Yussef Al Tamimi, 4 April 2015

1. Introduction

Avicenna’s proof of God is regarded as one of the main accomplishments of his philosophy. Through the adaption of Avicenna’s argumentation in Thomas Aquinas’ work, the proof remains at the heart of debates on the existence of God in Western philosophy. In this post, I will discuss Avicenna’s conception of unity that underlies his proof for the existence of God. Many books and articles have been written on Avicenna’s work and the relation of his metaphysics to that of Aristotle. Avoiding writing a mere summary of the existing literature, I will try to provide a clear and self-standing account of how Avicenna’s work built on Aristotle’s ideas and how it relates to the thought of other Muslim philosophers, like Al Fārābī and Averroes. Central to this paper are the secondary works on Avicenna by Jan A. Aersten^[1], Amos Bertolacci^[2] and Stephen Menn^[3]. First, Avicenna’s thoughts on the subject matter of metaphysics will be examined (Section 2). Then, I will discuss the relation between unity and being in Aristotle and Avicenna (Section 3). Finally, I will examine Averroes’ critique of Avicenna (Section 4).

2. The subject matter of metaphysics

2.1 Aristotle on First Philosophy (Metaphysics, Book IV)

It is not possible to talk about Avicenna’s metaphysics without first saying something about the conception of First Philosophy as developed by Aristotle. In the first chapter of Book IV of the Metaphysics, Aristotle formulates the investigation that he takes on in the Metaphysics as a science: “a science which investigates being as being and the attributes which belong to this in virtue of its own nature”.^[4] Aristotle distinguishes this science, which we now know as metaphysics, from special sciences, for instance mathematics, because it is the only science that explores the question what it means to be. Unlike the other sciences, the science of being qua being does not simply assume the existence of things, but asks what it means for them to be. As a result, metaphysics concerns all things, because all things ‘are’. Therefore, the science of being qua being is a universal science.

In addition, Aristotle says that we must grasp the first causes of being qua being. In Book I of the Metaphysics, Aristotle stated that one speaks of wisdom, when one knows the causes of things. If wisdom is the knowing of the ‘why’ of things, then the highest form of wisdom is the one that pertains to “the first principles and causes”.^[5] This is why Aristotle also calls the science of being qua being the ‘First Philosophy’.

After delineating it from the special sciences, Aristotle goes on to specify what the science of being qua being contains. He begins the second chapter of Book IV by saying that “there are many senses in which a thing may be said to ‘be’, but all that ‘is’ is related to one central point”.^[6] We may therefore discern two points about being:

1. Being is said in several ways. This means that being has many meanings. Aristotle explains this by referring to the words ‘healthy’ and ‘medical’. Just like the words ‘healthy’ and ‘medical’ have many meanings, so does ‘being’ have several senses in which it is used. For instance, there is a range of things that can be called ‘healthy’: people, diets, exercise, complexions, etc. Not all of these are healthy in the same sense. Exercise is healthy in the sense of being productive of health; a clear complexion is healthy in the sense of being symptomatic of health; a person is healthy in the sense of having good health. Neither ‘healthy’ nor ‘medical’ nor ‘being’ have a single definition that applies uniformly to all cases. In Aristotle’s words: “So, too, there are many senses in which a thing is said to be (…); some things are said to be because they are substances, others because they are affections of substance, others because they are a process towards substance, or destructions or privations or qualities of substance, or productive or generative of substance, or of things which are relative to substance, or negations of one of these thing of substance itself.”^[7]
2. But being is nevertheless related to one central point. Although being has many meanings, all these meanings are related to one common notion of being. Again, the analogy with the term ‘healthy’ comes in handy. The various senses in which ‘healthy’ were applied in the first point, all have something in common: they refer to one common notion, health. Likewise the things that are called ‘medical’ are all related to the science of medicine. In a similar manner the term ‘being’ has a ‘common notion’. And since there is one science that deals with all healthy things and one science that deals with all medical things, the same applies to being.^[8]

About this common notion, Aristotle says that this notion is primary being: something that is a being in virtue of itself and not in virtue of their relation to other things. These primary beings are called substances. ‘Substance’ is a term that originates from Aristotle’s earlier work, the Categories. According to Aristotle, the universe is ultimately made up of substances. ‘Accidents’ refer to the features of these substances. For instance, when saying ‘a tall person’, ‘person’ is the substance, and ‘tall’ is the accident. It is possible for the person (which is the substance) to exist without that accident. However, no accident can exist unless a substance exists for it to be in. Tall is, but it can only be because the person is. Therefore, the existence of a substance is prior to that of accidents. According to Aristotle, science deals chiefly with that which is primary^[9], therefore metaphysics deals chiefly with the being of substances. Moreover, next to studying being qua being, it is the work of metaphysicians to explore the species of being.^[10]

2.2 Avicenna on the subject matter of metaphysics (The Metaphysics of The Healing, Book I)

As pointed out by Aertsen, the determination of what Aristotle regarded as the subject of First Philosophy remains a controversial issue among scholars today.^[11] Avicenna starts the second chapter of Book One of The Metaphysics of The Healing with this question. Avicenna states that every philosophical science has its own subject. Either this subject (i) arises from our action or (ii) it exists independently from us.^[12] In the first case, it is a practical science, and in the second case, it is a theoretical or speculative science. For Avicenna, there are three practical sciences (politics, economics and ethics) and three theoretical science: physics (the natural science), mathematics and metaphysics (ilāhiyyāt) (the divine science; al ^cilm al ilāhī).

Avicenna then discusses three things that might be the subject matter of metaphysics. The first possibility is that God is the subject matter. Avicenna discards this possibility, because metaphysics is the study that must demonstrate his existence rather than presuppose and study his existence. Even though metaphysics discusses God, it cannot claim God as its subject.^[13] The second possibility Avicenna mentions as the subject matter of metaphysics are the first causes.^[14] For similar reasons as God, first causes cannot be the subject of the divine science, because it is the task of metaphysics to demonstrate their existence.

In the second chapter of Book One of The Metaphysics of The Healing, Avicenna solves the problem of the subject matter of metaphysics by stating that the subject matter is being qua being (al mawjūd bi-mā huwa mawjūd), which is being that is common (mushtarak) to all things that are.^[15] Avicenna comes to this conclusion by comparing the subject of metaphysics to that of the other theoretical sciences. He argues that physics does not study objects as beings, but as objects subject to movement and rest. Similarly, mathematics studies measure and number; objects whose accident is mathematical. Therefore, in both these sciences, being is presupposed rather than studied for itself. Metaphysics, on the other hand studies being qua being, understood as being that is common to all things that are. Moreover, metaphysics investigates all that is unconditionally related to being qua being. Avicenna states:

“The primary subject matter of this science is, hence, the existent inasmuch as it is an existent; and the things sought after in [this science] are those that accompany [the existent,] inasmuch as it is an existent, unconditionally.”^[16]

This reminds of Aristotle’s opening sentence in Book IV of the Metaphysics: “There is a science which investigates being as being and the attributes which belong to this in virtue of its own nature”.^[17] According to Avicenna, the ‘things’ that accompany being qua being unconditionally, and are therefore studied in metaphysics, are, first of all, the categories that are the species of being, namely: substance, quantity and quality.^[18] These categories all pertain to being in general. Secondly, metaphysics encompasses the things that are to be regarded as the accidents of being, such as the one and the many, the potential and the actual, the universal and the particular, and the possible and the necessary.^[19]

2.3 The primary impression (al irtisām al awwali) (The Metaphysics of The Healing, Book I)

Avicenna continues by saying that being is “impressed in the soul in a primary way (tartasim irtisāman awwaliyyā)”.^[20] Avicenna here introduces being as a primarily impressed notion. In the fifth chapter of Book One of The Metaphysics of The Healing, Avicenna expands on the doctrine of primary notions, among which are also ‘the thing’ (al shay’) and ‘the one thing’ (al shay’ al wāhid). These are notions that are all impressed in the soul in a primary way:

“We say: The ideas of “the existent,” “the thing,” and “the necessary” are impressed in the soul in a primary way.”^[21]

“The things that have the highest claim to be conceived in themselves are those common to all matters – as, for example, “the existent,” “the one thing,” and others.”^[22]

Aertsen discusses the doctrine of primary notions by asking why it is necessary for Avicenna to accept primary notions.^[23] The basis of Avicenna’s argument for the primary notions is an analogy between two orders of knowledge, the order of assent (tasdīq) and the order of conception (tasawwur). Tasawwur concerns the incomplex knowledge of concepts (tasawwurāt), such as “stone” and “tree”; tasdīq concerns the knowledge of propositions, such as “the world has a beginning”.^[24] Avicenna claims that in both orders a reduction to first principles that are known per se is necessary. Just as there are first principles that are known through themselves in the order of tasdīq, there are also principles that are conceived in themselves and do not require any prior conception in the order of tasawwur. Avicenna says:

“Similarly, in conceptual matter, there are things which are principles for conception that are conceived in themselves.”^[25]

The basis of this analysis goes back to Aristotle. In Posterior Analytics, Aristotle had argued that science is grounded knowledge. Science is the conclusion that is inferred from propositions that are previously known. Therefore, it is always derived from something prior. This structure, however, could lead to an infinite regress in search of the ultimate foundation of science. Aristotle solves this problem by concluding that the first principles of science cannot be demonstrated; the first principles of science are not derived from something else, but are immediately known.^[26]

This is where Avicenna adds an original turn to Aristotle’s reasoning: he applies the same finite structure of science (tasdīq) to the order of concepts (tasawwur). Just as propositions must be reduced to first indemonstrable principles, there must be primary notions in the order of conception:

“If every conception were to require that another conception should precede it, then such a state of affairs would lead either to an infinite regress or to circularity.”^[27]

The originality of Avicenna therefore stems in that he applied Aristotle’s finite structure to the order of tasdīq as well as to the order of tasawwur. This allowed him to qualify notions such as ‘the existent’, ‘the thing’ and ‘the one thing’ as primary notions that are ‘impressed on the soul’, and were therefore the first known conceptions to man; they were not preceded by previous concepts.

2.4 Essence and existence (The Metaphysics of The Healing, Book I)

Aertsen notes that the addition of ‘thing’ on the list of Avicenna’s primary notions is an important one.^[28] Every ‘thing’, Avicenna states, has a reality (haqīqa) through which it is what it is. For instance, a triangle has a reality in that it is a triangle and whiteness has a reality in that it is whiteness.^[29] The reality of a thing is called its ‘proper existence’ (al wujūd al khās). In the concluding summary of his account, Avicenna describes the reality of a thing as its ‘quiddity’ (māhiyya). He states that every thing has quiddity, and that this is something different than the thing’s existence:

“It is evident that each thing has a reality proper to it – namely, its quiddity. It is known that the reality proper to each thing is something other than the existence that corresponds to what is affirmed.”^[30]

This is the important doctrine in Avicenna’s work that is known as the distinction between essence and existence. Essence signifies the proper existence, al wujūd al khās, of a thing, while existence means the existence that corresponds to what is affirmed, the ‘affirmed existence’, or al wujūd al ithbāti. Aertsen remarks that essence is not a new concept, but what is original about Avicenna’s approach, is that he distinguished essence (res) from existence (ens):

“The Avicennian “thing” is related to the certitudo of a thing, it signifies its “whatness”. Res expresses the Greek tradition of intelligibility, which centres on the quiddity of a thing by posing the question as to what it is. What is new in Avicenna’s account is not the introduction of res, but rather the conceptual differentiation between res and ens, which signifies that something is. This differentiation seems to be related to the questions “whether something is” (an est) and “what it is?” (quid est), but its basis is an ontological difference that is fundamental to Arab metaphysics, namely the distinction between “essence” and “existence”.”^[31]

For Avicenna, being is a necessary concomitant (mutalāzim) of ‘thing’, but is not identical with it, because the two notions have different meanings.^[32] For instance, when one says “a horse exists”, one is not simply saying “a horse is a horse”.^[33] To say “a horse is a horse” is to say that X is what it properly is, namely, X. It is X’s proper being, its essence, to be so. On the other hand, to say “a horse exists” is not the same as saying that it is X. To say “a horse exists” is saying that it exists in the sense of al wujūd al ithbāti; it addresses a thing’s affirmed existence (that it is, not what it is). Essence does not include the idea of (affirmed) existence. Therefore, for a thing to exist, existence must be added to the essence of the thing. Nevertheless, Avicenna holds that being is a necessary concomitant of thing, because it would be meaningless to use the term ‘thing’ if existence is not necessarily associated with it.^[34] Avicenna therefore states:

“Hence, you have now understood the way in which “the thing” differs from what is understood by “the existent” (…) and that, despite this difference, the two [that is, “the thing” and “the existent”] are necessary concomitants.”^[35]

Existence is, therefore, not a defining characteristic of essence; from what a thing is, it cannot be inferred that it exists. Existence is an accident of essence, something that is added to essence when a thing is said to exist.^[36] This allows Avicenna to argue for the idea that we can sometimes correctly say that “a thing is not” or falsely say that “a thing is”, because existence and a thing’s essence should be regarded as two seperate. All things have ‘thingness’ (shay’iyya), but they do not all exist. This point becomes central in the discussion of fifth chapter of Book One of The Metaphysics of The Healing, where Avicenna rejects the mu^ctazilite notion that ‘nonexistence’ is a thing.^[37] This discussion with the mu^ctazilites revolves around the following Qu’ranic passage:

“When Allāh wishes to create a thing (shay’an), he says to it ‘be!’ (kun) and it is (fayakūn)”^[38]

In explaining this Qur’anic passage, the mu^ctazilites, created a domain of non-existing objects (ma^cdūmāt). The reasoning was that, since there is some shay’ that God wishes to create and still does not exist, there must be a domain of non-existing objects. This mu^ctazilite conclusion was resisted by most non-mu^ctazilites, including Avicenna, partly on the ground that it seems to posit objects which are independent of God’s creative activity.^[39] How, then, do the non-mu^ctazilites make sense of the mentioned Qur’anic passage?

2.5 Al Fārābī on nonexistence

For a large part, Avicenna’s reaction to the mu^ctazilites was based on Al Fārābī’s response. To solve the nonexistence problem, Al Fārābī makes a distinction between two main senses of being:

• The first sense is being as divided into the categories, which is being that is “delimited by an essence outside the soul”. In this sense, to say that X is a being is to predicate X’s own essence of it. The existence of X will be just the essence of X, and not anything distinct from it. Being in this sense will be predicated primarily of substances, derivatively of things in accidental categories, but not of things which are not species of any category.^[40]
• The second sense of being is being as the true, which is defined by Al Fārābī as “what is outside the soul as it is inside the soul”. In this sense, the concept of X is true, i.e. it “is outside the soul as it is inside the soul”, if it is instantiated by something outside the soul. X can be a being in this sense even if it has no real essence, since the concept of not-white or blindness or white horse can still be instantiated. Being-as-the-true, therefore, applies univocally to things in all categories and to things in no category at all.^[41]

Al Fārābī argues that when we ask whether X is, we must be asking whether X is a being in the second, univocal sense of being-as-the-true, since we do not yet know what X is, and so do not know what category X is in, or whether it is in any category at all. This allows Al Fārābī to conclude that because being in this sense, being-as-the-true, is predicated of things in the soul, it is a ‘secondary intelligible’ and not something really existing outside the soul.^[42] It also allows him to explain how we can truly assert a sentence like “phoenixes do not exist”, or falsely but meaningfully assert “phoenixes exist”, without appealing to the non-existing objects (ma^cdūmāt) of the mu^ctazilites. This is because a fictional entity like a phoenix refers to a concept, but only to a mental concept of a phoenix, not something really existing outside the soul.^[43]

2.6 Avicenna’s response to the mu^ctazilites (The Metaphysics of The Healing, Book I & IX)

Avicenna gives a non-mu^ctazilite solution which sounds close to Al Fārābī’s response, but he ultimately adopts an importantly different position than Al Fārābī. Avicenna denies the mu^ctazilite view that there are things which are non-existent (ma^cdūm) without restriction. In the fifth chapter of Book One of The Metaphysics of The Healing, he says that although things may be non-existent outside the soul (in external reality; fī al a^cyān), they must exist at least in the soul (or mind; fī al dhihn), or else nothing could be said about them:

“If by the nonexistent is meant the nonexistent in external reality, this would be possible; for it is possible for a thing that does not exist in external things to exist in the mind. But if [something] other than this is meant, this would be false and there would be no information about it at all. It would not be known except only as [something] conceived in the soul. [To the notion] that [the nonexistent] would be conceived in the sould as a concept that refers to some external thing, [we say] “Certainly not!” (…) [This is] because our saying “it” entails a reference, and reference to the nonexistent that has no concept in any respect at all in the mind is impossible.”^[44]

Avicenna resembles Al Fārābī in that he distinguishes two senses of being. Avicenna’s wujūd al ithbāti (affirmed existence) corresponds to Al Fārābī’s ‘being as truth’, and al wujūd al khās (proper existence) corresponds to ‘being as divided into the categories’.^[45] But, unlike Al Fārābī, Avicenna does not say that al wujūd al ithbāti is a ‘secondary intelligible’, something depending on and existing in the soul. On the contrary, Avicenna thinks that being in this sense, wujūd ithbāti, is an objective feature of things. As mentioned above (see paragraph 2.4), the wujūd al ithbāti of a thing is a necessary concomitant of the essence of a thing, which would be absurd, according to Avicenna, if it would be a secondary intelligible.^[46]

But how can Avicenna maintain this, when he agrees with Al Fārābī that the mu^ctazilite non-existent objects (ma^cdūmāt) are things existing in the soul? The key, for Avicenna, is that the essence of these things is neutral to either existing in the soul as a concept or existing outside the soul. It is not the concept which is capable of existing outside the soul; rather, the essence, which exists in the soul as a concept, can also exist outside the soul.^[47]

This, then, is Avicenna’s solution to the problem that the abovementioned Qur’anic passage poses: all the things did indeed exist – as mental concepts in the soul. However, this raises a question: does this mean that God had all these essences in his mind before he created them? If so, would this not imply multiplicity and change in God, and thus violate the Islamic doctrine of the absolute oneness and uniqueness of God?

Avicenna addresses this problem in the fourth and fifth chapter of Book Nine of The Metaphysics of The Healing and argues that he can avoid these consequences. Creation, according to Avicenna, is a complex process, taking its starting point from God. Even though God is the ultimate cause of everything, He does not directly bring about multiplicity. According to Avicenna, this would be a contradiction:

“For then there would be something in Him by reason of which He intends – namely, His [direct] cognizance and knowledge of the necessity of intending, or a deference to it, or a goodness therein that necessitates it. Then [there would be knowledge in Him] of the intention [itself], then of a benefit the intention would bestow on Him (…) – [all] this being impossible.”^[48]

Instead, Avicenna argues that God must be a true intellect whose “first and essential act (…) is to intellectually apprehend His [own] essence, which in itself is the principle of the order of the good in existence”.^[49] This act of God is the cause of existence for everything else that comes into being. It’s coming into being is by necessity, due to the necessity of God’s existence.

3. Unity and being

In the previous chapter, I have shown how Avicenna argues that existence can be considered as an accident of essence. According to Avicenna, essence considered simply as an essence, excludes not only existence, but also unity and plurality.^[50] Moreover, he maintains that universality and particularity are accidents of essence.^[51] In short, essence as such excludes existence, unity, plurality, particularity and universality. In this chapter, I will discuss in more detail Avicenna’s view on the relation between unity and being. For this, I will first turn to Aristotle’s conception of unity.

3.1 Aristotle on unity and being (Metaphysics, Book IV & X)

In the second chapter of Book IV of the Metaphysics, Aristotle states the following on the similarity between being and unity:

“Being and unity are the same and are one thing in the sense that they are implied in one another (…), not in the sense that they are explained by the same definition”.^[52]

There is a distinction, therefore, between the definition and the nature of these two concepts. With regard to the definition of being and one, Aristotle states that the definition of ‘one’ is ‘indivisible’. One thus adds a negation to being and, therefore, the two notions do not have the same definition.^[53]

With regard to the similar nature of being and one (‘they are implied in one another’), Aristotle gives two arguments for this similarity. Firstly, he illustrates the similarity by saying that ‘one man’ and ‘man’ are considered the same thing, and so are ‘existent man’ and ‘man’. Therefore, unity and being, in this sense, are convertible. Secondly, being and unity are both implied in all substances. As mentioned above, according to Aristotle, the universe is ultimately made up of substances, and accidents refer to the features of these substances. According to Aristotle, “the substance of each thing is one in no merely accidental way, and similarly is from its very nature something that is”.^[54] Hence, being and unity are both implied in all substances, and are not accidents.

From these arguments, Aristotle concludes that there must be exactly as many species of being as of unity.^[55] Just as ‘being’ is said in several ways and thus has many meanings (see paragraph 2.1), so does ‘one’. Therefore, the examination of the essence of being and unity, according to Aristotle, is the work of the same science: metaphysics.

The discussion of unity leads into a discussion of contrariety. Aristotle notes that opposites are dealt with by the same science. Since unity and plurality are opposites, this means that unity and plurality are both subjects of the same science. Therefore, metaphysics discusses both unity and plurality, together with the species of plurality, which Aristotle names as the other, the dissimilar and the unequal. And since contrariety is a sort of otherness, it also falls under the scope of the science that examines plurality.^[56]

In the first chapter of Book X of the Metaphysics, Aristotle expands on the different meanings of ‘one’. The four meanings of ‘one’ are:

Things that are ‘one’ as a quality:

1. Something that is continuous, especially the things that are continuous by nature.
2. That which is a whole and has a certain shape and form. A thing is of this sort if its movement is one and indivisible in place and time.

Two meanings of ‘one’ where the definition of the thing is one:

1. That which is indivisible in number.
2. That which (in intelligibility and in knowledge) is indivisible in kind.

What is common to all these meanings, is that that which is one is indivisible, either absolutely (as a quality) or qua one (as a quantity).^[57] However, Aristotle states in the second chapter of Book X that unity itself is not a substance. This is for two reasons. First, unity, like being, is a universal, and universals themselves cannot be substances. They universally apply to all substances, but are not themselves substances. Second, unity is always a property of something else: there is one table, one person, one chair, but never the number one by itself (one ‘one’).^[58] Therefore, one is not a substance itself.

3.2 Avicenna on unity and being (The Metaphysics of The Healing, Book III, V & VII)

Next to ‘being’ and ‘thing’, Avicenna lists unity among the primary notions. Recall that in Book One of The Metaphysics of The Healing, Avicenna listed ‘the one thing’ (al shay’ al wāhid) as one of the primary notions.^[59] In Book Three, Avicenna affirms that unity (al wahda) is also a primary notion:

“Here, unity is taken as conceived in itself and as one of the first principles of conception.”^[60]

In Book Three of The Metaphysics of The Healing, Avicenna makes three statements with regard to the relation between being and unity:

1. First, the ‘one’, like ‘being’, is said of each of the categories.^[61] This is the same idea as asserted by Aristotle regarding the convertibility of being and unity.^[62]
2. The first statement does not mean, however, that the definition of unity and being are identical.^[63] Again, this is also what Aristotle meant by saying that being and the one are not determined by one concept. Avicenna illustrates the conceptual difference between ‘one’ and ‘being’ by pointing out that the many as many is not one, but is nevertheless a being. He says: “[Now,] everything has one existence. For this reason, it is perhaps thought that what is understood by both is one [and the same]. But this is not the case. Rather, the two are one in subject – that is, whatever is described by the one is described by the other. If it were the case that what is understood by one is in all respects the same as what is understood by the existent, then the multiple inasmuch as it is multiple would not exist, as it is not one – [this] even though the one also occurs to it accidentally, so that it is said of multiplicity that it is one multiplicity, though not inasmuch as it is multiplicity.”^[64]
3. Finally, Avicenna argues neither ‘being’ nor ‘one’ designates the substance of any thing.^[65]

The first two features – the convertibility and conceptual difference – are adopted from Aristotle’s account of unity in book IV of the Metaphysics. The third characteristic is non-Aristotelian and is rooted in Avicenna’s original distinction between essence and existence discussed in paragraph 2.4. According to Avicenna, unity does not enter into the definition that determines the essence of a thing. Like being, unity is a necessary concomitant of essence. Consequently, and also like being, unity is an accident of essence.^[66]

All in all, for Avicenna, being and unity are both not contained in the essence of a thing. The same is true for particularity and universality; an essence is not in itself particular or universal.^[67] Therefore, the essence of, for example, ‘horseness’ (al farasiyya) has one kind of existence in an individual horse, another kind of existence as a universal in someone’s mind, but both kinds of existence – individual and universal – are added attributes, i.e. accidents, to the essence of horseness.^[68] Neither unity nor multiplicity, neither particularity nor universality belong to the essence considered purely in itself, and this is why none of these are mentioned in the definition of horseness:

“For, in itself, it is nothing at all except “horseness”; for, in itself, it is neither one nor many and exists neither in concrete things nor in the soul, existing in none of these things either in potency or in act, such that [these] are included in “horseness.” Rather, in terms of itself, it is only “horseness.””^[69]

According to Bertolacci, the distinction between essence and existence thus becomes a kind of theoretical tool for Avicenna by means of which he can elucidate the principles of universals.^[70] The distinction functions as a pattern of investigation which leads Avicenna to conclude that universality and particularity attach themselves as accidents to an essence.

3.3 Essence and universality (The Metaphysics of The Healing, Book V)

Abstracting essence from unity, particularity, universality etc. and then considering them all as attributes of essence, thus allows Avicenna to reiterate his main point that essence is distinct from all modes of existence. However, this might open up Avicenna’s theory to the argument that, in Avicenna’s thinking, the essence of horseness must be considered as a universal essence present in each individual horse. Avicenna’s view, however, is different. This issue becomes central in Book Five of The Metaphysics of The Healing.

Avicenna’s argument is based on an analysis of how phrases like ‘animality inasmuch as it is animality’ (al hayawāniyya bi-mā hiya hayawāniyya, or animality qua animality) or ‘humanity inasmuch as it is humanity’ (al insāniyya bi-mā hiya insāniyya, or humanity qua humanity) function semantically.^[71] Assume that the sentence “horseness, inasmuch as it is horseness, is A” is wrong. From this, Aristotle says we may not infer “horseness, inasmuch as it is horseness, is not A”, but only “it is not the case that horseness, inasmuch as it is horseness, is A”.^[72]

Avicenna applies the same logic to the following question: “Is the humanity of Zayd, inasmuch as it is humanity, [something] other than the one of Amr?”.^[73] The answer to this question is no. However, we cannot infer from this answer that the humanity which is in Zayd, inasmuch as it is humanity, is the same object that is also in Amr (or, in Avicenna’s terms, “it does not follow that he should say, “That [humanity] and this [humanity] are numerically the same””^[74]). We can only infer that the fact that it is humanity, does not make the humanity which is in Zayd to be other than the humanity which is in Amr. The humanity which is in Zayd is not the same as the humanity which is in Amr, because humanity has contrary accidents in the two individuals. But it’s being different is something ‘extraneous to’ (shay’un min khārij) the essence of humanity, since the accidents cause the difference, and these accidents are not part of the definition of the essence of humanity.^[75]

Avicenna also uses this line of reasoning to respond to the objection that an essence cannot exist in individuals. The objection says:

“Someone, however, may say: “Animal inasmuch as it is animal does not exist in individuals. [This is] because that which exists in individuals is a certain animal, not animal inasmuch as it is animal. Moreover, animal inasmuch as it is animal exists. It is, hence, separate from individuals. If animal inasmuch as it is animal were to exist in this individual, then it either belongs specifically to it or not specifically. If it belongs specifically to it, then animal inasmuch as it is animal would not be that which exists in it, or that which is identical with it, but [would] be a certain animal. If it were not to belong specifically to it, then a thing numerically one and the same would exist in plurality, and this is impossible.””^[76]

In other words, the objection goes that animal inasmuch as it is animal does not exist in, for instance, Zayd, since neither is it particular to Zayd (for what is particular to Zayd would be an animal, not animal inasmuch as it is animal), nor is it common to Zayd and Amr (for then a numerically single thing would exist in many and would have contrary attributes, which is impossible). Therefore, since animal inasmuch as it is animal exists, it must be separate from the individuals.

Avicenna responds by saying that animal inasmuch as it is animal is neither particular nor universal.^[77] Avicenna makes a distinction between animal inasmuch as it is animal “without the condition of some other thing” (bi-lā sharti shay’in ākhar) and animal inasmuch as it is animal “with the condition that there is no other thing” (bi-sharti lā shay’in ākhar).^[78] The latter, animal inasmuch as it is animal with the condition that there is no other thing, exists only in the soul. If it existed outside the soul, it would be a Platonic Form of animal, and Avicenna obviously rejects this.^[79] On the other hand, animal inasmuch as it is animal without the condition of some other thing can exists in an individual. For in this sense, essence is in itself without the condition of another thing, even though when it exists, for instance, in Zayd, ‘a thousand conditions’, i.e. countless attributes, might attach to it.^[80] Therefore, an essence can exist in individuals.

4. Averroes’ critique of Avicenna

The most famous critic of Avicenna’s philosophy was Averroes. In this chapter, I will examine his critique of Avicenna’s metaphysics. First, his critique on Avicenna’s view on the subject matter of metaphysics will be discussed. Then, Averroes’ view on the distinction between essence and existence will be examined. Finally, I will discuss his critique on Avicenna’s conception of unity.

4.1 Critique on Avicenna’s view on the subject matter of metaphysics

Firstly, Averroes criticized Avicenna for his view on what the subject matter of metaphysics is. Recall that Avicenna concluded that being qua being is the subject matter of metaphysics. Averroes claims that God and all immaterial beings are the correct subject matter. This disagreement between Avicenna and Averroes embodies the tension between the ontological (Being as the subject matter) and theological (that which is beyond physics as the subject matter) determinations of metaphysics.^[81]

The basis of Averroes’ objection is the principle that no science can demonstrate its own subject. Avicenna uses this principle to show that God cannot be the subject matter of metaphysics (or, as Avicenna also called it, the ‘divine science’), since God’s existence has to be demonstrated in this science. According to Averroes, Avicenna was wrong with regard to the place of the proof for God’s existence. In his book Epitome of the Metaphysics, which preceded his more well-known work Tahāfut al Tahāfut, Averroes argues that there is no way to demonstrate the existence of a First Principle, except by motion.^[82] However, metaphysics only deals with the formal and final causes, while it is physics that deals with material and efficient causes and establishes what its principles are. Therefore, physical principles such as the existence of the First Mover should be dealt with in physics and not in metaphysics:

“It is [Aristotle’s] basic aim in this science to state that which remains [to be stated] scientifically with respect to the knowledge of the most remote causes of sensible things, because that which has been shown in this respect in physics are only two remote causes, namely the material and the moving [causes]. What remains to be shown here [in metaphysics] are their formal and final causes (…). Therefore, he who practises this science [of metaphysics] takes for granted the existence of the [first mover] from physics, as said before, and states [only] the mode in which it is the moving [cause].”^[83]

Hence, metaphysics relies and builds on the principles that are established by physics. In other words, the proof for the existence of the Prime Mover – which is established by physics – is the necessary precondition of the possibility of metaphysics. Any other proof for the existence of the Prime Mover without taking into account the facts of physics, such as the one Avicenna wants to give in his metaphysics, does not amount to a valid demonstration:

“The demonstrations employed by Ibn Sīnā in this science [of metaphysics] in order to show [the existence] of the first principle are (…) altogether dialectical and untrue propositions, which do not state anything in an appropriate manner.”^[84]

Therefore, Avicenna was wrong in that he tried to prove the existence of God in metaphysics. For Averroes, metaphysics studies God and hence presupposes His existence. Averroes therefore supports the ‘theological’ conception of metaphysics and holds that the study of the highest being, which is the first form and the ultimate end, includes the study of all other beings.^[85]

4.2 Critique on the distinction between essence and existence

A major innovation in Avicenna’s metaphysics is that he distinguished essence from existence. He regards existence as a necessary concomitant of essence, but the two have different meanings:

“Hence, you have now understood the way in which “the thing” differs from what is understood by “the existent” (…) and that, despite this difference, the two [that is, “the thing” and “the existent”] are necessary concomitants.”^[86]

Averroes strongly opposes this distinction and argues that existence cannot be regarded as an accident of essence. In Epitome of the Metaphysics, Averroes starts his discussion on being (mawjūd) by saying that there are two main philosophical meanings of being.^[87] Being can be used to refer to that which exists outside the soul and to that which is true. In the latter case, being is something that exists inside the soul that corresponds with what exists outside the soul. Of course, this reminds strongly of Al Fārābī’s distinction between being as divided into the categories and being-as-the-true (see paragraph 2.5).

According to Averroes, the philosophical meaning of being has to be distinguished from how being is understood by ‘the masses’. For common people, Averroes says, the word mawjūd gives the idea of something that is in a subject, and so it seems to point to an accident rather than to an essence:

“The meaning it has in [the language of] the masses is different from what it signifies here [in philosophy], as it signifies among the masses merely a certain [accidental] disposition, as when one says that a stray animal ‘has been found’. In short, among them it signifies something in a substrate [the meaning of] which is not quite clear. Therefore, some of them thought that [the term] signifies not the essence of a thing, but rather an accident in it, because it is [used] in [the language of] the masses [like] derived [forms of] words.”^[88]

Due to the fact that the Arabic word mawjūd has been derived from ‘found’ (‘has been found’ translates into mawjūd, the root of which is wajada)^[89], Averroes claims that people are tricked into thinking that being involves an underlying subject, i.e. that being in this sense refers to being-as-the-true. Hence, these people mistakenly regard being as an accident of essence. Although Averroes does not mention Avicenna explicitly in this paragraph, his criticism is most probably directed toward Avicenna.^[90]

Averroes’ next paragraph contains a refutation directed explicitly to Avicenna:

“Furthermore, if [‘being’] signifies an accident in a thing, as stated repeatedly by Ibn Sīnā, one of the [following] two cases must apply to it: this accident is either one of the second intentions or one of the first intentions. If it is one of the first intentions, it is necessarily one of the nine [accidental] categories, and [consequently] the term ‘being’ cannot apply to the substance and the remaining categories of the accident, unless this [mode of] predication is somehow accidental to [all of] them or there is one genus of accidents common to [all] ten categories. But all this is absurd and unacceptable. According to this [doctrine], if one were asked what each of the ten categories contains, it would be incorrect to answer [“being”], but all this is self-evident.

On the other hand, if it is [conceived as] one of the second intentions (that is, intentions which exist only in the mind), nothing prevents us from [holding] this [doctrine of the accidentality of being], for this meaning is one of [the ones] we enumerated, to which the term ‘being’ applies, namely that which is synonymous with the true. However, this meaning and the meaning by which this [term] signifies the essences individually are entirely distinct.”^[91]

Averroes sets up his argument against Avicenna’s view using the notions of primary and secondary intelligibles. He states that, if being is an accident, it has to be either (1) a primary intelligible or (2) a secondary intelligible. As mentioned above (see paragraph 2.5), a primary intelligible is something that is realized in the mind out of a real, perceptible thing; it thus implies counterparts in and outside the mind. Secondary intelligibles only exist concomitantly with primary intelligibles after the latter are realized. They do not have counterparts in reality outside the soul.

If being is a primary intelligible, Averroes says, there are two possibilities: (1a) either being would have to be one of the nine accidental categories or (1b) being would have to be a genus of accident common to all ten categories (substance and the nine accidental categories). According to Averroes, option (1a) is impossible, because if being were one of the nine accidental categories, then it would not be possible to predicate it of the category of substance (or of any other accidental categories except insofar as they are affected by the category of which being is predicated). In other words, we would lose that meaning of being that relates to essence, being qua being.^[92]

Option (1b) is impossible as well. Averroes argues that, under this position, “if one were asked what each of the ten categories contains, it would be incorrect to answer [“being”]”. In other words, when dealing with the categories, the accidental meaning of being that Avicenna posits cannot be given as the answer to question “What is?”.^[93] Averroes does not elaborate on this point, but Nájera points out that this view originates from Aristotle. Being (and unity also for Aristotle) cannot be the genus of things in general, because the differentiae of any genus must have being and we cannot predicate the genus of the differentiae taken apart from the species.^[94]

So if being signifies an accident, the only possibility left is that it is a second intelligible, i.e. an intelligible whose existence is only in the soul. Here no (logical) problem would arise, Averroes states, because being would then simply correspond to the second meaning of being mentioned above, namely being-as-the-true. However, this sense is different from the first meaning which is applicable to essences (being as that which exists outside the soul). Averroes simply wants to remark that the meaning of being-as-the-true is not as relevant as the first meaning, because it concerns something that only exists in the mind.^[95]

The critique given by Averroes in his later work Tahāfut al Tahāfut is slightly different from the one given in Epitome of the Metaphysics. In Discussion 5 of Tahāfut al Tahāfut, Averroes repeats that there are two main meanings of being.^[96] However, instead of laying out the possible positions that Avicenna could take, Averroes simply asserts that Avicenna’s view implies that being is something common to the ten categories (option 1b). Averroes then refutes this position in a different way than in Epitome of the Metaphysics. He argues that the case implies an infinite regress:

“The theory that existence is an addition to the quiddity and that the existent in its essence does not subsist by it—and this is the theory of Avicenna—is a most erroneous theory, for this would imply that the term ‘existence’ signified an accident outside the soul common to the ten categories. And then it can be asked about this accident when it is said to exist, if ‘exist’ is taken here in the meaning of the ‘true’ or whether it is meant that an accident exists in this accident, and so on ad infinitum, which is absurd.”^[97]

Put succinctly, Averroes contends that to say that existence is an accident is also to say that existence itself exists (as an accident). Avicenna’s position thus implies a regression ad infinitum, which is absurd. In Discussion 7 of Tahāfut al Tahāfut, Averroes repeats his diagnosis of the source of Avicenna’s error, namely that Avicenna thought that the word mawjūd indicated an accident in Arabic and that it only referred to being-as-the-true. Being-as-the-true, however, only indicates a secondary intelligible. The source of this error is, as mentioned above also, that the Arabic mawjūd is derivative in form (a paronym), because the translators of the Greek philosophy into Arabic could not find a better term.^[98]

4.3 Critique on Avicenna’s conception of unity

With unity, as with being, Averroes’ aim is to show that Avicenna was wrong in his claim that unity is accidental to the essence of things. Recall that, for Avicenna, neither unity nor multiplicity, neither particularity nor universality belong to essence, and this is why none of these are mentioned in the definition of, for example, horseness:

“For, in itself, it is nothing at all except “horseness”; for, in itself, it is neither one nor many and exists neither in concrete things nor in the soul, existing in none of these things either in potency or in act, such that [these] are included in “horseness.” Rather, in terms of itself, it is only “horseness.””^[99]

Averroes’ response to Avicenna on unity is parallel to his response in the case of being. According to Averroes, Avicenna again confused the common notion of numerical unity with the correct metaphysical meaning of the term, and thus believed that unity only designated an accident in a substance. In ordinary usage, unity is understood in the sense of the numerical ‘one’.^[100] Something is called one in number if it is continuous. It is also called one if it is composed of several juxtaposed homoeomerous bodies bound together in such a way that they all move together when any of them is moved. Finally, an individual thing in form, like Socrates, is also called one.^[101] Overall, Averroes states, common people call things one in number only inasmuch as they are isolated (munhāz) from other things:

“[In the language of ] the masses, ‘one’ generally signifies such things only inasmuch as they are isolated from other things and set apart by their essence and inasmuch as they are indivisible. [This is so] because these are precisely [the things] one conceptualizes straightaway, from [considering] the meaning of ‘oneness’ and ‘one’.”^[102]

Avicenna was misled by this ordinary-language use of ‘one’ and overgeneralized to the conclusion that every numerical unity^[103], i.e. every isolation (inhiyāz), is an accident of the thing which is one.^[104] Averroes argues that, in metaphysics, a different meaning of ‘one’ is used, namely the meaning that is synonymous to a thing’s essence:

“While the masses do not know any further meaning of ‘one’, it is employed in this discipline [of metaphysics also] as a synonym of the thing’s essence and quiddity. [Predicated] in this way, the numerical one might signify the individual which does not admit of division in so far as it is an individual, as when we say ‘one man’, ‘one horse’.”^[105]

Next to the example of one man and one horse, Averroes uses the example of oxymel (a blend of honey and vinegar, used as a medicine) to clarify his position. Although oxymel is an individual unity in the sense that it is isolated from other things, the honey is still considered as one thing and the vinegar is also considered as one thing. What makes the honey in oxymel one thing, and the vinegar in oxymel one other thing, is that each possesses, and is isolated from the other by, its own intrinsic nature:

“It is thus clear that ‘one’ in this sense (when it means one qua individual) signifies only the isolation of the concrete individual in terms of its essence and quiddity, not the isolation of something extrinsic to its essence.”^[106]

Therefore, unity in the metaphysical sense is to be understood as the meaning that is synonymous to a thing’s essence. It is not to be considered as an accident of a thing’s essence as claimed by Avicenna.

5. Conclusion

5.1 Avicenna’s main innovations

In conclusion, the metaphysical work of Avicenna, The Metaphysics of the Healing, contains a number of original ideas that cast a new light on Aristotle’s metaphysics. Firstly, he applied Aristotle’s finite structure of science to the order of concepts (tasawwur), which allowed him to qualify notions as being, thing and unity as primary notions that are ‘impressed on the soul’. Secondly, he famously made a distinction between essence and existence, claiming that existence is a necessary concomitant of essence rather than a part of the essence’s definition. Thirdly, Avicenna applied the distinction between essence and existence as a ‘pattern of investigation’ to argue that unity, multiplicity, particularity and universality are all accidents to essence as well.

Averroes rebuts Avicenna on all these points. His main point of criticism is that Avicenna confused the understanding of the metaphysical concepts for their meaning in common language (the understanding of ‘the masses’). He understood ‘being’ as an accident of essence, while, correctly understood in the metaphysical sense, being is regarded as synonymous to essence. Similarly, Averroes criticized Avicenna for his confusion of the metaphysical ‘one’ with the numerical ‘one’, which led him to think that unity was an accident of essence, rather than synonymous to it.

5.2 On to the existence of God

The aim of this paper was to discuss the metaphysics of Avicenna that underlies his proof for the existence of God. With the abovementioned conclusions in hand, Avicenna proceeds to argue for God’s existence. As discussed in paragraph 2.6, abstracting essence from existence (and the other concomitants; unity, particularity, universality etc.) allows Avicenna to argue that essence is existentially neutral. There is nothing in it to tip the balance in favor of its existence rather than its nonexistence; its existence and non-existence are equally possible. This is not to say that, for example, Socrates might just as well not have existed, but that the essence of Socrates, humanity, does not necessitate existence. When Socrates exists, the attribute that he exists is an accident to his essence. Likewise, the essence horseness does not necessarily imply the existence of a certain horse, nor does animality. Their essences do not guarantee that they exist or that they do not exist. In other words, the existence of these things can be regarded as possible or contingent (mumkin al-wujūd bi-dhātih or simply mumkin).^[107]

These contingent beings are contrasted to the essences whose definition makes it impossible (mumtani^c) for the thing to exist. Take, for example, a square circle. A square circle, by its essence, cannot exist, because something cannot be a square and a circle at once. The essence of a square circle therefore guarantees that it cannot exist.

Having considered the possibility and impossibility of things, Avicenna argues that there must also be an existent that must necessarily exist (wājib al wujūd). This is because the contingent beings – who can equally exist or not exist – will always lead us to one question: Why, if we suppose that contingent beings exist, do they exist at all? In other words: if we suppose that we exist, why do we exist? That an essence which in itself does not guarantee existence exists, calls for explanation. An external cause is needed to explain why we, the contingent beings, have been specified with existence rather than non-existence. Hence we ultimately require our existence from one whose existence is not merely possible. This external cause must be an existent that is necessary, because otherwise the same requirement that is imposed on contingent beings is to be imposed on it, and so on ad infinitum.^[108] If the infinity of such causes is allowed, that would still not explain why the contingent beings exist. The chain must have a first cause, the existent necessary for itself, which is God. God has a unique nature: He is the only existent that is necessary by virtue of itself (min nafsih), whereas everything else that exists, exists by virtue of another (min ghayrih), i.e. by virtue of God. Therefore, Avicenna refers to God as the Necessary Existent who is the beginning of the existence of everything else.^[109]

Thus, Avicenna is arguing not merely that if the contingent beings exist, they must have an external cause, but also that this external cause itself is uncaused. Distinguishing essence from existence allows him to reason that the existence of contingent existents call for the existence of a first non-contingent cause. The uncaused cause is the existent that must exist in order for all the beings that are merely possible beings to exist. This uncaused cause is God, who through His act of creation adds existence to the essence of all other things.^[110]

Literature

Aersten, J. A. Medieval Philosophy as Transcendental Thought: From Philip the Chancellor (ca. 1225) to Francisco Suárez, Brill: Leiden-Boston 2012.

Al Gazālī, Logica (ed. C. H. Lohr), in: Traditio 21 (1965), pp. 239-288.

Aristotle, Metaphysics (transl. by W.D. Ross), available online at <http://classics.mit.edu/Aristotle/ metaphysics.html >.

Averroes, On Aristotle’s “Metaphysics”: An Annotated Translation of the So-called “Epitome” (transl. by R. Arnzen), De Gruyter: New York 2010.

Averroes, Tahāfut Al-Tahāfut (The Incoherence of the Incoherence) (transl. by S. van den Bergh), Oxford: Oxford University Press 1954.

Avicenna, The Metaphysics of The Healing (transl. by M.E. Marmura), Brigham Young University Press: Provo, Utah 2005.

Bertolacci, A. The reception of Aristotle’s Metaphysics in Avicenna’s Kitāb al-Sifā’: a milestone of Western metaphysical thought, Brill: Leiden-Boston 2006.

Menn, S. ‘Avicenna’s metaphysics’, in: P. Adamson, Interpreting Avicenna, Cambridge UP: Cambridge 2013, pp. 143-169.

Menn, S. ‘Fārābī in the Reception of Avicenna’s Metaphysics: Averroes against Avicenna on Being and Unity’, in: D. Hasse and A. Bertolacci (eds.), The Arabic, Hebrew and Latin Reception of Avicenna’s Metaphysics, Walter de Gruyter 2011, pp. 51-96.

Nájera, R. ‘Averroes’s Critique of Avicenna in the Epitome of Metaphysics’, Candidacy Paper, McGill University 2008, available online at <https://brown.academia.edu/RafaelNajera>.

1. 1. J. A. Aersten, Medieval Philosophy as Transcendental Thought: From Philip the Chancellor (ca. 1225) to Francisco Suárez, Brill: Leiden-Boston 2012. ↑

1. 1. A. Bertolacci, The reception of Aristotle’s Metaphysics in Avicenna’s Kitāb al-Sifā’: a milestone of Western metaphysical thought, Brill: Leiden-Boston 2006. ↑

1. 1. S. Menn, ‘Fārābī in the Reception of Avicenna’s Metaphysics: Averroes against Avicenna on Being and Unity’, in: D. Hasse and A. Bertolacci (eds.), The Arabic, Hebrew and Latin Reception of Avicenna’s Metaphysics, Walter de Gruyter 2011, pp. 51-96 and S. Menn, ‘Avicenna’s metaphysics’, in: P. Adamson, Interpreting Avicenna, Cambridge UP: Cambridge 2013, pp. 143-169. ↑

1. 1. Aristotle, Metaphysics (transl. by W.D. Ross), IV.1. ↑

1. 1. Aristotle, Metaphysics, I.2. ↑

1. 1. Aristotle, Metaphysics, IV.2. ↑

1. 1. Ibid. ↑

1. 1. Ibid.: “As, then, there is one science which deals with all healthy things, the same applies in the other cases also. (…) It is clear then that it is the work of one science also to study the things that are, qua being.” ↑

1. 1. Ibid. ↑

1. 1. Ibid.: “Hence to investigate all the species of being qua being is the work of a science which is generically one, and to investigate the several species is the work of the specific parts of the science.” ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 56. ↑

1. 1. Avicenna, The Metaphysics of The Healing (transl. by M.E. Marmura), Brigham Young University Press: Provo, Utah 2005, I.1, 2. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.1, 11. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.1, 13-18. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.2, 12, 17-18. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.2, 12. ↑

1. 1. Aristotle, Metaphysics, IV.1. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.2, 13. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 1. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 5. ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 82-86. ↑

1. 1. Al Gazālī, Logica, 1 (ed. Lohr), p. 239; J. A. Aersten, Medieval Philosophy as Transcendental Thought, p. 82-83. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 2. ↑

1. 1. Aristotle, Posterior Analytics, I.3; J. A. Aersten, Medieval Philosophy as Transcendental Thought, p. 83. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 4. ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 86. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 9. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 10. ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 87. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 8: “The meaning of ‘existence’ and the meaning of ‘thing’ are conceived in the soul and are two meanings (…)”. ↑

1. 1. Example from: S. Menn, Avicenna’s metaphysics, p. 150. ↑

1. 1. Marmura, p. 386, note 5. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 19. ↑

1. 1. This can also be inferred from the following passage in Avicenna, The Metaphysics of The Healing, I.5, 21: “The first thing to which it [the existent] belongs is the quiddity, which is substance, and then to what comes after it.” ↑

1. 1. Avicenna discusses the mu^ctazilite views on being and thing at The Metaphysics of The Healing I.5, 12-20 and 25-27. ↑

1. 1. Among others chapter 2, verse 117. ↑

1. 1. S. Menn, Avicenna’s metaphysics, p. 151. ↑

1. 1. S. Menn, Avicenna’s metaphysics, p. 152. ↑

1. 1. Ibid. ↑

1. 1. Roughly speaking, a primary intelligible is something that is realized in the mind out of a real, perceptible thing and that is a sort of paradigm of it. A primary intelligible thus implies counterparts in and outside the mind. Secondary intelligibles are also realized in the mind but only exist concomitantly with primary intelligibles after the latter are realized. They do not have counterparts in reality outside the soul. See R. Nájera, ‘Averroes’s Critique of Avicenna in the Epitome of Metaphysics’, Candidacy Paper, McGill University 2008, available online at <https://brown.academia.edu/RafaelNajera>, p. 20. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 12-13. ↑

1. 1. S. Menn, Avicenna’s metaphysics, p. 153. ↑

1. 1. Ibid. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, IX.4, 2. ↑

1. 1. Avicenna, The Metaphysics of The Healing, IX.4, 4. ↑

1. 1. See below, Avicenna, The Metaphysics of The Healing, III.3, 10 and 15. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 1. ↑

1. 1. Aristotle, Metaphysics, IV.2. ↑

1. 1. Aristotle, Metaphysics, X.1; J. A. Aersten, Medieval Philosophy as Transcendental Thought, p. 62. ↑

1. 1. Aristotle, Metaphysics, IV.2. ↑

1. 1. Ibid. ↑

1. 1. Ibid.: “in view of all these facts, the contraries of the concepts we named above, the other and the dissimilar and the unequal, and everything else which is derived either from these or from plurality and unity, must fall within the province of the science above named. And contrariety is one of these concepts; for contrariety is a kind of difference, and difference is a kind of otherness. Therefore, since there are many senses in which a thing is said to be one, these terms also will have many senses, but yet it belongs to one science to know them all”. ↑

1. 1. Aristotle, Metaphysics, X.2: “Evidently, then, unity in the strictest sense, if we define it according to the meaning of the word, is a measure, and most properly of quantity, and secondly of quality. And some things will be one if they are indivisible in quantity, and others if they are indivisible in quality; and so that which is one is indivisible, either absolutely or qua one.” ↑

1. 1. Aristotle, Metaphysics, X.2: “If, then, no universal can be a substance, as has been said our discussion of substance and being, and if being itself cannot be a substance in the sense of a one apart from the many (for it is common to the many), but is only a predicate, clearly unity also cannot be a substance; for being and unity are the most universal of all predicates. Therefore, on the one hand, genera are not certain entities and substances separable from other things; and on the other hand the one cannot be a genus, for the same reasons for which being and substance cannot be genera.” ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 5. ↑

1. 1. Avicenna, The Metaphysics of The Healing, III.3, 4. ↑

1. 1. Avicenna, The Metaphysics of The Healing, III.2, 20: “The one may correspond with the existent in that the one, like the existent, is said of each one of the categories.” ↑

1. 1. J. A. Aersten, Medieval Philosophy as Transcendental Thought, p. 91. ↑

1. 1. Avicenna, The Metaphysics of The Healing, III.2, 20. ↑

1. 1. Avicenna, The Metaphysics of The Healing, VII.1, 1; J. A. Aersten, Medieval Philosophy as Transcendental Thought, p. 91. ↑

1. 1. Avicenna, The Metaphysics of The Healing, III.2, 20: “They agree in that neither of them designates the substance of any one thing.” ↑

1. 1. Avicenna, The Metaphysics of The Healing, III.3, 10 and 15. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 1. ↑

1. 1. S. Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 53. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 4. ↑

1. 1. A. Bertolacci, The reception of Aristotle’s Metaphysics in Avicenna’s Kitāb al-Sifā’, p. 279. ↑

1. 1. S. Menn, Avicenna’s metaphysics, p. 157. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 5. I have used the same translation here as in S. Menn, Avicenna’s metaphysics, p. 157-158. Menn detects, in my view correctly, a mistake in Marmura’s translation of this passage, see p. 157, nt. 29. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 9. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 9 and 14. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 21. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 23: “(…) animal when looked up inasmuch as it is animal is neither particular nor nonparticular (…). On the contrary, both [alternatives] are denied it because, from the direction of its animality, it is only animal.” ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 26. ↑

1. 1. Ibid. ↑

1. 1. Ibid. ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 80. ↑

1. 1. Avicenna explicitly opposes this statement: “You have glimpsed in the natural sciences that God is neither a body nor the power of a body, but that He is one – free in every respect from matter and from admixture with motion. Hence, the inquiry concerning Him must belong to this science.” See The Metaphysics of The Healing, I.1, 12. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”: An Annotated Translation of the So-called “Epitome” (transl. by R. Arnzen), De Gruyter: New York 2010, p. 23-24. ↑

1. 1. Ibid., p. 24. ↑

1. 1. Aersten, Medieval Philosophy as Transcendental Thought, p. 80. ↑

1. 1. Avicenna, The Metaphysics of The Healing, I.5, 19. See paragraph 2.4. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 27: “Accordingly, the term ‘being’ can be reduced to precisely the following two meanings: that which is true, and that which exists outside the soul”. ↑

1. 1. Ibid., p. 28. ↑

1. 1. The actual grammatical problem is much more elaborate and complex; see Averroes, Tahāfut Al-Tahāfut (The Incoherence of the Incoherence) (transl. by S. van den Bergh), Oxford: Oxford University Press 1954, p. 223-224 and Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 58. ↑

1. 1. Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 73. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 29. ↑

1. 1. R. Nájera, Averroes’s Critique of Avicenna in the Epitome of Metaphysics, p. 21. ↑

1. 1. Ibid. ↑

1. 1. Ibid. Nájera here refers to Aristotle, Metaphysics, B.3. In Tahāfut al Tahāfut (in Discussion 7), Averroes points out that this (option 1b) is the position that Avicenna holds. See also Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 74. ↑

1. 1. Nájera, Averroes’s Critique of Avicenna in the Epitome of Metaphysics, p. 22. ↑

1. 1. Averroes, Tahāfut Al-Tahāfut, p. 179. ↑

1. 1. Averroes, Tahāfut Al-Tahāfut, p. 180. ↑

1. 1. Averroes, Tahāfut Al-Tahāfut, p. 224; Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 58. ↑

1. 1. Avicenna, The Metaphysics of The Healing, V.1, 4. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 35. ↑

1. 1. Ibid., p. 35-36; Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 76. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 36. ↑

1. 1. Aertsen calls it “the mathematical one”; Aersten, Medieval Philosophy as Transcendental Thought, p. 93. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 38; Menn, Fārābī in the Reception of Avicenna’s Metaphysics, p. 77. ↑

1. 1. Averroes, On Aristotle’s “Metaphysics”, p. 38. ↑

1. 1. Ibid. ↑

1. 1. Avicenna, The Metaphysics of The Healing, VI.1, 12. ↑

1. 1. Avicenna, The Metaphysics of The Healing, VIII.1, 4. ↑

1. 1. Avicenna, The Metaphysics of The Healing, VIII.1, 2. ↑

1. Avicenna, The Metaphysics of The Healing, VIII.3, 6. ↑