AVICENNA iv. Metaphysics

a philosopher whose metaphysical system is one of the most comprehensive and detailed in the history of philosophy.



iv. Metaphysics

General characteristics. Avicenna’s metaphysical system is one of the most comprehensive and detailed in the history of philosophy. Its ingredients, its conceptual building blocks, so to speak, are largely Aristotelian and Neoplatonic, but the final structure is other than the sum of its parts. Avicenna himself hints at this when in introducing his magnum opus, the voluminous Šefāʾ (Healing), he writes: “There is nothing in the books of the ancients but we have included in this our book. If something is not found in a place where it is normally found, it would be found in another place where I judge it more fit to be in. I have added to this what I have apprehended with my thought and attained through my reflection, particularly in physics, metaphysics and logic” (Šefāʾ, Isagoge, pp. 9-10).

While the ingredients of his metaphysics derive “from the books of the ancients,” Avicenna criticizes, selects and refines this material, but above all, informs it with his own insights to construct a world-view that has a character all its own. He also injects into it a pattern of deductive reasoning that anticipates the kind of thinking encountered in seventeenth-century European rationalist philosophies. At the same time, it should be remembered that his metaphysics is part of medieval Islam’s intellectual history. It represents a climactic development of medieval Islamic Aristotelian and Neoplatonic thought. It also has to be understood (in part, at least) as a response to doctrines encountered in Islamic theology (kalām).

The Islamic philosopher who influenced Avicenna most was Fārābī (d. 339/950). Avicenna was indebted to Fārābī’s various exegeses of Aristotle’s works, logical and philosophical. He was also greatly influenced by the Neoplatonic emanative scheme Fārābī outlines in some of his more popular works. Avicenna, however, introduces important modifications to this scheme, gives a more comprehensive and detailed account of the descent of beings from God, and makes the connection between his version of emanation and the essence-existence distinction explicit and intimate. Thus the two schemes while closely related remain distinct. It should also be added that Avicenna’s theory of the state, which is connected with his metaphysics, is grounded in Fārābī’s political philosophy. There is, moreover, in Avicenna’s metaphysics an underlying Farabian motif, namely, that the quest after philosophical knowledge is for the sake of perfecting one’s soul and hence for the attainment of happiness in this world and the next.

As to the Islamic theologians, the motakallemūn, his criticism of their doctrines tends to be muted. Nonetheless, it represents an important undercurrent of his metaphysical writings. He refers to the theologians by name when criticizing their interpretation of the meaning of the term “origination,” ḥodūṯ, and the doctrine of the world’s creation ex nihilo it implies. In other instances, however, he makes no explicit mention of the motakallemūn, but the doctrines he criticizes are definitely identifiable as held by one of their schools. Thus, for example, he criticizes the doctrine of latency (komūn), a theory that has Stoic antecedents, but which in Islam was developed by the Muʿtazilite theologian Ebrāhīm Naẓẓām (d. ca. 840) and identified with him and his followers. Avicenna is also highly critical of the notorious Muʿtazilite argument for bodily resurrection and the doctrine on which it is based, namely that nonexistence (ʿadam) is “a thing” (šayʾ). Again, in his discussions of efficient causality, he answers typical arguments used by the Asḥʿarite occasionalist theologians to deny secondary causes. It should be added that as an Aristotelian, Avicenna criticizes and rejects atomism, his criticism, no doubt, being directed at the Greek atomists. But was it not aimed at kalām atomism as well? Here, again, there is no reference to the motakallemūn, the vast majority of whom were atomists. It is true that their doctrine of the transient atom, temporally created ex nihilo, contrasts sharply with the Greek concept of eternal atoms. But Avicenna’s criticism is logically applicable to both versions of atomism. Taking into account that he opposed a number of the doctrines of the motakallemūn, including that of the world’s creation ex nihilo, intimately related to their atomism, it seems unlikely that he did not intend his criticism of atomism to include its kalām version.

Criticism in Avicenna’s metaphysical writings, by no means confined to the kalām or to atomism, is a manifestation of a very characteristic aspect of these writings, the analytic. It is here that one encounters his distinctions, clarifications and hard-headed attempts to solve problems. This is complemented by a synthetic aspect, where he strives to construct a deductive system. Both aspects, however, interweave, the system he constructs being constantly buttressed by the analyses and distinctions he makes. This system is admittedly an ambitious one, particularly as it includes a cosmological scheme in which he endeavors to infer from the First Principle, God, the Ptolemaic astronomical scheme to which he subscribes. Such an attempt, wide open as it is to serious criticism, serves to reveal a facet of his rationalist approach, namely, his belief that in principle, at least, some human minds, whether intuitively or “naturally,” as with prophets, or through arduous processes of discursive reasoning, are capable of grasping the basic structure of reality as it emanates from its Source.

This brings us to the “rationalist” character of Avicenna’s philosophy, manifest in what he holds to be (a) the object of our knowledge and (b) the manner of attaining it. The principle of all existence, God, for Avicenna, is pure intellect (ʿaql maḥż) and hence the highest object of human knowledge is intellect. All other existents, whether minds, souls or bodies, emanate from the pure intellect, God. They form an orderly hierarchical chain of causes and effects that are necessarily connected and hence (when all necessary conditions obtain) are rationally inferable from each other. Knowledge by its very definition is conceptual, intellectual, consisting (on the human level) of the mind’s reception of the intelligibles (maʿqūlāt). One class of these intelligibles which includes the self-evident truths of logic are received directly by all men from the Active Intellect, the last of the celestial intelligences emanating from God. They are received “directly” in the sense that this reception requires neither observation of the external world nor the thinking processes associated with such observation. Another class of intelligibles, less simple and less general, the secondary, consisting of universal concepts and inferences, are normally “acquired” in a different manner. Normally, they require the presence of the self-evident logical truths and observation of the external world with concomitant thinking activities on the sensory, imaginative, particular levels. Observation and its accompanying thinking activities, however, do not themselves in the real sense acquire the secondary intelligibles. Rather, they are activities that prepare the soul for the reception of the secondary intelligibles from the Active Intellect. Only prophets can receive the secondary intelligibles directly, without the need of the preparatory activities of the soul and the learning processes that accompany them. Thus the object of knowledge is the intelligible, received from a rational principle, the Active Intellect.

But this is not all. To fully appreciate the extent of Avicenna’s rationalism it should be noted that he also includes with the class of intelligibles that normally do not require for their reception perception of the external world primary concepts that are the most general—the concepts of “the existent,” ”the thing,” and “the necessary.” These, like the self evident propositional truths of logic, are “impressed on the soul in a primary manner.” This class of intelligibles, consisting of the primary concepts and the self-evident truths of logic, are sufficient in Avicenna’s system for formulating a proof leading to the existence of God, demonstrating His uniqueness, and for inferring the existing of the world (with its order) from God. Thus the highest form of metaphysical knowledge is attainable rationally, independently of our perception of the external world.

The affinity of this rationalism to seventeenth-century continental European modes of philosophizing has often been noted, particularly the similarity between the Cartesian Cogito and Avicenna’s hypothetical example of a human floating in space (cf. Psychology). According to this example, if we imagine ourselves to be born all at once, fully mature, but suspended in space in such a manner that we are totally unaware of our physical and bodily circumstances, we would still be aware of ourselves as individual selves. Without denying parallels between this example and aspects of Descartes’ process of systematic doubting of the senses, it is important to recognize a difference quite fundamental for understanding Avicenna’s metaphysical approach.

Avicenna’s metaphysical starting point is not doubt. (The primary intention of the example of a person suspended in space is to show that the human rational soul is immaterial and individual.) As has been noted, the concept of “the existent” for him is a primary concept, intuited immediately. It is indubitable. He begins one version of his proof from contingency for God’s existence with the statement: “There is no doubt that there is existence” (lā šakka anna hāhonā wojūdan). But existence, as he points out, divides into that which is in itself necessary and that which in itself is only possible. The existents immediately encountered (including ourselves) are in themselves only possible. They can exist or not exist. Yet in fact they do exist. Why is this the case? In his metaphysics, Avicenna, in effect, seeks an answer to this very question, namely, why is it that that which in itself is only possible (and this includes the whole world as distinct from God) exists at all?

Definition and scope of metaphysics. Although the question of why is it that that which in itself is only possible exists at all is at the heart of Avicenna’s metaphysics, it does not constitute its starting point. In the Metaphysics of the Šefāʾ, for example, it suggests itself quite unobtrusively when Avicenna is establishing one of his basic premises for his proof of God’s existence. Nor is the existence of God and the simplicity of His essence “the subject matter” of metaphysics. Rather, as will be shortly seen, these are among the things “sought after” in metaphysics. Avicenna’s starting point and conception of metaphysics are Aristotelian. This Aristotelianism is clearly seen in the distinction he draws between metaphysics and the two other theoretical sciences, physics and mathematics. He makes this distinction in terms of two related criteria: (a) the relation of the objects of knowledge belonging to each of these sciences to matter and motion; (b) the subject matter, in its broadest sense, of each of these disciplines.

The objects of knowledge of both physics and mathematics are always “mixed” with matter (and motion), but in different ways. With physics, the object is always “mixed” with a specific kind of matter. A human being, for example, as the object of natural science, can not be separated from a specific kind of matter, from the material body of the genus, animal. Again, the object may be of a different sort that can be separated from matter—causality, for example. But when it is the object of natural science, it must be associated, not only with matter, but with matter of a specific kind. The physicist is concerned with the cause of motion of this or that specific kind of matter, not with causality as such. In the case of mathematics, on the other hand, although its object is always “mixed” with matter, it is not “mixed” with a specific kind of matter. Triangles and squares in external non-mental existence must be of some kind of material, but not confined to a specific kind. As such, as objects of knowledge, they undergo a degree of abstraction, whereby the mathematician can consider them dissociated from a specific kind of matter. Other objects of mathematical knowledge, such as plurality or unity, can be separated from matter. But as objects of mathematical inquiry, they are treated as associated with matter, but not of a specific kind. Again, there is a degree of abstraction. But they are not regarded in pure abstraction. The mathematician considers them in terms of quantity, related to some kind of matter or another, but not confined to a specific kind.

Metaphysics, however, always has as its object that which is not “mixed” with matter. The object may be necessarily immaterial, as with God and mind. It can, however, consist of objects that can mix with matter. The metaphysician, however, is concerned with these objects in themselves, men ḥayṯo hīa hīa, abstractly and immaterially. Thus to take causality again as an example, unlike the natural scientist who is concerned with the cause of a specific kind of matter, the metaphysician is concerned with causality as such and with causality as one of the concomitants of the existent considered as such. This brings us to the second criterion for the distinction between the three theoretical sciences: their respective subject matter.

All three theoretical sciences have for their subject matter the existent, but with a difference. Physics is concerned with the existent inasmuch as it is in motion or in its relation to motion. Mathematics is concerned with the existent inasmuch as it is quantified or relates to measure and quantity. Metaphysics, on the other hand, has for its object the existent without qualification. Its subject matter is the existent inasmuch as it exists (al-mawjūd be mā howa mawjūd), or, as Avicenna puts it in his Najāt, “absolute existence” (al-wojūd al-moṭlaq). Metaphysics undertakes investigating the relation of the existent to the ten categories, the states that affect it, and the concomitants (lawāḥeq) that adhere to it. Following the methodology of the Posterior Analytics, Avicenna distinguishes between “the subject matter” (mawżūʿ) of metaphysics and that which “is sought in it” (maṭlūb). Among the things that are sought after and established in metaphysics are the principles presupposed in natural science and mathematics. In this sense, physics and mathematics receive “their credentials,” as it were, from metaphysics.

Among the things “sought after” in metaphysics are the four causes (material, formal, efficient, and final) of existing things and the ultimate cause of all existence, God. Hence, investigating the four causes and the existence and nature of God do not constitute “the subject matter” of metaphysics. This, as has been pointed out, is the existent inasmuch as it exists. But the concept of the existent qua existent as the subject matter of metaphysics raises a methodological difficulty regarding the quest in it for the principles of existing things. “If the existent is made the subject of this science,” it could be argued, writes Avicenna, “then the principles of the existent can not be established in it, since in every science, investigation is of things concomitant to its subject, not of its principles” (Šefāʾ, Metaphysics, p. 14).

In the endeavor to resolve this problem, Avicenna maintains that “theoretical inquiry of the principles is also an investigation of the concurrent concomitants (ʿawāreż) of this subject.” For, being a principle is not a defining characteristic of “the existent.” He then adds a qualification: The principle sought after is not the principle “of the whole of existence.” Otherwise the principle would be a principle of itself. The principle that is sought after is hence the principle of the existent that is caused. God, to paraphrase Avicenna, can not be the principle of His own existence, but is the principle and cause of all other existents.

This brings us to the ultimate quest, ultimate principle sought after in metaphysics, the existence of God. This existence, Avicenna asserts, is not self-evident, but has to be demonstrated. Furthermore, its demonstration belongs solely to metaphysics, not to any other theoretical science. Assertions relating to God’s existence in the Physics of the Šefāʾ, he states, were out of their place, put there only to whet the reader’s appetite. As indicated earlier, Avicenna offers not only a rational proof for God’s existence, but also a rational deduction from this existence of the world’s existence and order. Proof and deduction, however, employ the distinction between essence and existence, for which Avicenna is noted. This distinction underlies his very significant theory of universals, as well as his theory of efficient causality. For this reason, before turning to the proof of God’s existence, it is perhaps best to begin with this distinction as it relates to his theory of universals and also say something supplementary about his theory of efficient causality.

The essence-existence distinction. For Avicenna, the distinction between essence and existence applies to all existents, actual and potential, other than God. At the heart of this distinction is the theory of the essence, quiddity, or nature of such existents considered strictly in itself. An essence, Avicenna states, may exist in external reality, associated with circumstances peculiar to that reality. These circumstances associate with it to form a particular existent. The essence may also exist as a concept in the mind where in this mental existence it also is associated with circumstances peculiar to this existence—for example, circumstances that render it a subject or a predicate. But, he maintains, there is also “a consideration of the essence inasmuch as it is that essence, without being related to the two [kinds of] existence” (Šefāʾ, Isagoge, p. 15). In itself, or as such, the essence does not include the idea of existence, whether this is external or mental existence. Existence is not a defining characteristic of essences. From what a thing is, it can not be inferred that it exists.

According to Avicenna, the quiddity (or essence) considered simply as a quiddity, excludes not only the idea of existence, but also the concomitants of existence, unity and plurality. Thus in his typical example of “horseness” as a quiddity considered in itself, he states that “it is neither one nor many, exists neither externally nor in the soul.” Moreover, he maintains, the quiddity considered in itself excludes the ideas of universality and particularity. In short, the quiddity as such excludes the ideas of existence, unity, plurality, particularity, and universality.

Avicenna uses this concept of the quiddity considered in itself and the distinction between essence and existence that it carries with it to resolve two problems pertaining to universals. The first is a logical problem that has to do with the predication of a quiddity of a subject. If the quiddity as such included universality and particularity, the results would be odd indeed. For then universality or particularity (but not both, since they are mutually exclusive) would form part of the very definition of the quiddity. To use his example, if animality includes universality in its very definition, then we can not predicate it of a particular animal. If, on the other hand, particularity is included in the definition of animality, then this would not merely exclude its predication of a universal subject, but of any individual other than the one specified in the quiddity’s definition.

The answer Avicenna finds is in the concept of a quiddity which, when considered in itself, is devoid of the notions of universality and particularity. Universality and particularity are then added to it when it is conceived in the mind. This brings us to Avicenna’s important theory of the universal, which for him is always a concept in the mind. The quiddity as such is not a universal. It is, however, a component of the universal. For the universal is compounded of two things, the quiddity as such and universality, that quality that renders the quiddity predicable of many instances. The general framework of this theory is Aristotelian. But Avicenna introduces refinements and the distinction between the quiddity as such and universality. He also adds to it a Neoplatonic dimension by maintaining that quiddities have existence in the celestial intelligences, as well as in the particulars of sense and in the human minds.

The second problem relating to universals which Avicenna strove to resolve is metaphysical. This is the problem of the one and the many, in an Avicennian context. How can the selfsame quiddity be “found in many,” to use his own words, and not be many? To answer this, Avicenna again invokes the concept of the quiddity considered as such. For although a quiddity can exist in external reality associated with particular circumstances, rendering it in this association an individual, it can be considered in itself, for what it is, in dissociation from these circumstances. When thus considered, it excludes the ideas of unity and plurality: These become totally inapplicable to it. Thus if one asks whether a quiddity like humanity is one or many, Avicenna’s reaction to such a question is that “there is no need for a reply because inasmuch as it is the defining identity (howīya) of humanity it is other than the two alternatives. In the definition of that thing, there is nothing except humanity alone” (Šefāʾ, Metaphysics, pp. 197-98).

If, then, existence (and its concomitants) are extraneous to the quiddity as such, the quiddity is existentially neutral, so to speak. 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. That a quiddity which in itself is only possible in fact exists calls for explanation. The explanation that Avicenna offers includes his establishing a premise necessary for his proof of God’s existence. This is the premise that the existent that in itself is only possible is causally necessitated by another existent. The argument to establish this premise, as will be shortly seen, is a metaphysical argument. It is, however, complemented by an epistemological argument (which was later adopted by Latin scholastics) that should be noted. This is the argument from the observation of regularities in nature. Avicenna is only too well aware that such observation alone is insufficient to establish the principle of necessary causal connection. Such observation, he asserts, leads only to concomitance. Something else is needed. This is hidden premise (qīās ḵafīy) to the effect that if the regularities were accidental or coincidental they would not have happened always or for the most part (cf. Aristotle, Physics 2.5.156b.10-16). From this he concludes that these regularities are the necessary outcome of inherent essential casual properties in things. It should be added that Avicenna subscribes to the four Aristotelian causes. Unlike Aristotle, however, he does not confine efficient causality to the production of motion, but maintains that, as with God in producing the world, it is productive of existence itself.

God’s existence and the world’s emanation. Demonstrating God’s existence, His utter oneness and the manner of the world’s emanation from Him are the high points of Avicenna’s metaphysical endeavor. The proof he offers is his proof from contingency, noted for its a priori character, that is, for its total dependence on reason. Thus, he does not argue for the contingency of things on the basis of our observation of change in the world. For the concept of the possible is either a primary concept, immediately intuited by the mind, or rationally derived from a primary concept, immediately intuited by the mind, the concept of the necessary. It is also a metaphysical proof, as distinct from a proof in Physics. Thus it is not based on the observation of motion in the world, leading ultimately to the Prime Mover. It is not in any sense a proof that infers God’s existence from the observation of His handiwork. On this Avicenna is explicit. After giving one version of his proof from contingency, for example, he writes: “Reflect on how our proof for the existence and oneness of the First and His being free from attributes did not require reflection on anything except his existence itself and how it did not require any consideration of His creation and acting, even though the latter [provide] evidential proof (dalīl) for Him. This mode, however, is more reliable and noble, that is, where when we consider the state of existence, we find that existence inasmuch as it is existence bears witness to Him, while He thereafter bears witness to all that comes after Him in existence” (Ešārāt, p. 482).

Although Avicenna gives closely related but somewhat different versions of the proof, they all share its a priori character. Underlying these versions is Avicenna’s theory that there are primary concepts, those of “the existent,” “the thing,” and “the necessary,” that are rationally intuited without the need for perceptual experience of the external world. These parallel the self-evident propositional logical truths that, again, are purely rational. The versions of the proof also share basically the same structure. An existent in itself is either necessary or only possible. If necessary, then this is the existent we are seeking, God. If only possible, then it can be demonstrated that such a contingent being ultimately requires the existent that is necessary in Himself. In either case, there must be an existent necessary in Himself, the one God.

The version of the proof in the Metaphysics of the Šefāʾ, although it is dispersed in different places in this work and has to be reassembled, remains the most detailed and comprehensive. It is also the one that argues explicitly for the causal premise presupposed in the other versions. The proof in this version can be summed up as follows. Existents are either such that their existence is in itself necessary or only possible. If we suppose an existent that in itself is necessary, then, it can be shown that it would not be caused, would necessarily be one, unique and without multiplicity in its being. If we suppose an existent that in itself is only possible, then it can be shown that it would require for its existence the existent that is necessary in Himself. For an existent that in itself is only possible can equally exist or not exist. Why, then, if we suppose it to exist, should it exist at all? An external cause would be needed to explain why it had been “specified” with existence rather than non-existence. Now if in relation to the supposed cause, the existence of the contingent is not “necessitated,” then it would remain purely possible and no explanation for its existence would have been given. Another cause would have to be posited and if this is not a necessitating cause, yet another, and so on ad infinitum. Even if, for the sake of argument, the infinity of such causes is allowed, they would still not explain why the contingent exists. Hence, since we have supposed it to exist, then the extraneous cause would have to necessitate it. In other words, Avicenna is arguing not merely that if the contingent exists, it must have an extraneous cause, but that this extraneous cause necessitates its existence. Thus the existence of such a contingent, while in itself only possible, would be necessary through another.

The cause that necessitates its effect, for Avicenna, is the essential cause. It is the accidental cause that precedes its effect in time and as such a chain of accidental causes and effects can be infinite. A chain of such accidental causes would not constitute an actual infinite. Not so with the chain of essential causes and their effects. The essential cause coexists with its effect, its priority to the effect being ontological not temporal. A series of coexisting causes and effects can not be infinite. For the infinite they would constitute would be an actual infinite, which, for Avicenna, is demonstrably impossible. The chain must have a first cause, the existent necessary for Himself, God.

That Avicenna also wishes to “infer” the existence of the world and its order (though not in all its detail) from God’s existence, in the way in demonstration the effect is inferred from the cause, is clear from the following statement of intention early in the Metaphysics of the Šefāʾ: “It will become clear to you anon through an intimation that we have a way of proving the First Principle, not by the method of evidential inference (estedlāl) from the things perceived by the senses, but by way of universal rational premises that render it necessary that there is for existence a principle that is necessary in its existence, that makes it impossible for this principle to be in any way multiple, and makes it necessary that the whole is necessitated by Him according to the order possessed by the whole. Because of our incapacity, however, we are unable to adopt this demonstrative method which is the method of arriving at the secondary existents from the primary principles and the effect from the cause, except with some groupings of the ranks of existing things, not in detail” (Šefāʾ, Metaphysics, p. 21 ).

There can be little doubt that the “groupings of the ranks of existing things” in the last sentence above refers to the celestial triads which, according to Avicenna, emanate from the first intelligence that proceeds directly from God. In explaining this emanative scheme, he employs the concepts of the necessary in itself, the necessary through another, and the possible in itself, the latter two being the consequence of his essence-existence distinction.

God, according to Avicenna, undergoes an eternal act of self-knowledge, resulting in a necessitated effect, a first intelligence. Involved here is the principle that from the one only one proceeds. The first intelligence then encounters the three facts of existence: (1) God’s being necessary in Himself; (2) its own existence as necessitated; (3) its own existence as in itself only possible. It conceives each of these facts of existence. Since from the one only one proceeds, each of these three acts of cognition produce one existent—hence the triads. Its act of knowing (1) produces another intelligence; of knowing (2) a celestial soul; of (3) a celestial body, the outermost sphere of the universe. The second intelligence undertakes a similar cognitive process resulting in the emanation from it of the sphere of the fixed stars. This cognitive activity is repeated by successive intelligences, giving rise to successive triads. The bodily components of these triads include the planetary spheres and the spheres of the sun and the moon. The last of the celestial intelligences is the Active Intellect, from which our world of generation and corruption emanates. In each of the celestial triads, the intellect acts as the teleological cause of that triad: The soul within the triad desires the intellect, causing the eternal circular motion of the third component of the triad, the celestial sphere. It should be added that the emanative process is eternal. God, the eternal necessitating cause, ever in act, necessitates the existence of an eternal effect, the world.

Divine knowledge, providence, and prophethood. The world thus emanates from God as a consequence of His self-knowledge. This self-knowledge entails His knowing Himself as the cause of all existents, and hence knowing the consequent effects of His causality. Avicenna states that in this way God knows all particular existents, but “in a universal way.” This type of knowing the particular also belongs to the celestial intelligences, as distinct from the celestial souls that know particulars in their particularity. To understand what knowing the particular “in a universal way” means, one must consider a peculiarity of the Avicennian celestial triads.

This peculiarity, a consequence of the principle that from the one only one proceeds, consists in the fact that in this system each existent in each of the celestial triads is the only member of its species. This is in total contrast with the existents in the terrestrial world, where a triad of existents may be said to continue. But this would be a triad of kinds only, not of individuals each of which is the sole member of its species. Thus there are numerous human intellects of a species, numerous souls and numerous bodies of various species. Now Avicenna holds that divine knowledge is conceptual, eternal, and changeless. Its object is the universal. In the case of the celestial triads, God knows the species of each individual of the triad and, moreover, that each individual is the only member of that species. In this sense, knowing the universal species means knowing the one member of this species. This applies also to celestial events like eclipses whose occurrences are mapped out eternally for God, so to speak, without this involving any change in Him. This is also possible because the event is related to individuals that are the only members of their species. When it comes to the terrestrial world, where the individual is not the only member of its species, God (and the celestial intelligences) knows only the kinds of existents, not their individual members. Of the celestial beings, only the souls in the triads know the particulars of the terrestrial world as particulars. These souls are instrumental in causing particular temporal events in the terrestrial world. Not only do they know the particulars in this world as particulars, but have fore-knowledge of future terrestrial temporal events.

Closely associated with Avicenna’s doctrine of divine knowledge is his doctrine of divine providence. He writes: “Providence consists in the First’s knowing in Himself [the mode] of the good order, in His being in Himself a cause of goodness and perfection in terms of what is possible, and in His being satisfied with [its having the order] in the manner that has been mentioned. He would then conceive the good order in the best possible manner. Consequently, what He conceives in the best possible manner would emanate from Him in the manner—in terms of what is possible—that is most completely conducive to order” (Šefāʾ, Metaphysics, p. 415).

This is not to deny the existence of evil which enters the world of generation and corruption, associated with terrestrial matter and potency. In a detailed analysis of the different types of mundane evils, moral and physical, Avicenna maintains that they affect individuals, not the species and that, although numerous, they are not predominant. Most evils are accidental consequences of what produces the greater good. Fire, for example, is basically beneficial, but on occasion harms individuals. Could not God then have created the world free from such harm, such evil? Not this type of world, Avicenna answers, since then, to take the example of fire, he would have to create a fire that neither warms nor burns, a contradiction. A world free from evil is possible in a different mode of existence. But the creation of such a world would exclude the creation of ours which, though not without evils, would have greater good than the former. For Avicenna, this is the best of all possible worlds.

Politicalphilosophy. The concept of divine providence relates Avicenna’s metaphysics to his political philosophy. This political philosophy, essentially Farabian, rests on the theory of prophethood and revelation. The law, revealed through prophets, is not only necessary for the existence of human society, but for the very survival of man. It consists of the truths of theoretical and practical philosophy, conveyed, however, in language which the vast, non-philosopher, majority of humanity can understand. This is the language of the particular example, instead of the abstract universal concept, of the image and the symbol. Without prophets and the law they reveal the good order will not be realized in the terrestrial world of men. The existence of the law-revealing prophet is the necessary consequence of God’s knowledge of the good order, an expression of His providence.

The appearance of prophets on the historical scene, however, is very infrequent. This has practical implications regarding the setting down of institutions and traditions to ensure the continuance of the good order once the prophet is gone. But the infrequency of the appearance of prophets has a metaphysical side, a metaphysical explanation involving Avicenna’s doctrine of the human soul. This soul, individual and immaterial, emanates from the celestial intelligences. It is created with the body, but not imprinted in it. Its association with the body is conditioned by the material compositions that receive it. These compositions vary and their variance determines the quality of the souls that are created with them. The bodily composition that induces the reception of a prophetic soul, which is the highest quality of human souls, occurs very infrequently, Avicenna tells us. This soul is endowed with exceptional cognitive powers. Some prophetic souls receive symbolic knowledge directly from the celestial souls. Others (of a still higher rank) receive from the Active Intellect all or most of the intelligibles instantaneously. These intelligibles are then conveyed in the language of imagery, example, and symbol understood by all.

In the hierarchy of existents, the prophet stands highest in the world of generation and corruption. In Avicenna’s cosmology he is, in effect, a link between the celestial and terrestrial worlds. It is perhaps no accident that Avicenna concludes the Metaphysics, which is the last part of the encyclopedic Šefāʾ, with the following words: “If one combines with justice speculative wisdom, he is the happy man. Whoever, in addition to this, wins the prophetic qualities becomes almost a human god. Worship of him, after worship of God, becomes almost allowed. He is indeed the world’s earthly master and God’s deputy in it.”



Works by Avicenna. The most comprehensive expression of Avicenna’s metaphysics is given in the Metaphysics of his Šefāʾ, complemented by other parts of this work. Critical editions of the Arabic text of the Šefāʾ by a team of scholars under the supervision of E. Madkūr have been appearing at Cairo since 1952.

Of these the most pertinent for Avicenna’s metaphysical thought include the following books: al-Madḵal (Isagoge), 1952; al-Maqūlāt (Categories), 1959; al-Borhān (Demonstration), 1955; al-Nafs (Psychology), 1975; Elāhīyāt (Metaphysics), 2 vols., 1960. Vol. I of G. C. Anawati’s French translation of the Elāhīyāt was published in Paris, 1979.

Among Avicenna’s numerous shorter Arabic works pertaining to metaphysics, special attention must be given to the following two books: (1) Ketāb al-ešārāt wa’l-tanbīhāt. This was edited by J. Forget, Leiden, 1882, and recently by S. Donyā, Cairo, 1958. Donyā’s edition includes the very important commentary on this work by Naṣīr-al-dīn Ṭūsī (d. 1274).

For a French translation of the Ešārāt, see Ibn Sīnā (Avicenne), Le livre des directions et remarques, tr. A. M. Goichon, Paris, 1955. (2) Ketāb al-najāt, Cairo, 1938.

For a translation of the part on the soul of this work, see F. Rahman, Avicenna’s Psychology, London, 1952, repr. Westport, Conn., 1981.

For an English translation of the Metaphysics of Avicenna’s most important work in Persian, his Dāneš-nāma-ye ʿalāʾī, see P. Morewedge, The Metaphysics of Avicenna (Ibn Sīnā), New York, 1973.

Studies. M.-T. d’Alverny, “Anniya-Anitas,” Mélanges offerts à Ētienne Gilson, Paris and Toronto, 1959.

M. Cruz Hernandes, La metafisica de Avicena, Granada, 1949.

L. Gardet, La pensée religieuse d’Avicenne (Ibn Sīnā), Paris, 1951.

A. M. Goichon, La distinction de l’essence et de l’existence d’après Ibn Sīnā (Avicenne), Paris, 1937.

G. F. Hourani, “Ibn Sīnā’s "Essay on the Secret of Destiny",” BSOAS 29, 1966, pp. 25-48; “Ibn Sīnā on Necessary and Possible Existence,” The Philosophical Forum 4/1, 1972, pp. 74-86.

M. E. Marmura, “Some Aspects of Avicenna’s Theory of God’s Knowledge of Particulars,” JAOS 82/3, 1962, pp. 299-312; “Avicenna’s Chapter on Universals in the Isagoge of his Shifāʾ,” in Islam, Past Influence and Present Challenge, ed. A. T. Welch and P. Cachia, Edinburgh, 1979, pp. 34-56; “Avicenna’s Proof from Contingency for God’s Existence in the Metaphysics of the Shifāʾ,” Mediaeval Studies 42, 1980, pp. 337-52; “Avicenna on the Division of the Sciences in the Isagoge of his Shifāʾ,” Journal of the History of Arabic Science 4, 1980, pp. 241-51.

P. Morewedge, “Philosophical Analysis and Ibn Sīnā’s "Essence-Existence" Distinction,” JAOS 92/3, 1972, pp. 425-35.

S. H. Nasr, Islamic Cosmological Doctrines, Cambridge, Mass., 1964.

J. Owens, “Common Nature: A Point of Comparison between Thomistic and Scotistic Metaphysics,” Mediaeval Studies 19, 1957, pp. 1-14.

F. Rahman, “Essence and Existence in Avicenna,” Mediaeval and Renaissance Studies 4, 1958.

Dj. Saliba, Ētude sur la métaphysique d’Avicenne, Paris, 1926.


iii. Logic

Avicenna’s works on logic. Many of Avicenna’s works on logic are extant and most of them have been published. With the exception of two Persian works, Dāneš-nāma-ye ʿalāʾī and Andar dāneš-e rag (see below, xi), all of his works are written in Arabic.

The nine parts that make up the first treatise of Ketāb al-šefāʿ (Book of the healing [of the soul]), Avicenna’s philosophical summa, are devoted to logical matters. The first of these parts, the Madḵal, is an introduction to the other eight, each of which corresponds to one of the Aristotelian logical works, collectively known as theOrganon or “instrument of science.” The Madḵal, on the other hand, corresponds to Porphyry’s Isagoge, a work that strongly influenced the writings of Islamic logicians as well as those of medieval Latin logicians. In addition to these works, the first part of Avicenna’s Ešārāt as well as the first part of the Najāt are summaries of Avicenna’s version of Aristotelian logic.

The last work that Avicenna wrote on the subject of logic, which like the Najāt and the Ešārāt is a summary of his logic, is called Manṭeq al-Mašreqīyīn. It is the only extant portion of a philosophical encyclopedia he reportedly wrote or meant to write.

Avicenna on the subject matter of logic. Avicenna’s works on logic usually begin with a discourse on the utility and the subject matter of logic. Logic for him is an instrument (āla) that has numerous functions. Thus in the Najāt (p. 3) which is an abridgement of the Šefāʾ, he writes: “I start with a detailed description of the art of logic because it is the instrument which prevents the mind from committing errors both in conception (taṣawwor) and in judgment (taṣdīq). It is the instrument that leads to true beliefs as well as to the reasons for and the right way to achieve them.” By the “right way” Avicenna is referring to the methods by which one can teach a proper definition, as well as to the mastering of the theory of the syllogism and other methods which guard the mind against committing errors in judgment, i.e., in composing propositions. Knowing how to define leads to conceptual soundness, whereas knowing the methods that lead from the known to the unknown guarantees that one makes sound judgments. That which leads to a clear and definite conception (taṣawwor mostaḥṣal is the expository statement (qawl šāreḥ) which can be either an essential definition (ḥadd) or a descriptive definition (rasm). That which leads to a definite judgment (taṣdīq yostaḥṣal) is an argument (ḥojja) which can be either a syllogism (qīās), an induction (esteqrāʾ), or an analogy (tamṯīl ) (Ešārāt, pp. 181-85; Manṭeq, p. 10). According to Avicenna the latter can help identify not only what is true and valid, but also what is false and invalid (Manṭeq, pp. 5-6). Moreover, these methods are a necessary condition not only for scientific or theoretical inquiry, but also for the “salvation of man,” which, according to Avicenna, lies in the purity of man’s soul (Treatise, p. 14): “This purity of the soul is attainable by contemplating the pure form and avoiding this-worldly inclinations. And the way to these two is science. And no science which can not be examined by the balance of logic is certain and exact.” This statement indicates that mastering the science of logic is, in Avicenna’s view, a necessary condition for the knowledge of any discipline, be it theoretical or practical. In either case the purpose is knowledge: knowledge of the truth (ḥaqq) in the former case and of the good (ḵayr) in the latter (Madḵal, p. 149).

This raises a question concerning Avicenna’s views on the age-old debate about whether logic is a part or an instrument of philosophy. Avicenna argues (Qīās, p. 10) that there is no contradiction (tanāqoż) between those who maintain that logic is part of philosophy (i.e., the Stoics) and those who hold that logic is an introduction to and a tool for philosophy (i.e., the Peripatetics). The answer to this question depends, according to him, on one’s definition and understanding of the subject matter of philosophy, and any quarrel about this issue is both meaningless (bāṭel) and futile (fożūl) (Madḵal, p. l6).

As for the subject matter of logic, Avicenna maintains that the secondary intelligibles (or concepts) (al-maʿānī al-maʿqūla al-ṯānīa) are the proper subject matter of logic (Elāhīyāt I, p. 10).

These secondary concepts depend on the primary concepts, Avicenna argues. By this he means that the former come about by abstraction (tajrīd) from the latter, i.e., they become ideas remote from the particular content which they have as primary concepts. The secondary concepts, in other words, are remote from the sensible forms (hayʾāt maḥsūsa) or from the particular material objects (ʿEbāra, p. 2, line 1). The primary concepts, on the other hand, are associated with the sensible material objects of which they are pictures (ṣowar) (ibid., p. 1, line 1).

Logic and language. The distinction between primary and secondary intelligibles occurs in several Arabic logical texts much before Avicenna’s time. As many scholars have already pointed out, it occurs in (the Arabic translation) of Porphyry’s Isagogeas well as in the writings of Fārābī and other Arab thinkers of the tenth and eleventh centuries. Yet, probably due to historical circumstances, it is Avicenna who is credited as the originator of this distinction, which remained a central issue in logical debate for several centuries.

This distinction, to which the modern distinction between object language and metalanguage is related, is of great importance for logicians. First it defines as the subject matter of logic those concepts which, in Avicenna’s language, “have a mental existence that is not attached to matter at all or is attached to non-corporeal matter” (Elāhīyāt, p. 11). These are the secondary concepts and not the primary concepts. The latter, because they are descriptions of the accidental aspects of things, can not be the subject matter of logic.

Secondly, this distinction is an extension and a development of the Aristotelian theme concerning the three modes of discourse—written, spoken, and mental. Avicenna discusses these in the first chapter of his ʿEbāra under the section heading: “On the Relationship Between Things (omūr), Conceptions (taṣawworāt), Spoken Utterances (alfāẓ), and the Written [Form],” thus making the threefold Aristotelian division a fourfold division by adding the dimension of external things. Avicenna describes the relationships between the four modes as follows (paraphrased):

Due to a special faculty with which mankind is equipped (qowwa ḥessīya) external things are imprinted (tartasem) in the mind (nafs, soul). These imprints are present in the mind without the presence of the material object which they depict; this is the stage of abstraction (tajrīd). Thus, things have two modes of existence: an external existence (wojūd fi’l-aʿyān), i.e., the individual material objects, and a mental existence (wojūd fi’l-nafs). The argument then describes the need for a tool to communicate, thus adding the third dimension (spoken). The fourth dimension (the written word) is explained through the need for continuity of ideas (ʿEbāra, pp. 1-2). The third dimension (speech) and its relation to thought (the second mode) is a major theme in many of the logical writings of medieval philosophers, both Arab and Latin, many of whom claim that logicians are supposed to deal with utterances insofar as they signify thought.

According to Avicenna, however, language should on no account be considered an issue for logicians in their logical inquiries. Logicians, he says (ʿEbāra, p. 5) are concerned with utterances (lafẓ) only accidentally (be’l-ʿaraż) and only insofar as these utterances signify the concepts themselves (al-maʿānī anfosohā), which are the proper subject matter of logic. Elsewhere, (Madḵal, p. 22) Avicenna says that logicians need (natural) languages only in order to be able to address logical issues and to communicate with others about these issues. Logic, according to him, does not deal with utterances per se because these are only a tool and can theoretically be replaced by some other device (ḥīla) through which one can express logical relations without the mediation of a natural language. Avicenna criticizes those who think of language as an integral part of logic. By this he refers to the logicians of the tenth century (led by Fārābī) who adopted this view.

Yet, in the same passage of his Madḵal, Avicenna states that “utterances have various modes (aḥwāl) on account of which the modes of the notions corresponding to them in the soul vary so as to acquire qualifications (aḥkām) which would not have existed without the utterances.” From this statement, it is easy to infer—as has A. I. Sabra, for example (p. 763)—that “the secondary concepts, the proper object of logic, not only are reflected in language, but are generated by it.” How can we reconcile these two positions of Avicenna concerning the thought-language relationship?

In the Ešārāt (p. 181) Avicenna modifies his initial position concerning the accidental nature of the relationship between logic and language by stating that languages have a universal side (jāneb moṭlaq) which is not confined to any particular language. It is this universal side of language with which logicians should be concerned. Unfortunately, Avicenna does not explain what counts as a universal feature of a language.

Whether in the final analysis utterances are a subject for logical inquiry or not, however, Avicenna devotes much of his logical theory to the relationship between language and thought or logic.

Utterances can signify either a universal notion ("man" or "animal", each of which is predicated of many individuals) or a particular one ("Zayd", i.e., a particular man). Like all the logicians, he adopts the Porphyrian division of general terms into the following categories: genus (jens), differentia (faṣl), species (nawʿ), property (ḵāṣṣa), and accident (ʿaraż ʿāmm).

The list of five predicables, as these are called, is the subject matter of logic for it includes all the secondary concepts (or, to be more exact, the terms that signify these concepts).

Utterances, Avicenna says (Ešārāt, p. 187; Manṭeq, p. 14) can signify concepts in three different ways:

(1) By correspondence (moṭābaqa), i.e., when a certain term directly signifies the concept for which it was coined or designed (mawżūʿ), as in the term "triangle" which signifies the notion of a three-sided figure or "man" which signifies the notion of a rational animal.

(2) By inclusion (tażammon), i.e., when a concept is included in the meaning of a term. "Man", for example, means and corresponds to the notion "rational animal". Thus both "rational" and "animal" are included in the meaning of "man".

(3) By implication (eltezām), i.e., when the meaning is only implied by the term (it neither corresponds to it nor is it part of its meaning), as in the relationship between the term "ceiling" and the concept of wall (Madḵal, p. 43; ʿEbāra, p. 3).

Having dealt with individual terms, Avicenna next discusses how these terms combine to produce sentences. Like all logicians, however, his concern is not with the syntactical features of sentences as such, but rather with the statements (qażīya,qawl jāzem) that these sentences represent.

A statement is either predicative (ḥamlīya) ("S is P") or conditional (šarṭīya). The latter is a combination of two or more predicative statements and can be either a conjunctive conditional (šarṭī mottaṣel) (if . . . , then . . .) or a disjunctive conditional (šarṭī monfaṣel) (either . . . or).

Avicenna’s explanations of the different types of predicative statements, the division according to their quality, quantity and modality, and finally their different combinations in a syllogism are Aristotelian. His treatment of these same issues in relation to the conditionals relies heavily and perhaps exclusively on the Stoics who developed this branch of logic. Yet, Avicenna exhibits a superb understanding of these problems and presents them in a very coherent, systematic and clear style to the student of logic. His writings are, no doubt, the encyclopedia of Arabic logic.



Works by Avicenna: al-Šefāʾ, al-Manṭeq, Cairo, I: al-Madḵal, ed. G. C. Anawati et al., 1952; II: al-Maqūlāt, ed. G. C. Anawati et al., 1959; III: al-ʿEbāra, ed. M. Ḵodayrī, 1970; IV: al-Qīās, ed. S. Zāyed, 1964; V: al-Borhān, ed. A. ʿAfīfī, 1956; VI:al-Jadal, ed. A. Ahwānī, 1965; VII: al-Safsaṭa, ed. idem, 1958; VIII: al-Ḵaṭāba, ed. M. S. Sālem, 1954; IX: al-Šeʿr, ed. idem, 1969. Al-Šefāʾ, al-Elāhīyāt, ed. G. C. Anawati and S. Zāyed, Cairo, 1960.

Al-Najāt, ed. Kordī, 2nd ed., Cairo, 1938. Al-Ešārāt wa’l-tanbīhāt, ed. S. Donyā, Cairo, 1960.

Manṭeq al-mašreqīyīn, Cairo, 1910. Ketāb al-ḥodūd, ed. and French tr. A. M. Goichon, Cairo, 1963.

Treatise on Logic, ed. with Engl. tr. of pt. 1 of the original Persian Dāneš-nāma-ye ʿalāʾī by F. Zabeeh, The Hague, 1971.

Fī aqsām al-ʿolūm al-ʿaqlīya in Tesʿ rasāʾel, Cairo, 1908; Engl. tr. in Medieval Political Philosophy, ed. R. Lerner and M. Mahdi, New York, 1972, pp. 95-97.

Secondary sources: S. M. Afnān, Avicenna. His Life and Works, London, 1958.

G. C. Anawati, Moʾallafāt Ebn Sīnā, Cairo, 1950.

W. Gohlman, ed., The Life of Ibn-Sina, Albany, N.Y., 1974.

K. Gyekye, “The Terms "Prima Intentio" and "Secunda Intentio" in Arabic Logic,”Speculum 46, 1971, pp. 32-38.

A. I. Sabra, “Avicenna on the Subject Matter of Logic,” The Journal of Philosophy77, 1980, pp. 746-64.

N. Shehaby, The Propositional Logic of Avicenna, Boston, 1973.

For comparison with Islamic logicians who dealt with similar problems see Ebn al-Ṭayyeb (980-1043), Commentary on Porphyry’s Eisagoge, ed. K. Gyekye, Beirut, 1975.

Ebn Sowār (943-1020), “Commentary on the Arabic Translation of Aristotle’s Commentary,” in Manṭeq Aresṭū, ed. ʿA. Badawī, Kuwait and Beirut, 1981, 1, pp. 77ff.

Fārābī (d. 950), Eḥṣāʾ al-ʿolūm, ed. ʿO. Amīn, 3rd ed., Cairo, 1968.

Idem, Šarḥ le-ketāb Arestūṭālīs fi’l-ʿEbāra, ed. W. Kutsch and S. Marrow, Beirut, 1960.

Idem, Ketāb al-ḥorūf, ed. M. Mahdi, Beirut, 1970.

Yaḥyā b. ʿAdī (893-974), “On the Difference between Philosophical Logic and Arabic Grammar,” ed. G. Endress, in The Journal of the History of Arabic Science 2, 1978, pp. 38-50.

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ابن سینا، متافیزیک avicenna,metaphysic ebn e sina,metaphysic 



(M. E. Marmura)

Originally Published: December 15, 1987

Last Updated: August 17, 2011

This article is available in print.
Vol. III, Fasc. 1, pp. 73-79