case for other separate substances, nevertheless, we must accept that mode in the vision of God in his essence,  because, by whatever other form our intellect is informed, it cannot be brought through that to the divine essence.122

In the context of a discussion of whether angels see God in his essence in his De Veritate Aquinas repeats this interpretation of the position of Averroes and Alexander found in Book IV of the Commentary on the Sentences but only ascribes it to Averroes.  He writes,

How a separate essence can be joined to the intellect as form the Commentator shows as follows in Book 3[of his commentary on the De Anima: whenever two things one of which is more perfect than the other are received into something able to receive [them], the proportion of the more perfect to the less perfect is as the proportion of form to what it is able to perfect, as light is the perfection of color when both are received in a transparent [medium]. For this reason since the created intellect which is present in a created substance is more imperfect than the divine essence existing in it, the divine essence is compared in a certain way as form in relation to that which is understood.123

This is in the context of the supernatural epistemology of beatitude. A we find it here in In 2 Sent. d. 17, q. 2, a. 1,  Aquinas is dealing with natural epistemology. In later works Aquinas consistently rejects the teachings of Averroes on natural epistemology as well as those of Theophrastus, Themistius, Alexander, Avicenna, and Ibn Bâjjah, and crafts his own philosophical doctrine of intellectual understanding of the human soul.  For that doctrine Aquinas holds for agent and material / possible intellect to be intrinsic powers of each human soul.  And what are apprehended by the rational soul by means of these powers are not separate intelligibles in act in the separate Agent Intellect or in the separate Material Intellect but rather intelligible species which are themselves representations and rationes of the natures of things in the world.  What we have seen here is that in Book 2 of his Commentary on the Sentences Aquinas first establishes his own teachings on intellect and intelligibles in critical dialogue with philosophers of the Arabic / Islamic and Greek traditions in ways that would continue to inform the development of all his later thinking on human soul and intellect.124

1This study is a product of the Aquinas and the Arabs Project. For information, see www.AquinasAndTheArabs.org.

2 De Anima: Averrois Cordubensis Commentarium Magnum in Aristotelis De Anima Libros,  Crawford, F. S., ed. Cambridge, MA, 1953. Hereafter this work will be cited as LCDA with page numbers in brackets { }. An English translation of this is now available. See Averroes of Cordoba’s Long Commentary on the De anima of Aristotle, Richard C. Taylor, tr. and intro., Therese-Anne Druart, subeditor.  (New Haven: Yale University Press, 2009). This translation will be cited in what follows as LCDA, Taylor tr.

3 A provisional text of this article of Aquinas’s Commentary on the Sentences of Peter Lombard was prepared by the late P.-M. Gils, O.P.  My English translation is found in the Appendix below.  My thanks to Dr. Adriano Oliva, O.P., president of the Commissio Leonina, for providing the provisional Latin text used here. My thanks also to Prof. Isabelle Moulin for her helpful comments on a draft of my translation.

4 It is curious that Aquinas neglects to mention al-Fârâbî in this context since the latter’s Letter on the Intellect or De intellectu was available in Latin translation. Perhaps the reason for this was that this work was not easily at hand for Aquinas. Another reason may be that, while he made extensive use of the Long Commentary on the De Anima of Aristotle by Averroes as will be shown below, he did not fully understand the critical accounts of the teachings of al-Fârâbî as set forth by Averroes. The Latin text of al-Fârâbî’s De Intellectu was edited and discussed by Etienne Gilson in “Les sources greco-arabes de l'augustinisme avicennisant,” Archive d'histoire doctrinale et litteraire du moyen age 4 (1929),  4-149; see 115-126.  For a discussion of the importance of the teachings of al-Fârâbî to the development of the thought of Aquinas, see Richard C. Taylor, “Abstraction in al-Fârâbî,” Proceedings of the American Catholic Philosophical Association 80 (2006) 151-168. For a general account of the thought of al-Fârâbî, see Alfarabi, Avicenna, and Averroes, on Intellect. Their Cosmologies, Theories of the Active Intellect, and Theories of Human Intellect (Oxford: Oxford University Press, 1992), 44-73; and David C. Reisman, “Al-Fârâbî and the philosophical curriculum,” in The Cambridge Companion to Arabic Philosophy, Peter Adamson and Richard C. Taylor, eds. (Cambridge: Cambridge University Press, 2005), 52-71.

5 In 2 Sent. d. 17, q. 2, a. 1, sol.  See Appendix, Solution, section [C].

6 Among the key texts in Averroes are LCDA Book 3, Texts and Comments 5, 18-20, and 36. For Avicenna, the key text is Kitâb al-Shifâ’, al-Nafs, Part 5: Avicenna’s De Anima (Arabic Text) Being the Psychological Part of the Kitâb al-Shifâ’, F. Rahman, ed. (London: Oxford University Press, 1959), 202-269; Avicenna Latinus. Liber De Anima seu Sextus de Naturalibus I-II-III, S. Van Riet, ed. (Louvain: E. Peeters, and Leiden: E. J. Brill, 1972); Avicenna Latinus. Liber De Anima seu Sextus de Naturalibus IV-V, S. Van Riet, ed. (Louvain: Editions Orientalistes, and Leiden: E. J. Brill, 1968), vol. 2,  69-185.

7 These bracketed references are to my divisions of the text found in the translation in the Appendix.

8 This is al-caql bi-l-malakah. In my translations of the LCDA, I render intellectus in habitu as “intellect in a positive disposition.”

9 In 2 Sent. d. 17, q. 2, a. 1, sol.; section [B].

10 . . . referri ad hominem intelligentem. Et oportet addere in sermone: secundum quod facit ipsum intelligere omne ex se et quando voluerit. Hec enim est diffinitio habitus, scilicet ut habens habitum intelligat per ipsum illud quod est sibi proprium ex se et quando voluerit, absque eo quod indigeat in hoc aliquo extrinseco. LCDA {438}; Taylor tr., 350.

11 Avicenna, Latin, De Anima, 5.1, 81.78-82;  Arabic,  209.

12 The term “possible intellect” is taken from Aristotle, De Anima 429a21–24.

13 See Alexander of Aphrodisias, De Anima Liber Cum Mantissa, Ivo Bruns, ed. (Berlin: Typis et Impensis Georgii Reimer, 1887) [Commentaria in Aristotelem Graeca, Suppl. II, pt. 1] 81.24.

14 In 2 Sent. d. 17, q. 2, a. 1, sol.  Averroes provides a precise definition of the material intellect: Idest, diffinitio igitur intellectus materialis est illud quod est in potentia omnes intentiones formarum materialium universalium, et on est in actu aliquod entium antequam intelligat ipsum. LCDA, {387}.  “. . . the definition of the material intellect, therefore, is that which is in potency all the intentions of universal material forms and is not any of the beings in act before it understands any of them.” Taylor tr., 304.

15 Avicenna, Latin, De Anima, 5.1, 81.77; Arabic, 209.

16 Avicenna, Latin, De Anima, 5.1, 76.5-6.; Arabic, 206.

17 non habet naturam secundum hoc nisi naturam possibilitatis ad recipiendum formas intellectas materiales. LCDA  {387}; Taylor tr., 304.  Aquinas writes, Et dicitur intellectus possibilis qui est in potentia | ad recipiendum omnes formas intellectas, sicut uisus est | in potentia ad recipiendum omnes colores. In 2 Sent. d. 17, q. 2, a. 1, sol.

18 See note 14 for the text and translation.

19 Nos autem cum posuerimus intellectum materialem esse eternum et intellecta speculativa esse generabilia et corruptibilia eo modo quo diximus, et quod intellectus materialis intelligit utrunque, scilicet formas materiales et formas abstractas, manifestum est quod subiectum intellectorum speculativorum et intellectus agentis secundum hunc modum est idem et unum, scilicet materialis. LCDA {499}; Taylor tr., 398.

20 In 2 Sent. d. 17, q. 2, a. 1, sol.; section [B].

21 Avicenna, Latin, De Anima 5.5, 126.28-127.47; Arabic, 234-35.

22 facit intellectum qui est in potentia intelligere omnia in actu.  LCDA {437}; Taylor tr., 349.

23 facit omnem rem intellectam in potentia intellectam in actu postquam erat in potentia.  LCDA {438}; Taylor tr., 350.

24 . . . transferri in suo esse de ordine in ordinem. LCDA {439}Taylor tr., 351.  On the roots of this notion in al-Fârâbî, see my article cited in note 4.

25 This may include William of Auvergne and Roger Bacon among others. See Gilson’s “Pourquoi Saint Thomas a critiqué Saint Augustin,” cited in note 4, in particular, 67-72.

26 Note that Aquinas rejects this view in all his works with the exception of a brief and troubling remark in his late De unitate intellectus where he mentions that the principle of intellectual light is a separate substance, uel Deus secundum Catholicos, uel intelligentia ultima secundum Avicennam; “either God according to Catholics or the last intelligence according to Avicenna.” See Aquinas, De unitate intellectus, V, 368-70, Sancti Thomae de Aquino, Opera omnia 43 (Rome: Editori de San Tommaso, 1976), 314.  On this issue, see Alain de Libera, L’Unité de l’intellect. Commentaire du De unitate intellectus contra averroistas de Thomas d’Aquin (Paris: Librairie Philosophique J. Vrin, 2004), 497-8.

27 This is an accurate account of the view of Avicenna available in Latin texts. See the brief account of Avicenna’s view by Robert Wisnovsky in “Avicenna and the Avicennian Tradition,” The Cambridge Companion to Arabic Philosophy, eds. Peter Adamson  and Richard C. Taylor (Cambridge: Cambridge University Press, 2005) 92-136, specifically 96-105.  Also see Wisnovsky, Avicenna’s Metaphysics in Context (Ithaca, NY: Cornell University Press, 2003), Ch. 6 “Avicenna on Perfection and Soul. The Issue of Separability,” 113-141. Also see Davidson, Alfarabi, Avicenna, and Averroes on Intellect, 1992.

28 The De intellectu of Alexander was available in Latin translation from Arabic, but Aquinas makes no use of it here and instead relies completely on Averroes. R. A. Gauthier in his introduction to the Leonine edition of Aquinas’ Commentary on the De Anima finds that Aquinas never directly read this treatise by Alexander. See Sententia de anima, R. A. Gauthier, ed. (Rome: Commissio Leonina; Paris: Librairie philosophique J. Vrin, 1984) [Sancti Thomae de Aquino, Opera omnia XLV, 1], 230-31.  Averroes himself had in Arabic translation both Alexander’s the paraphrasing De Anima and his De intellectu. See LCDA, Taylor tr., introduction, lxxxi-lxxxii; and Herbert A. Davidson, Alfarabi, Avicenna, and Averroes on Intellect (Oxford: Oxford University Press, 1992), 259-60. The Latin translation of the De intellectu is edited by G. Théry, in “Autour du décret de 1210: II. Alexandre d’Aphrodise. Aperçu sur l’influence de sa noétique,” Bibliothèque thomiste 7 (Kain, Belgium, 1926) 3-120; see 74-82.

29 preparationem. The corresponding Greek is epitêdeiotês. See Alexander of Aphrodisias, De Anima Liber Cum Mantissa, 84.24–85.5.

30 Quidam enim dicunt intellectum | possibilem nichil aliud esse quam preparationem que est 135 in natura humana ad recipiendam impressionem intellectus | agentis, et hanc esse uirtutem corporalem consequentem | complexionem humanam.  In 2 Sent. d. 17, q. 2, a. 1, sol. In Averroes we find, Potest enim intelligi secundum Alexandrum quod intendebat per intellectum in potentia preparationem existentem in complexione humana, scilicet quod potentia et preparatio que est in homine ad recipiendum intellectum in respectu uniuscuiusque individui est prior tempore intellectu agenti. “For it can be understood according to Alexander that [Aristotle] meant by “intellect in potency” the disposition existing in the human compound, because the potency and disposition which is in a human being for receiving the intelligible with respect to any given individual is prior in time to the agent intellect.” LCDA {444}; Taylor tr., 355. In the text that immediately follows Averroes explains that this intelligible comes about when the immortal Agent Intellect is united to us as “form for us,” forma nobis, according to Alexander.

31 Cum igitur ex hoc corpore, quando fuerit mixtum aliqua mixtione, generabitur aliquid ex universo mixti ita quod sit aptum ut sit instrumentum istius intellectus qui est in hoc mixto, cum existit in omni corpore, et istud instrumentum est etiam corpus, tunc dicetur esse intellectus in potentia; et est virtus facta a mixtione que cecidit in corporibus, preparata ad recipiendum intellectum qui est in actu. LCDA 394}; Taylor tr., 310.  For the Greek, see Alexander of Aphrodisias, De Anima Liber Cum Mantissa, Ivo Bruns, ed., 112.11–16. On the unsatisfactory status of the editions of the Arabic of the De Intellectu, see Davidson, Alfarabi, Avicenna, and Averroes on Intellect 1992, 7, n. 2.

32 Sed hoc quod dixit Alexander nichil est. Hoc enim vere dicitur de omni preparatione, scilicet quod neque est corpus neque forma hec in corpore. Quare igitur appropriavit Aristoteles hoc preparationi que est in intellectu inter alias preparationes, si non intendebat demonstrare nobis substantiam preparati sed substantiam preparationis? Sed impossibile est dicere quod preparatio est substantia, cum hoc quod dicimus quod subiectum istius preparationis neque est corpus neque virtus in corpore. Et est illud quod conclusit demonstratio Aristotelis alia intentio ab ea secundum quam dicitur quod preparatio neque est corpus neque virtus in corpore. Et hoc manifestum est ex demonstratione Aristotelis. / Propositio enim dicens quod omne recipiens aliquid necesse est ut in eo non existat in actu aliquid ex natura recepti manifesta est ex eo quod substantia preparati et natura eius querit habere hoc predicatum secundum quod est preparatum. Preparatio enim non est recipiens, sed esse preparationis a recipiente est sicut accidentis proprii. Et ideo, cum fuerit receptio, non erit preparatio, et remanebit recipiens. Et hoc manifestum est et intellectum ab omnibus expositoribus ex demonstratione Aristotelis. LCDA {395-6}. “But there is nothing to what Alexander said. For this is truly said of every disposition, namely, that it is neither a body nor this [particular] form in a body. Why, then, of [all] the other [sorts of] dispositions did Aristotle select this for the disposition which is in the intellect, if he did not intend to show us the substance of the thing disposed but rather the substance of the disposition? But it is impossible to say that the disposition is a substance, while we say that the subject of that disposition is neither a body nor a power in a body. What Aristotle’s demonstration reaches is an intention different from this one according to which it is said that the disposition is neither a body nor a power in a body.  / This is evident from the demonstration of Aristotle. 396} For the proposition saying that everything which receives something must not have anything of the nature of the thing received existing in it in act is evident from the fact that the substance and nature of the thing disposed is able to have this aforementioned thing inasmuch as it is disposed . For the disposition is not the recipient but rather the being of the disposition on the part of the recipient is as [the being] of a proper accident. For this reason, when there is a reception, there will not be a disposition [any more] and the recipient will remain [in existence]. This is evident and thought by all the commentators from the demonstration of Aristotle.” LCDA, Taylor, tr., 312.

33 Et magis inopinabile de opinione Alexandri est hoc quod dixit quod prime preparationes ad intellecta et ad alias postremas perfectiones de anima sunt res facte a complexione, non virtutes facte a motore extrinseco ut est famosum ex opinione Aristotelis et omnium Peripateticorum. Ista enim opinio in virtutibus anime /  comprehensivis, si est secundum quod nos intelleximus, est falsa. A substantia enim elementorum et a natura eorum non potest fieri virtus distinguens comprehensiva; quoniam, si esset possibile ut a natura eorum et sine extrinseco motore fierent tales virtutes, tunc esset possibile ut postrema perfectio, que est intellecta, esset aliquod factum a substantia eorum elementorum ut color et sapor fiunt. Et ista opinio est similis opinioni negantium causas agentes et non concedentium nisi causas materiales; et sunt illi qui dicunt casum. Sed Alexander est maioris nobilitatis quam ut credat hoc; sed questiones que opponebantur ei in intellectu materiali coegerunt ipsum ad hoc. LCDA {397-8}; Taylor, tr., 314.

34 Dicere autem quod intellectus materialis est similis preparationi que est in tabula, non tabule secundum quod est preparata, ut exponit / Alexander hunc sermonem, falsum est. Preparatio enim est privatio aliqua, et nullam habet naturam propriam nisi propter naturam subiecti, et propter hoc fuit possibile ut preparationes diversentur in unoquoque ente. O Alexander, reputas Aristotelem intendere demonstrare nobis naturam preparationis tantum, non naturam preparati (et non est natura istius preparationis propria ei, si fuerit possibile sine cognitione nature preparati), sed naturam preparationis simpliciter, in quocunque sit? Ego autem verecundor ex hoc sermone et ex hac mirabili expositione. Si enim Aristoteles intendebat demonstrare naturam preparationis que est in intellectu per omnes sermones predictos in intellectu materiali, necesse est aut ut intendat demonstrare per eos naturam preparationis simpliciter, aut naturam preparationis proprie. Naturam autem preparationis proprie intellectui impossibile est demonstrari sine natura subiecti, cum preparatio propria unicuique subiecto currit cursu perfectionis et forme ex eo; sed oportet necessario per cognitionem nature preparationis scire naturam preparati. Et si intendebat per illos sermones demonstrare naturam preparationis simpliciter, tunc illud non est proprium intellectui, et omne hoc est perturbatio. Omnis enim preparatio, in eo quod est preparatio, vere dicitur nichil esse in actu ex eis que recipit, et quod est non passibile, et vere dicitur esse non corpus neque virtus in corpore. LCDA {430-431}.  “To say, however, that the material intellect is similar to the disposition which is in the tablet, not to the tablet insofar as it is what is disposed, as Alexander expounded 431} this account, is false. For the disposition is a certain privation and has no nature of its own except owing to the nature of the subject and for this reason it was possible for the dispositions to be different in each being. Oh, Alexander, you figured that Aristotle intends to demonstrate to us the nature of the disposition alone, not the nature of what is disposed (the nature of that disposition is not proper to it, if it has been possible [to know it] without knowing the nature disposed), but [with regard to] the nature of the disposition considered without qualification, in what sort of thing would it be? But I am ashamed of this account and of this fantastic exposition. For if Aristotle meant to demonstrate the nature of the disposition which is in the intellect through all the aforementioned accounts in regard to the material intellect, either he must mean to demonstrate through them the nature of the disposition considered without qualification or the nature of the proper disposition. It is impossible, however, that the nature of the disposition proper to the intellect be demonstrated without the nature of the subject, since the disposition proper to each subject is consequent upon the actuality and form it has from it. But knowing the nature of the disposed subject must necessarily be through knowledge of the nature of the disposition. And if he meant by these accounts to demonstrate the nature of the disposition considered without qualification, then that is not something proper to the intellect and all this is confusion. For every disposition, insofar as it is a disposition, is truly said to be nothing in act [apart] from these things which it receives and [to be] something which is impassible, and it is truly said to be neither a body nor a power in a body.” Taylor tr., 344.

35 . . . impossibilia contingentia Alexandro, scilicet quod subiectum recipiens formas intellectas est corpus factum ab elementis, aut virtus in corpore . . . . LCDA {397}; Taylor tr., 313.

36 Lines 146-47; 440-41; and 141-44, respectively.

37 As we shall see, Averroes asserts that the separate agent intellect and the separate material intellect must be “in” the soul as intrinsic to every intellectually understanding human soul but not in the body. In the response to the first objection in the present article, Aquinas writes that the intellect is a material form “since it gives being to matter as substantial form with reference to first being,” though it has second being or act which an immaterial operation. Later in the Summa theologiae (Ottawa, 1953), Ia, q.76, a. 1, resp., Aquinas asserts that the intellect is the form of the human body, but he qualifies this statement in his response to the fourth objection where he writes that “the human soul is not a form immersed in corporeal matter or totally comprehended by [matter], owing to its perfection. For this reason nothing prevents one of its powers from not being the act of a body, although the soul according to its essence is the form of a body.” Ad quartum dicendum quod humana anima non est forma in materia corporali immersa, vel ab ea totaliter comprehensa, propter suam perfectionem. Et ideo nihil prohibet aliquam eius virtutem non esse corporis actum; quamvis anima secundum suam essentiam sit corporis forma.

38 In 2 Sent. d. 17, q. 2, a. 1, sol.

39 The Latin translation has Abucher (Abû Bakr) here which Aquinas readily understood to be a transliteration of part of the name of Ibn Bâjjah.

40 Abubacher autem videtur intendere in manifesto sui sermonis quod intellectus materialis est virtus ymaginativa secundum quod est preparata ad hoc quod intentiones que sunt in ea sint intellecte in actu, et quod non est alia virtus subiecta intellectis preter istam virtutem. LCDA {397}; Taylor tr., 313.

41 . . . et ideo oportet quod fantasmata | sint mouentia intellectum possibilem sicut color mouet | uisum; et aptitudo que est in intellectu possibili ad | intelligendum est similis aptitudini que est in patiente | in potentia ut sit patiens actu, aptitudo autem que est 160 in ymaginatiua est sicut aptitudo agentis in potentia ut | sit agens in actu. Impossibile est autem idem esse mouens | et motum et agens et patiens. Ergo impossibile est quod | uirtus ymaginatiua sit intellectus possibilis. Lines 155-62. “For this reason it is necessary that the phantasms be what move the possible intellect, as color moves vision. The ability which is in the possible intellect for understanding is similar to the ability which is in the patient in potency so that it may be patient in act. The ability which is in the imaginative [power] is as the ability of the agent in potency so that it may be agent in act.  However, it is impossible that the same thing be mover and moved, agent and patient.  Therefore, it is impossible that the imaginative power be the possible intellect.”

42 Sed quod accidit ei impossibile manifestum est. Intentiones enim ymaginate sunt moventes intellectum, non mote. Declaratur enim quod sunt illud cuius proportio ad virtutem distinctivam rationabilem est sicut proportio sensati ad sentiens, non sicut sentientis ad habitum qui est sensus. Et si esset recipiens intellecta, tunc res reciperet se, et movens esset motum. LCDA {398}; Taylor tr., 314.  Averroes also remarks that Ibn Bâjjah was deceived regarding the active disposition of the imagination and the receptive disposition of the material intellect.  Et propter hanc similitudinem inter has duas preparationes existimavit Avempeche quod nulla est preparatio ad rem intellectam fiendam nisi preparatio existens in intentionibus ymaginatis. Et hee due preparationes differunt sicut terra a celo; una enim est preparatio in motore ut sit motor, alia autem est preparatio in moto ut sit motum et recipiens. LCDA 406}. “Owing to this similarity between these two dispositions, Ibn Bâjjah thought that there is no disposition for the thing coming to be understood except the disposition existing in the imagined intentions. But these two dispositions differ as [much as] the earth from the heavens. For one is the disposition in the mover insofar as it is a mover and the other is a disposition in the moved insofar as it is moved and receptive.” Taylor tr., 321.

43 Preparatio autem que est in virtute ymaginativa intellectorum similis est preparationibus que sunt in aliis virtutibus anime, scilicet perfectionibus primis aliarum virtutum anime, secundum hoc quod utraque preparatio generatur per generationem individui, et corrumpitur per corruptionem eius, et universaliter numeratur per numerationem eius. Et differunt in hoc quod illa est preparatio in motore ut sit motor, scilicet preparatio que est in intentionibus /

ymaginatis; secunda autem est preparatio in recipiente, et est preparatio que est in primis perfectionibus aliarum partium anime.  LCDA 405-6}. “However, the disposition for intelligibles which is in the imaginative power is similar to the dispositions which are in the other powers of the soul, namely, [similar] to the first actualities of the other powers, inasmuch as each of these two [sorts of] dispositions is generated through the generation of an individual, corrupted through its corruption, and generally numbered through its numbering. They differ in this: one is a disposition in a mover insofar as it is a mover, namely, the disposition which is in the intentions / imagined; the other is a disposition in the recipient and is a disposition which is in the first actualities of the other parts of the soul.” Taylor tr., 320-21.

44 See above, n. 14.  Ibn Bajja’s views are more complex than can adequately be conveyed here. Suffice it to say, he tried to avoid the problems of the materialism of Alexander by making the subject of received intelligibles the power of imagination which, while not a body, is nevertheless a power in a body.  For a short account of the thought of Ibn Bâjjah, see Josep Puig Montada, Josep, “Ibn Bajja,” in The Stanford Encyclopedia of Philosophy, Edward N. Zalta,  ed., URL = http://plato.stanford.edu/entries/ibn-bajja/. First published September 28, 2007.

45 In 2 Sent. d. 17, q. 2, a. 1, sol.

46 On this see my article,  “Intelligibles in act in Averroes,” in Averroès et les averroïsmes juif et latin. Actes du colloque tenu à Paris, 16-18 juin 2005, J.-B. Brenet, ed. (Turnhout: Brepols, 2007) 111-140.

47 In 2 Sent. d. 17, q. 2, a. 1, sol.

48 Averroes is the source of this critique. Et si posuerimus eum esse multa, continget ut res intellecta apud me et apud te sit una in specie et due in individuo; et sic res intellecta habebit rem intellectam, et sic procedit in infinitum. “If we assert it [scil., the intelligible] to be many, then it would happen that the thing understood in me and in you would be one in species and two in individual [number]. In this way the thing understood will have a thing understood and so it proceeds into infinity.” Averroes, LCDA {411}, Taylor tr. 328. . . . prima materia recipit formas diversas, scilicet individuales et istas, ista autem recipit formas universales  “. . . prime matter receives diverse forms, namely, individual and particular forms, while this [nature] receives universal forms.” Averroes, LCDA {388}, Taylor tr. 304.  See the continuation of Averroes’s account at LDCA {388}, Taylor tr. 304-5.

49 In 2 Sent. d. 17, q. 2, a. 1, sol.

50 Et causa propter quam ista natura est distinguens et cognoscens, prima autem materia neque cognoscens neque distinguens, est quia prima materia recipit formas diversas, scilicet individuales et istas, ista autem recipit formas universales. Et ex hoc apparet quod ista natura non est aliquid hoc, neque corpus neque virtus in corpore; quoniam, si ita esset, tunc reciperet

formas secundum quod sunt diversa et ista, et si ita esset, tunc forme existentes in ipsa essent intellecte in potentia, et sic non distingueret naturam formarum secundum quod sunt forme, sicut est dispositio in formis individualibus, sive spiritualibus sive corporalibus. Et ideo necesse est, si ista natura que dicitur intellectus recipit formas, ut recipiat formas modo alio receptionis ab eo

secundum quem iste materie recipiunt formas quarum conclusio materia est terminatio prime materie in eis. LCDA, 388; Taylor tr., 304-5.

51 The key role of Themistius in the development of Averroes’s thought in the Long Commentary is discussed in LCDA, Taylor, tr., introduction, lxii ff.; and in my “Themistius and the Development of Averroes’ Noetics,” in Soul and Mind. Medieval Perspectives on Aristotle's De Anima (Philosophes Médiévaux LII),  J.-M. Counet and R. Friedman, ed. (Peeters Publisher, Leuven, forthcoming).

52 Et iste modus secundum quem posuimus essentiam intellectus materialis dissolvit omnes questiones contingentes huic quod ponimus quod intellectus est unus et multa. Quoniam, si res intellecta apud me et apud te fuerit una omnibus modis, continget quod, cum ego scirem aliquod intellectum, ut tu scires etiam ipsum, et alia multa impossibilia. Et si posuerimus eum esse multa, continget ut res intellecta apud me et apud te sit una in specie et due in individuo; et sic res intellecta habebit rem intellectam, et sic procedit in infinitum. Et sic erit impossibile ut discipulus addiscat a magistro, nisi scientia que est in magistro sit virtus generans et creans scientiam que est in discipulo, ad modum secundum quem iste ignis generat alium / ignem sibi similem in specie; quod est impossibile. Et hoc quod scitum est idem in magistro et discipulo ex hoc modo fecit Platonem credere quod disciplina esset rememoratio. Cum igitur posuerimus rem intelligibilem que est apud me et apud te multam in subiecto secundum quod est vera, scilicet formas ymaginationis, et unam in subiecto per quod est intellectus ens (et est materialis), dissolvuntur iste questiones perfecte. LCDA, 411-12. Taylor tr., 328-29.

53 In his Metaphysics of the Shifâ’ Avicenna makes his famous distinction of the three ways quiddity can exist: in things, in the soul or absolutely. Ibn Sînâ, al-Shifâ’. Al-Ilâhiyyât, vol. 1, G. C. Anawati and Sa’id Zayed, ed. (Cairo: Organisation Générale des Imprimeries Gouvernementales, 1960), 31; Avicenna Latinus. Liber de Philosophia Prima sive Scientia Divine, I-V, S. Van Riet, ed. (Louvain: Peeters; Leiden: E. J. Brill, 1977), 35; Avicenna, The Metaphysics of The Healing, Michael E. Marmura, tr. (Provo, Utah: Brigham Young University Press, 2005), 24.  In his De Anima he says that the formation of universal intelligible intentions altogether separate from matter is the most proper characteristic of human beings, at Latin 76, Arabic  206. (See note 58 for the texts.) He later argues that the receptive subject of intelligible forms must be an immaterial substance. Latin 89, Arabic 214.  At Latin 127-28, Arabic 235, he explains that the human rational power considers individuals in the imagination and next the light of the Agent Intellect strips these intelligibles in potency of materiality and emanates the immaterial intelligible in act upon the rational soul. “What are in the imagination are intelligibles in potency and they become intelligibles in act.” For Avicenna, then, the being that an intelligible in act has in the human intellect of an individual is distinct from the being of the intelligible in potency in the imagination since the latter is the being of a particular or singular because of its relation to the particular or singular in the world which is the cause of the image in the imagination and because of its presence in a power of a body, the imagination broadly considered.

54 All the translations in this paragraph are drawn from Sent. d. 17, q. 2, a. 1, ad 3.

55 Haec autem forma, quamvis respectu individuorum sit universalis, tamen, respectu animae singularis in qua imprimitur, est individua ; ipsa enim est una ex formis quae sunt in intellectu, et quia singulae animae sunt multae numero, tunc eo modo quo sunt particulares habebunt ipsae aliud intellectum universale. Avicenna, Metaphysics 5.1, Latin v. 2, 238; Arabic, v. 2, 205-6. Marmura, 157, translates the Arabic as follows. “This form, although a universal in relation to individuals, is an individual in relation to the particular soul in which it is imprinted, being one of the forms of the mind. And, because individual souls are numerically many, it is possible for this universal form to be numerically many from the aspect that it is individual.” As Van Riet notes, the Latin suffers from an omission here. Still, Aquinas is able to take from this passage the view of Avicenna that the universal is received in a plurality of individual human souls or intellects without losing its nature as an intelligible.

56 See Avicenna, Metaphysics 5.2, Latin v. 2, 241, Arabic, v.2, 209; Marmura tr., 159.

57 Cum ergo dicimus quod natura universalis habet esse in his sensibilibus, non intelligimus quod ex hoc quod est universalis, scilicet secundum hunc modum universalitatis, sed intelligimus quod natura cui accidit universalitas habet esse in istis signatis. Avicenna, Metaphysics 5.2, Latin v. 2, 244, Arabic, v.2, 211;   “If we then say that the universal nature exists in external things, we do not mean in as much as it is universal in this mode of universality; rather, we mean that the nature to which universality occurs exists in things external [to the mind].” Marmura tr., 161.

58 Quae autem est magis proprie ex proprietatibus hominis, haec est scilicet formare intentiones universales intelligibiles omnino abstractas a materia. De Anima, Latin 5.1, v.2, 76.5-6; Arabic, 206: wa-akhaṣṣu akhaṣâṣi bi-l-insâni taṣawwuru al-macânà al-kullîyati al-mujarradati can al-mâdati.

59 In his Letter on the Intellect, al-Fârâbî writes regarding intelligibles in act, “[T]he meanings of these categories or many of them must be understood in some other senses, different from those senses, for example, place when it is considered in regard to the intelligible in actuality. For if you consider the meaning of place in regard to it, either you will not find in it any of the meanings of place at all, or, if you should apply the term ‘place’ it must be understood by you in regard to it in a different meaning, and this meaning according to a different sense.” Alfarabi. Risalah fî al-caql, Maurice Bouyges, S.J., ed. (Beyrouth: Dar el-Machreq Sarl, 1983, 2nd ed.), 17.7-8; Arthur Hyman, tr.,  in Philosophy in the Middle Ages, ed. Arthur Hyman and James J. Walsh (Indianapolis: Hackett Publishing Co., 1973, 2nd ed.), 216. For a discussion of intelligibles and abstract in al-Fârâbî, see my article, “Abstraction in al-Fârâbî,” Proceedings of the American Catholic Philosophical Association 80 (2006) 151-168.

60 Iam autem diximus quod corpus earum et quod pendet ex corpore earum non est dignum ad hoc, nec est dignum ut sit subiectum intelligibilium, quia non est dignum ut formae intellectae sint habentes situm, sed coniunctio earum cum corpore faciet eas habere situm ; si autem essent in corpore habentes situm, non essent intelligibiles. “However, we already said that the body of these and what depends on body from among these is not fitting for this, nor is it fitting that it be the subect of intelligibles, because it is not fitting that understood forms be things having place, but rather the conjunction of these with the body will make these have place. If, however, they were in body [and were to] have place, they would not be intelligibles.” Avicenna, De Anima 5.6, Latin v. 2, p.146; Arabic, 245.

61 At De Anima 1.5, Latin v.1, 98-99, Arabic 50, Avicenna states that this comes about through a conjoining (aliquo modo coniunctionis, nawcan min ittiṣâl) with an external intellect which is in act, that is, the Agent Intellect.

62 Avicenna, Latin, De Anima, 5.5, Latin v. 2, 126-27; Arabic, 234-35.  At Latin, De Anima, 5.6, v.2, 147, Arabic 245, the metaphor of emanation is again used to describe this.  For a short account of the importance of internal senses in the Arabic / Islamic tradition, including Avicenna, see Alfred L. Ivry, “Arabic and Islamic Psychology and Philosophy of Mind,” in The Stanford Encyclopedia of Philosophy, Edward N. Zalta, ed., URL = http://plato.stanford.edu/entries/arabic-islamic-mind/. First published April 18, 2008.

63 Avicenna, Latin, De Anima, 5.6, v.2, 149-50; Arabic, 247-48.

64 In his later Disputed Questions on Soul Aquinas describes this as follows: [L]icet species intelligibilis qua intellectus formaliter intelligit sit in intellectu possibili istius uel illius hominis, ex quo intellectus possibiles sunt plures, id tamen quod intelligitur per huiusmodi species est unum, si consideremus habito respectu ad rem intellectam, quia uniuersale quod intelligitur ab utroque est idem in omnibus. Et quod per species multiplicatas in diuersis id quod est unum in omnibus possit intelligi, contingit ex immaterialitate specierum, que representant rem absque materialibus conditionibus indiuiduantibus, ex quibus una natura secundum speciem multiplicatur numero in diuersis. Thomas Aquinas, Quaestiones disputatae De anima, Q.5, A.3, ad 7. “Although the intelligible species by which the intellect formally understands is in the possible intellect of this or that human being, from which [it follows that] there are many possible intellects, nevertheless that which is understood through species of this sort is one, if we consider it with respect to the thing understood. [This is] because the universal which is understood by both is the same in all.  And because that which is one in all can be understood through species multiplied in diverse [human intellects], this occurs from the immateriality of the species which represent the thing without individuating material conditions from which a nature one in species is multiplied in number in diverse [human intellects].”

65 In 2 Sent. d. 17, q. 2, a. 1, ad 3.

66 In 2 Sent. d. 17, q. 2, a. 1, ad 3.

67 Averroes develops his view of the separate material intellect in critical engagement with Themistius, as I have shown in my introduction to LCDA Taylor tr.  For a more detailed account, see my article, “Themistius and the Development of Averroes’ Noetics,” cited in n. 51.

68 In 2 Sent. d. 17, q. 2, a. 1, sol.

69 In 2 Sent. d. 17, q. 2, a. 1, sol.

70 In 2 Sent. d. 17, q. 2, a. 1, sol. Averroes writes, Et ex hoc apparet quod ista natura non est aliquid hoc, neque corpus neque virtus in corpore; quoniam, si ita esset, tunc reciperet

formas secundum quod sunt diversa et ista, et si ita esset, tunc forme existentes in ipsa essent intellecte in potentia, et sic non distingueret naturam formarum secundum quod sunt forme, sicut est dispositio in formis individualibus, sive spiritualibus sive corporalibus. “From this it is apparent that this nature [scil. the material intellect] is not a determinate particular nor a body nor a power in a body. For if it were so, then it would receive forms inasmuch as they are diverse and particular, and if it were so, then the forms existing in it would be intelligibles in potency; and thus it would not discern the nature of the forms inasmuch as they are forms, as is the disposition in the case of individual forms, be they spiritual or corporeal.” LCDA {388}; Taylor tr., 304-5.

71 LCDA {389}.

72 In 2 Sent. d. 17, q. 2, a. 1, sol.

73Themistius, In Libros Aristotelis De Anima Paraphrasis, ed. R. Heinze, Berlin, G. Reimeri, 1899, [Commentaria in Aristotelem Graeca, 5.3], p. 103.36-104.3; Themistius, On Aristotle’s On the Soul, tr. Robert B.Todd, Ithaca, N.Y., Cornell University Press, 1996, p.129. The corresponding Arabic text has, “There need be no wonder that we all are as a group composites of what is in potency and of what is in act.  All of us whose existence is by virtue of this one are referred back to a one which is the Agent Intellect. For if not this, then whence is it that we possess known sciences in a shared way? And whence is it that the understanding of the primary definitions and primary propositions is alike [for us all] without learning?  For it is right that, if we do not have one intellect in which we all share, then we also do not have understanding of one another.” An Arabic Translation of Themistius’ Commentary on Aristotle's De Anima, M. C. Lyons, ed., (Columbia, South Carolina, and Oxford, England, 1973), 188-189; my translation.

74 For a discussion, see the article cited in note 51.

75 In 2 Sent. d. 17, q. 2, a. 1, sol. Cf. Averroes.  Si enim formare per intellectum esset eternum, oporteret ut formatum per intellectum esset eternum, quapropter necesse esset ut forme sensibiles essent intellecte in actu extra animam, et non materiales omnino . . . .  LCDA {391}. “For if conceptualization were eternal, then it would be necessary for what is conceptualized to be eternal. Hence, it would be necessary for the sensible forms to be intelligibles in act outside the soul and not [be] material at all.” Taylor tr., 307. Also see LCDA {452}.

76 In 2 Sent. d. 17, q. 2, a. 1, sol. Cf. Averroes, [S]i intellectus materialis est prima perfectio hominis, ut declaratur de diffinitione anime, et intellectus speculativus est postrema perfectio, homo autem est generabilis et corruptibilis et unus in numero per suam postremam

perfectionem ab intellectu, necesse est ut ita sit per suam primam perfectionem, scilicet quod per primam perfectionem de intellectis sim alius a te, et tu alius a me (et si non, tu esses per esse mei, et ego per esse tui . . . . LCDA {392}. “[I]f the material intellect is the first actuality of a human being, as it is explained concerning the definition of the soul, and the theoretical intellect is the final actuality, but a human being is generable and corruptible and [yet also] one in number in virtue of his final actuality by the intellect, then it is necessary that he be so in virtue of his own first actuality. That is, [it must be the case] that I be other than you in virtue of the first actuality in reference to intelligibles and you be other than I. If not, you would exist in virtue of the being belonging to me and I would exist in virtue of the being belonging to you.” Taylor tr., 308-9.

77 In 2 Sent. d. 17, q. 2, a. 1, sol.  Cf. Averroes.  Et ideo opinatus est Themistius quod nos sumus intellectus agens, et quod intellectus speculativus nichil est aliud nisi continuatio intellectus agentis cum intellectu materiali tantum.  Et non est sicut existimavit, sed opinandum est quod in anima sunt tres partes intellectus, quarum una est intellectus recipiens, secunda autem est efficiens, tertia autem factum. Et due istarum trium sunt eterne, scilicet agens et recipiens; tertia autem est generabilis et corruptibilis uno modo, eterna alio modo.  LCDA 406}. “For this reason Themistius held the opinion that we are the agent intellect and that the theoretical intellect is nothing else but just the conjoining of the agent intellect with the material intellect. It is not as he thought. Rather, one should hold the opinion that there are three parts of the intellect in the soul, one is the receptive intellect, the second is that which makes [things], and the third is the product [of these]. Two of these three are eternal, namely, the agent and the recipient; the third is generable and corruptible in one way, eternal in another way.” Taylor tr., 321.

78 In 2 Sent. d. 17, q. 2, a. 1, sol.  Cf. Averroes. Modo dat modum ex quo oportuit ponere in anima intelligentiam agentem. Non enim possumus dicere quod proportio intellectus agentis in anima ad intellectum generatum est sicut proportio artificii ad artificiatum omnibus modis. Ars enim imponit formam in tota materia absque eo quod in materia sit aliquid existens de intentione forme antequam artificium fecerit eam. Et non est ita in intellectu; quoniam, si ita esset in intellectu, tunc homo non indigeret, in comprehendendo intelligibilia, sensu neque ymaginatione; immo intellecta pervenirent in intellectum materialem ab intellectu agenti, absque eo quod intellectus materialis indigeret aspicere formas sensibiles. Neque etiam possumus dicere quod intentiones ymaginate sunt sole moventes intellectum materialem et extrahentes eum de potentia in actum; quoniam, si ita esset, tunc nulla differentia esset inter universale et individuum, et tunc intellectus esset de genere virtutis ymaginative. Unde necesse est, cum hoc quod posuimus quod proportio intentionum / ymaginatarum ad intellectum materialem est sicut proportio sensibilium ad sensus (ut Aristoteles post dicet), imponere alium motorem esse, qui facit eas movere in actu intellectum materialem (et hoc nichil est aliud quam facere eas intellectas in actu, abstrahendo eas a materia). LCDA 438-39}. “Now he gives the way on the basis of which it was necessary to assert the agent intelligence to be in the soul. For we cannot say that the relation of the agent intellect in the soul to the generated intelligible is just as the relation of the artistry to the art’s product in every way. For art imposes the form on the whole matter without it being the case that there was something of the intention of the form existing in the matter before the artistry has made it. It is not so in the case of the intellect, for if it were so in the case of the intellect, then a human being would not need sense or imagination for apprehending intelligibles. Rather, the intelligibles would enter into the material intellect from the agent intellect, without the material intellect needing to behold sensible forms. And neither can we even say that the imagined intentions are solely what move the material intellect and draw it out from potency into act. For if it were so, then there would be no difference between the universal and the individual, and then the intellect would be of the genus of the imaginative power. Hence, in view of our having asserted that the relation of the imagined intentions 439} to the material intellect is just as the relation of the sensibles to the senses (as Aristotle will say later), it is necessary to suppose that there is another mover which makes [the intentions] move the material intellect in act, and this is nothing but to make [the intentions] intelligible in act by separating them from matter.” Taylor tr., 350.

79 See LCDA {225-26}; {384-85}; {476-77}.  Cf. Richard C. Taylor, “Remarks on Cogitatio in Averroes’ Commentarium Magnum in Aristotelis De Anima Libros,” in Averroes and the Aristotelian Tradition: Sources, Constitution and Reception of the Philosophy of Ibn Rushd (1126-1198), Jan A. Aertsen and Gerhard Endress, ed., (Leiden: Brill, 1999), 217-255;  “Cogitatio, Cogitativus and Cogitare: Remarks on the Cogitative Power in Averroes,” in L’elaboration du vocabulaire philosophique au Moyen Age, J. Hamesse et C. Steel, ed., (Turnhout: Brepols, 2000), 111-146; and LDCA Taylor, tr., introduction, liii-lxvi; lxix-lxxvi.

80 Ars enim imponit formam in tota materia absque eo quod in materia sit aliquid existens de intentione forme antequam artificium fecerit eam. Et non est ita in intellectu; quoniam, si ita esset in intellectu, tunc homo non indigeret, in comprehendendo intelligibilia, sensu neque ymaginatione. LCDA 438}; Taylor, tr., 350.

81 The doctrine of abstraction of intelligibles from imagined intentions is found in al-Fârâbî, embraced by Averroes, and passed on to Aquinas, as I explain in “Abstraction in al-Fârâbî,” Proceedings of the American Catholic Philosophical Association 80 (2006) 151-168.

82 Abstrahere enim nichil est aliud quam facere intentiones ymaginatas intellectas in actu postquam erant in potentia; intelligere autem nichil aliud est quam recipere has intentiones. LCDA {439}; Taylor, tr., 351.

83 In contrast, for Avicenna the traditional understanding is that the abstractive powers of the soul function to prepare the rational soul for the reception of an emanation of intelligible forms or for a conjoining with the forms in the separate agent intellect.  That commonly held view has been challenged recently by Dimitri Gutas and Dag Hasse with a more abstractionist account in Dimitri Gutas, “Intuition and Thinking: The Evolving Structure of Avicenna's Epistemology,” in Robert Wisnovsky (ed.), Aspects of Avicenna. Princeton, Markus Wiener Publishers, 2001 (reprinted from Princeton Papers: Interdisciplinary Journal of Middle Eastern Studies, Vol. IX) p.1-38; and Dag Nikolaus Hasse, “Avicenna on Abstraction,” ibid., p. 39-72.  More recently Jon McGinnis has proffered an altogether novel understanding of the issues which deserves careful consideration. See his “Making Abstraction Less Abstract: The Logical, Psychological, and Metaphysical Dimensions of Avicenna’s Theory of Abstraction,” Proceedings of the American Catholic Philosophical Association 80 (2007) 169-183. McGinnis explicates his novel account in his paper in the present volume. My own view, however, is Avicenna’s explanation may well be in accord with late Neoplatonic accounts which involve both abstraction in relation to perceptual experience and a conjoining with a transcendent intellect containing the intelligible forms. See Cristina D’Ancona, “Degrees of Abstraction in Avicenna. How to Combine Aristotle’s De Anima and the Enneads,” in Theories of Perception in Medieval and Early Modern Philosophy, Simo Knuuttila and Pekka Kärkkäinen, ed., (Dordrecht: Springer, 2008), 45-71; and Cristina D’Ancona, “Man’s Conjunction with Intellect: A Neoplatonic Source of Western Muslim Philosophy,” Proceedings of the Israel Academy of Sciences and Humanities VIII 4 (2008), 57-89. Avicenna knew the Paraphrase of the De Anima by Themistius so it may well be that Themistius plays an important role in the very different doctrines developed by Avicenna and Averroes. See Dimitri Gutas, Avicenna and the Aristotelian Tradition (Leiden: Brill, 1988), 313; also see 289 and 291.

84 For a detailed discussion of how these intellects must be intrinsic to the soul, see my article, “Intellect as Intrinsic Formal Cause in the Soul according to Aquinas and Averroes,” The Afterlife of the Platonic Soul: Reflection on Platonic Psychology in the Monotheistic Religions, John Dillon and Maha El-Kaisy Friemuth, ed. (Leiden: Brill, 2009), 187-220.

85 On this see Taylor,  “Intelligibles in act in Averroes,” cited in note 46.

86 In 2 Sent. d. 17, q. 2, a. 1, sol.  The complete text of Averroes from which Aquinas extracts his account is as follows. Cf. Et hoc subiectum intellectus quod est motor illius quoquo modo est illud quod reputavit Avempeche esse recipiens, quia invenit ipsum quandoque intellectum in potentia et quandoque intellectum in actu, et ista est dispositio subiecti recipientis, et existimavit conversionem. Page 401 Et ista proportionalitas magis invenitur perfecta inter subiectum visus quod movet ipsum et inter subiectum intellectus quod movet ipsum. Quemadmodum enim subiectum visus movens ipsum, quod est color, non movet ipsum nisi quando per presentiam lucis efficitur color in actu postquam erat in potentia, ita intentiones ymaginate non movent intellectum materialem nisi quando efficiuntur intellecte in actu postquam erant in potentia. Et propter hoc fuit necesse Aristoteli imponere intellectum agentem, ut videbitur post; et est extrahens has intentiones de potentia in actum. Quemadmodum igitur color qui est in potentia non est prima perfectio coloris qui est intentio comprehensa, sed subiectum quod perficitur per istum colorem est visus, ita etiam subiectum quod perficitur per rem intellectam non est intentiones ymaginate que sunt intellecte in potentia, sed intellectus materialis est qui perficitur per intellecta; et est + cuius proportio ad ea + est sicut proportio intentionis coloris ad virtutem visibilem. Et cum omnia ista sint sicut narravimus, non contingit ut ista intellecta que sunt in actu, scilicet speculativa, ut sint generabilia et corruptibilia nisi propter subiectum per quod sunt vera, non propter subiectum per quod sunt unum entium, scilicet intellectum materialem. LCDA 400-01}. “This intellect’s subject, which is its mover in some way, is what Ibn Bâjjah held to be the recipient, because he found it sometimes to be intellect in potency and sometimes to be intellect in act—that is, the disposition of a recipient subject—and he thought the converse [as well]. {401} That proportionality is found to be more exact between the subject of vision which moves [vision] and the subject of the intellect which moves [intellect]. For just as the subject of vision moving [vision], which is color, moves it only when color is made to exist in act through the presence of light after it was in potency, so too the imagined intentions move the material intellect only when the intelligibles are made to exist in act after they were in potency. For this reason Aristotle had to posit the agent intellect, as will be seen later. It is this which draws out these intentions from potency into act. Therefore, just as color which is in potency is not the first actuality of the color which is the apprehended intention but rather the subject actualized through that color is vision, so too the subject actualized through the thing understood is not the imagined intentions which are intelligibles in potency, but rather the material intellect, which is actualized through the intelligibles. And so it is + that the relation of [the material intellect] to [the intelligibles] + is as the relation of the intention of color to the power of vision.

Since all those things are as we recounted, it happens that those intelligibles which are in act, namely, the theoretical [intelligibles], are generable and corruptible only in virtue of the subject in virtue of which they are true, not in virtue of the subject in virtue of which they are one of the beings, namely, the material intellect.” Taylor tr., 316-17.

87  In 2 Sent. d. 17, q. 2, a. 1, sol.

88  In 2 Sent. d. 17, q. 2, a. 1, sol.

89 For an extended discussion, see my article, “Personal Immortality in Averroes’ Mature Philosophical Psychology,” Documenti e Studi sulla Traduzione Filosofica Medievale 9 (1998) 87-110.

90 In 2 Sent. d. 17, q. 2, a. 1, sol.

91 In 2 Sent. d. 17, q. 2, a. 1, sol.

92 In 2 Sent. d. 17, q. 2, a. 1, sol.

93 It should be noted that Averroes was well aware that his interpretation of Aristotle was novel in the tradition, though he thought it the most reasonable understanding of Aristotle. He calls the Material Intellect a “fourth kind of being” since it is not matter, not form and not the composite of these but rather something altogether distinct and unique: an intellect which is essentially receptivity for intelligibles in act while also being a separate and immaterial substance. Opinandum est enim quod iste est quartum genus esse. Averroes, LCDA {409}.

94 In 2 Sent. d. 17, q. 2, a. 1, sol.

95 The view of Averroes is discussed in LCDA Taylor tr., introduction, lxii-lxxv. Also see “Themistius and the Development of Averroes’ Noetics,” cited in note 51; and “Intellect as Intrinsic Formal Cause in the Soul according to Aquinas and Averroes,” cited in n. 84.

96 This phraseology is used by Averroes at  LCDA {390}; {406}; {437}; and {438}.

97 Averroes understood another alternative to be the view of al-Fârâbî that the Agent Intellect is only a cause acting on the human soul, not as “form for us.”  Regarding al-Fârâbî, see see my article cited in note 4. Also see: Ph. Vallat, Farabi et l’École d’Alexandrie. Des prémisses de la connaissance à la philosophie politique, (Paris, 2004); M. Geoffroy, “La tradition arabe du Peri; nou` d'Alexandre d'Aphrodise et les origines de la théorie farabienne des quatre degrés de l'intellect” in Aristotele e Alessandro di Afrodisia nella Tradizione Araba, C. D'Ancona and G. Serra, eds., (Subsidia Mediaevalia Patavina 3), (Padova, 2002), 191-231.  Also see my article,  “The Agent Intellect as ‘form for us’ and Averroes’ Critique of al-Fârâbî” in Topicos (Universidad Panamericana, Mexico City) (29) 2005, p. 29-51. Reprint with corrections in Proceedings of the Society for Medieval Logic and Metaphysics (5) 2005, p. 18-32  http://www.fordham.edu/gsas/phil/klima/SMLM/PSMLM5/PSMLM5.pdf.

98 ṣûrah la-nâ / forma in nobis. “[I]t is clear that its intellect can belong to us ultimately. I mean insofar as it is form for us and it is such that it has generated for us as necessary an eternal intelligible. Since it is itself an intellect whether or not we have intellectual understanding of it, it is not the case that its existence as intellect is from our activity as is the case in regard to material intelligibles.” Talkhīṣ Kitāb al-Nafs, A. F. El-Ahwani, ed. (Cairo, 1950), 89.3-6; Epitome de Anima, S. Gómez Nogales, ed. (Madrid, 1985), 127.7-10; La Psicología de Averroes. Comentario al libro sobre el alma de Aristóteles, S. Gómez Nogales, tr. (Madrid, 1987), 212. Regarding this notion of the Agent Intellect as “form for us,”  see M. Geoffroy, M., “Averroès sur l’intellect comme cause agent et cause formelle et la question de la ‘jonction’ - 1,”  in Averroès et les averroïsmes juif et latin. Actes du colloque tenu à Paris, 16-18 juin 2005, J.-B-Brenet, ed. (Turnhout: Brepols, 2007), 77-110.  Also see “The Agent Intellect as ‘form for us’ and Averroes’ Critique of al-Fârâbî” cited in note 97 and “Intelligibles in act in Averroes,” cited in note 46. In the Middle Commentary he writes, “It is clear that, in one respect, this intellect is an agent and, in another, it is a form for us (ṣûrah la-nâ), since the generation of intelligibles is a product of our will. When we want to think something, we do so, our thinking it being nothing other than, first, bringing the intelligible forth and, second, receiving it. The individual intentions in the imaginative faculty are they that stand in relation to the intellect as potential colors do to light. That is, this intellect renders them actual intelligibles after their having been intelligible in potentiality. It is clear, from the nature of this intellect – which, in one respect, is a form for us (ṣûrah la-nâ) and, in another, is the agent for the intelligibles – that it is separable and neither generable nor corruptible, for that which acts is always superior to that which is acted upon, and the principle is superior to the matter. The intelligent and intelligible aspects of this intellect are essentially the same thing, since it does not think anything external to its essence. There must be an Agent Intellect here, since that which actualizes the intellect has to be an intellect, the agent endowing only that which resembles what is in its substance.” Ibn Rushd, Averroes. Middle Commentary on Aristotle's De Anima. A Critical Edition of the Arabic Text with English Translation, Notes and Introduction, A. L. Ivry, A. L., ed. and tr., (Provo, Utah, 2002), 116.

99 Quoniam, quia illud per quod agit aliquid suam propriam actionem est forma, nos autem agimus per intellectum {500}  agentem nostram actionem propriam, necesse est ut intellectus agens sit forma in nobis. Et nullus modus est secundum quem generetur forma in nobis nisi iste.  Quoniam, cum intellecta speculativa copulantur nobiscum per formas ymaginabiles, et intellectus agens copulatur cum intellectis speculativis (illus enim quod comprehendit ea est idem, scilicet intellectus materialis), necesse est ut intellectus agens copuletur nobiscum per continuationem intellectorum speculativorum. Et manifestum est quod, cum omnia intellecta speculativa fuerint existentia in nobis in potentia, quod ipse erit copulatus nobiscum in potentia.  Et cum omnia intellecta speculativa fuerint existentia in nobis in actu, erit ipse tunc copulatus nobis in actu.  Et cum quedam fuerint potentia et quedam actu, tunc erit ipse copulatus secundum partem et secundum partem non; et tunc dicimur moveri ad continuationem.

Et manifestum est quod, cum iste motus complebitur, quod statim iste intellectus copulabitur nobiscum omnibus modis.  Et tunc manifestum est quod proportio eius ad nos in illa dispositione est sicut proportio intellectus qui est in habitu ad nos.  Et cum ita sit, necesse est ut homo intelligat per intellectum sibi proprium omnia entia, et ut agat actionem sibi propriam in omnibus entibus, sicut intelligit per intellectum qui est in habitu, quando fuerit continuatus cum formis ymaginabilibus, omnia entia intellectione propria. LCDA{ 499-500; Taylor tr., 399. Emphasis added.

100 . . . intellectus existens in nobis habet duas actiones secundum quod attribuitur nobis, quarum una est de genere passionis (et est intelligere), et alia de genere actionis (et est extrahere formas et denudare eas a materiis, quod nichil est aliud nisi facere eas intellectas in actu postquam erant in potentia), manifestum est quoniam in voluntate nostra est, cum habuerimus intellectum qui est in habitu, intelligere quodcunque intellectum voluerimus et extrahere quancunque formam voluerimus. LCDA {495}; Taylor tr., 395. Et cum invenimus nos agere per has duas virtutes intellectus / cum voluerimus, et nichil agit nisi per suam formam, ideo fuit necesse attribuere nobis has duas virtutes intellectus. “We found that we act in virtue of these two powers of intellect 440} when we wish; and nothing acts except through its form; [so] for this reason it was necessary to ascribe to us these two powers of the intellect.” LCDA 439-440}; Taylor tr., 352.

101 Aristotle, De Anima 417a27: boulêtheis. In his comments on De Anima 3.5, 430a14–17, Averroes writes, Deinde dixit: et intellectus secundum quod facit ipsum intelligere omne. Et intendit / per istum illud quod fit, quod est in habitu. Et hoc pronomen ipsum potest referri ad intellectum materialem, sicut diximus; et potest referri ad hominem intelligentem. Et oportet addere in sermone: secundum quod facit ipsum intelligere omne ex se et quando voluerit. Hec enim est diffinitio habitus, scilicet ut habens habitum intelligat per ipsum illud quod est sibi proprium ex se et quando voluerit, absque eo quod indigeat in hoc aliquo extrinseco. LCDA 437-8}. “Next he said: and … . . the intellect insofar as it makes it understand everything. He means 438} by that what comes to be, which is in a positive disposition. This [latter] pronoun it can be understood to refer to the material intellect, as we said, and can be understood to refer to the human being who is the one understanding. It is necessary to add in the account: insofar as it makes it understand everything in its own right and when it wishes. For this is the definition of a positive disposition, namely, that what has a positive disposition understands in virtue of it what is proper to itself in its own right and when it wishes, without it being the case that it needs something external in this.” Taylor tr., 350.

102 This is discussed in LCDA Taylor tr., introduction, lxxiii; in my “Themistius and the Development of Averroes’ Noetics,” cited in note 51; and my “Intellect as Intrinsic Formal Cause in the Soul according to Aquinas and Averroes,” cited in n. 84.

103 Miles Burnyeat, Aristotle’s Divine Intellect, Milwaukee: Marquette University Press, 2008) [Aquinas Lecture Series], 40. Burnyeat, in contrast to what we see in Averroes, finds the agent intellect or God to be present to the soul by final causality alone.  I will address the details of this problematic account elsewhere.

104 On intrinsic formal cause in Aquinas and Averroes, see my article cited in note 58.

105 In his De unitate intellectus Aquinas rightly notes that the key difficulty is in the conception of the nature of the intelligible in act.  He writes, Sed inquirendum restat quid sit ipsum intellectum. Si enim dicant quod intellectum est una species immaterialis existens in intellectu, latet ipsos quod quodammodo transeunt in dogma Platonis, qui posuit quod de rebus sensibilibus nulla scientia potest haberi, sed omnis scientia habetur de forma una separata. Aquinas, De unitate intellectus, V, ll. 164-170.  “But it remains to inquire into what is the understood intelligible itself.  For if they say that the understood intelligible is an immaterial species / form existing in the intellect, it is unnoticed by them that they have somehow passed over to the teaching of Plato who held that no knowledge can be attained from sensible things but rather that all knowledge is attained from a separate form.” On this issue in Averroes, see my “Intelligibles in Act in Averroes,” cited in note 46.

106 dicimur homines equivoce.  LCDA {495}; Taylor tr., 395.

107 This is discussed at length in LDCA {394-400}.

108 See the discussion above and also note 84.

109 In 2 Sent. d. 17, q. 2, a. 1, sol.

110 Cf. notes 25 and 26 above.

111 Aquinas addresses this issue more fully at In 4 Sent., d. 49, q.2, a.1 in the context of the notion of ultimate human happiness by the blessed in patria being found in seeing God face-to-face. This is discussed briefly in my article, “Intellect as Intrinsic Formal Cause in the Soul according to Aquinas and Averroes,” 217-219, cited in note 84, but requires a more substantial study which I intend to provide in another publication.

112 Unde necesse est, cum hoc quod posuimus quod proportio intentionum / ymaginatarum ad intellectum materialem est sicut proportio sensibilium ad sensus (ut Aristoteles post dicet), imponere alium motorem esse, qui facit eas movere in actu intellectum materialem (et hoc nichil est aliud quam facere eas intellectas in actu, abstrahendo eas a materia). Et quia hec intentio cogens ad ponendum intellectum agentem alium a materiali et a formis rerum quas intellectus materialis comprehendit est similis intentioni propter quam visus indiget luce, cum hoc quod agens et recipiens alia sunt a luce . . . . LCDA {438-9}; Taylor tr., 351.

113 In 2 Sent. d. 17, q. 2, a. 1, sol.

114  In 2 Sent. d. 17, q. 2, a. 1, sol.

115 Later he writes,  [L]icet species intelligibilis qua intellectus formaliter intelligit sit in intellectu possibili istius uel illius hominis, ex quo intellectus possibiles sunt plures, id tamen quod intelligitur per huiusmodi species est unum, si consideremus habito respectu ad rem intellectam, quia uniuersale quod intelligitur ab utroque est idem in omnibus. Et quod per species multiplicatas in diuersis id quod est unum in omnibus possit intelligi, contingit ex immaterialitate specierum, que representant rem absque materialibus conditionibus indiuiduantibus, ex quibus una natura secundum speciem multiplicatur numero in diuersis. Thomas Aquinas, Quaestiones Disputatae De Anima, B.-C. Bazán, ed. (Rome: Commissio Leonina, Paris: Éditions du Cerf, 1996) Q.5, A.3, ad 7.  “Although the intelligible species by which the intellect formally understands is in the possible intellect of this or that human being, on the basis of which there are many possible intellects, nevertheless that which is understood through a species of this sort is one, if we consider it with respect to the thing understood, because the universal which is understood by each is the same in all [human beings].  And that what is one in all can be understood through species multiplied in diverse [human beings] occurs on account of immateriality of the species which represent the thing without the individuating material conditions on the basis of which one nature in species is multiplied in number in diverse [human beings].” For Aquinas these intelligible species as representations and also rationes or intelligible contents are the means by which human beings apprehend the natures of things of the world and not the direct object of human intellectual understanding.

116 For a discusssion of this, see LDCA Taylor, tr., introduction, xix-xlii. Also see Taylor, “Intelligibles in act in Averroes,” cited in n. 46, 117 ff.

117 See Taylor, “Themistius and the Development of Averroes’ Noetics,” cited in n. 51.

118 See note 105.

119 Aquinas in this article of the Commentary on the Sentences confronts the teachings and texts of Averroes and Avicenna on the precise points he viewed as most important for the epistemological questions addressed. However, the foundations of the epistemology of Aquinas developed here can be found worked out in detail by Albert the Great about 1245 when he spelled out in even greater detail and more explicitly how he formed his epistemology out of the teachings of Avicenna and Averroes. The key texts in which Albert displays his dependence on and development of sources from the Arabic tradition are in his De homine, Alberti Magni Opera Omnia 27.2 (Cologne: Ashendorff, 2008) at various points in 402-457. Most important for the crafting of his epistemology is Albert’s systematic misunderstanding of Averroes in which Albert asserts that the material intellect and the agent intellect are powers belonging individually and intrinsically to each human soul and are not separate intellectual substances. At 411.46-53 he cites Averroes regarding this: Item, Averroes: ‘Omnis intellectus in nobis existens habet duas actiones. Quarum una est de genere passionis, et est intelligere; alia de genere actionis, et est abstrahere eas a materia, quod nihil aliud est quam facere eas intellectas in actu postquam erant intellectae in potentia’. Cum igitur unum horum sit intellectus agens et alterum possibilis, uterque istorum intellectuum erit in nobis existens et non separata substantia. Aquinas, however,  always held that Averroes taught a doctrine of two separate intellects, the Agent Intellect and the Material Intellect. Albert later changed his understanding to one similar to that of Aquinas. I will provide a detailed study of the epistemology of Albert in the De homine and its development out of sources from the Arabic tradition in another publication.

120 Edward P. Mahoney, “Aquinas’s Critique of Averroes’ Doctrine of the Unity of the Intellect,” in Thomas Aquinas and His Legacy, David M. Gallagher, ed. (Washington, D.C.: The Catholic University of America Press, 1994) 83-106; see p. 85.

121 Regarding this, see J,-P. Torrell, O.P., “La vision de Dieu ‘per essentiam’ selon Saint Thomas d’Aquin,” View and Vision in the Middle Ages - Micrologus. Nature. Science and Medieval Soceties, V , (Florence: Edizioni SISMEL-Il Galluzzo, 1997), 43-68; reprinted in  J.-P. Torrell, O.P., Recherches Thomasiennes. Études revues et augmentées, (Paris: Vrin, 2000) 177-197. Also see J.-B. Brenet, “Vision béatifique et séparation de l’intellect au début du XIVe siècle. Pour Averroès or contre Thomas d’Aquin?” in Les sectatores Averrois. Noétique et cosmologie aux XIIIe – XIVe siècles, Dragos Calma and Emanuele Coccia, ed., (Freiburger Zeitschrift für Philosophie und Theologie, 53 (2006),  1/2.), 310-342. See 329.  Also see Charles J. Ermatinger’s article, “Giles of Rome and Anthony of Parma in an Anonymous Question on the Intellect,” Manuscripta 17 (1973),  91-115. I intend to provide a detailed study of In 4 Sent., d. 49, q.2, a.1 and Aquinas’s confrontation and use of sources from the Arabic tradition in another publication.

122 In 4 Sent d. 49, q. 2, a. 1, resp. This version is taken from a provisional text provided to me by by Dr. Adriano Oliva, O.P.,  of the Commissio Leonina.

123 Qualiter autem essentia separata possit coniungi intellectui ut forma, sic ostendit Commentator in III De anima: quandocumque in aliquo receptibili recipiuntur duo quorum unum est altero perfectius, proportio perfectioris ad minus perfectum est sicut proportio formae ad suum perfectibile, sicut lux est perfectio coloris cum ambo recipiuntur in diaphano; et ideo cum intellectus creatus, qui inest substantiae creatae, sit imperfectior divina essentia in eo existente, comparabitur divina essentia ad illum intellectum quodam modo ut forma. Et huius exemplum aliquale in naturalibus inveniri potest: res enim per se subsistens non potest esse alicuius materiae forrna si in ea aliquid de materia inveniatur, sicut lapis non potest esse alicuius materiae forma; sed res per se subsistens quae materia caret, potest esse forma materiae sicut de anima patet. Et similiter quodam modo essentia divina, quae est actus purus, quamvis habeat - esse ornnino distinctum ab intellectu, efficitur tamen ei ut forma in intelligendo; et ideo dicit Magister in II dist. II Sententiarum quod unio corporis ad animam rationalem est quoddam exemplum beatae unionis rationalis spiritus ad Deum. Quaestiones disputatae de veritate, Q.8, A.1, 218.208-234.  As J.-B. Brenet points out in an article forthcoming in Arabic Sciences and Philosophy, reference to Averroes regarding this teaching disappears with the Summa contra gentiles where in an early autograph version Aquinas mentioned Averroes but in the final distributed text omitted mention of Averroes. For further detailed discussion of this, see Brenet’s article in Arabic Sciences and Philosophy.

124 I would like to extend my sincere thanks to the conference participants for their valuable comments and discussion of the issues presented in this paper.