Can Ibn Sina Speak of the Simplicity of the Soul?

Can Ibn Sina Speak of the Simplicity of the Soul?


2019 30. cilt – 1. sayı


Shams INATIa

aDepartment of Theology and Religious Studies, Villanova University College of Liberal Arts and Sciences, Villanova, PA, USA


Bu makalenin amacı, İbn Sina’ya göre ruh kavramının basitliği ifade edip etmediğini araştırıp ortaya koymaktır. Konu, ruhun basitliğinin İbn Sina için bir ebedilik durumu olduğu, dolayısıyla bölünmeyen ve yok olmayan ve bunun da metafizik iyilik durumu anlamına gelmesinden dolayı önemlidir. İbn Sina tarafından “nefs” kavramına atfedilen anlamlar, bu makale içerisinde anlatılmaya çalışılacaktır. Bitkisel, hayvanî ve rasyonel nefs bu büyük düşünür tarafından kullanılan başlıklardandır. İbn Sina özellikle rasyonel ruhun bir bedende zuhur etmeden önce, bir vücut içerisinde iken ve vücuttan ayrıldıktan sonra varlığını idame ettirdiğinin özellikle altını çizmiştir. Bu çalışmada, İbn Sina’nın öne sürdüğü ruhun basit bir varlık olduğu, fakat bu basitlik durumunun herhangi bir maddiliğe (çokluk ve ayrışma kaynağı) bağlı olmadan varlığını idame ettirebilen rasyonel ruha ait olabileceği konusu analiz edilecektir. Rasyonel ruh, beden içerisinde iken o bedeni kontrol ederken onun fiillerinden etkilenmeyen, bağımsız bir varlık olarak var olmaktadır. Aklî nefsin, ruhun beden içindeyken edindiği güçlerin farklı kısımları olarak tasvir edilen noktalar onun son derece basit ve bağımsız doğasına ait olan farklı özelliklerin ta kendisidir. Dolayısıyla İbn Sina’nın kullandığı “nefsin” farklı anlamları arasında gezinirken konuyla ilgili sıklıkla karıştırılan ve anlaşılamayan noktaların açıklanmasını amaçlayan bu makalenin sonunda, aklî nefsin İbn Sina’ya göre basit bir varlık olarak kaldığı ve ebediliği güvence altına alan bir yapı olduğu sonucuna ulaşılmıştır.

Anahtar Kelimeler

İbn Sina; ruh; basitlik; sonsuzluk; rasyonel ruh


The aim of this article is to research if Ibn Sina’s concept of the soul is simple. The issue is significant as it shows the view of Ibn Sina for whom simplicity means eternity which means lack of division and destruction and which is connected to metaphysical goodness. It will be attempted to distinguish different meanings in which “soul” is used by Ibn Sina who preffered using the concepts of plant, animal, and rational soul for referring it. He specifically points out that rational soul can exist before existing in the body, in the body, or after separating from it. The paper asserts that for Ibn Sina soul is simple entity, but only in the sense of the rational soul, which is free from any materiality (the source of multiplicity and disintegration). When rational soul is in the body, it exists as a unity unaffected by the roles it plays in controlling the body. What is described as parts or powers of the rational soul during its lodging in the body seems to be nothing other than various aspects of it that do not affect its independent simple nature. Thus, shifting through the various senses of “soul” used by Ibn Sina and clarifying misleading and confused statements about the subject, the paper concludes that, the rational soul remains in Ibn Sina’s thought as a simple existence and a guarantee of eternity.


Ibn Sina; soul; simplicity; eternity; rational soul

Much has been said by Ibn Sina and by others about the role of the soul in Ibn Sina’s philosophy. But one thing still deserves further investigation: Whether the soul in his view is single or multiple. This issue is of the utmost importance, because if the soul is to be eternal and,  hence,  metaphysically  good,  as Ibn Sina asserts, then it has to be simple. This is because what is multiple is subject to division and, therefore to destruction and, hence, metaphysical evil. In other words, if it cannot be proved simple, it cannot be proved eternal and good.

Firstly, it should be pointed out at that the discussion in this article is based primarily on two of Ibn Sina’s works: Remarks and Admonitions (al-Ishārāt wat-Tanbīhāt) and “Poem on the Soul” (al-Qaīda al-`Aynīyya). Analyzing other works of Ibn Sina would require writing a book as he has various significant points to be mentioned. So, it is determined that these two works are sufficient to prove the thesis of this article.

Before addressing the issue of the simplicity of the soul, it is important to note that the soul, according to Ibn Sina, seems to exist in one of three states: Prior to joining the body, dwelling in the body, and after its departure from the body.[1]

In particular, Ibn Sina’s “Poem on the Soul” speaks with clarity of the soul’s existence before the body, which is like a heavenly state.[2]We are not given much information about the details of its existence in that state. For example, is it completely by itself and free from being attached to any celestial body, or is it attached to a celestial body? If independent of a celestial body, where is it? We understand that the celestial sphere consists of celestial bodies with individual souls and intellects. Does the soul that descends to join the human body, belong to a celestial body or another type of soul?

If the former is true, does the celestial body lose a soul when its soul descends to a human body? This is impossible as every celestial body is described as a living being that is eternally moved by its soul. The celestial souls are also very small in number, as are the celestial bodies (which are ten, according to Ibn Sina), but the human souls are various. If the latter, then where exactly was the soul before it joined the human body? We are not given much detail about its existence in that state. But it is described symbolically as “a white dove” in “the highest place,” free and happy before its imprisonment in this worldly “cage.”[3]

The “white dove” description seems to refer to its purity and innocence and the comfortableness of its place to its celestial existence. Except heavenly bodies, everything is pure and celestial according to Ibn Sina; as everything is free from matter, they are simple. Therefore as in its existence before entering that ‘cage’ the soul is unmixed with matter, we can assume that it has a simple form. According to Ibn Sina, multiplicity and division appear only with attachment to matter.

In other words, Ibn Sina claims that the soul is nonmaterial, simple, and universal before it descends to earth. After all, one claim in the “Poem on the Soul” is that, one of the reasons for descending to earth is to learn about particular material things in our world that the soul did not know before.[4] If it were equipped with characteristics, such as particularity and materiality, which are the attributes of the beings in our world, perhaps it might have had the knowledge of our world without descending.

According to Ibn Sina, the soul is nonmaterial and simple in the state of preexistence, but where exactly is it? It can only be assumed that in its preexistence, the soul is an intelligible at the level of agent intellect, at the level of the lowest celestial intellect or the intellect of the moon.[5] This is because the agent intellect is said not only to bestow knowledge on the human theoretical intellect, as we will see later, but also to it is the giver of forms (wāhib auwar), and the soul is described by Ibn Sina as a form: The form of the body. No being can give what it does not have, as the Arab saying asserts: “A thing cannot give what it lacks” (fāqid ash-shay’ lā yu͑ṭīh). Thus, the agent intellect must involve forms in order to be able to provide them to our world. This intellect is said to give all of the forms to our world, including the form of the human body, the human soul. This happens when the body is ready to receive its specific or proper form.

When the body has its proper form, the form also has a convenient body. Therefore, for Ibn Sina transmigration is not possible, because a soul inhabits only the body for which it is specifically fashioned to manage and with which it has a special relationship.[6] This view is different from that of Plato and Plotinus, who believed that the soul changes bodies the way a human being changes robes. When what we refer to as “soul” is independent of the body, it is not called “soul” in the real sense. It is called so only on the basis of its relationship with the body; as long as it is the form of the body and its manager.[7] So when it is in the agent intellect, and prior to its attachment to a body, it is best to call it “intelligible,” which is a soul in potentiality in the sense that it can attach to a body and become its form and manager.

In any case, if the soul is indeed simple in its prior existence, what happens to this simplicity when it joins the human body and its multiple facets and when it departs from it? Any response to this issue requires a full understanding of the nature of soul in the body and what happens to it after it leaves the body.

As I have pointed out in some of my earlier writings,[8] Ibn Sina uses the term “soul” (nafs) in more than one sense. Besides celestial souls, he uses the term to refer to the soul of human being (an-nafs al-basharīyya) which has three main parts: the plant or vegetative soul (an-nafs an-nabātīyya), the animal or sensitive soul (an-nafs al-ayawānīyya), and the rational soul (an-nafs an-nāiqa). The first two constitute the non-rational soul. Ibn Sina also calls the third ‘the human soul’ to stress the point that human soul is essentially rational.[9]

Let’s now detail the natures of these different types of souls, their powers, and their functions to see whether simplicity is still a feature of any of them, and if it is where exactly is it?

In itself, the plant soul has three powers responsible for three functions: Nourishment, growth, and reproduction. This bodily soul manages the nutritive elements in order to replace what was already decomposed, to help increase the growth in order to complete its constitution, and to prepare for its continuity through its “preservation and generation” by means of “a surplus that is prepared as the matter and principle for another individual.”[10] Ibn Sina observes that these three powers come to an end one after another, thus leaving the plant soul lifeless.

In other words, sooner or later the plant soul dies out, and whatever dies out must be complex in nature. It is clear from the above that the plant soul must be multiple in nature and, therefore, divisible and destructible. For in the first place, this soul cannot be simple, as it belongs to the body, which is by nature multiple and divisible: “Every single body and every power in a body is divisible.”[11] Therefore, the plant soul and its powers must be multiple and divisible as they essentially belong to the body.

On the other hand, animal soul is also said be separated into sensitive and locomotive powers, each of which separates into further powers responsible for different functions.

The sensitive power in turn separates into external and the internal senses. External senses are the well-known five senses: Touch, smell, taste, hearing, and sight (the first three are said to be necessary for survival; the last two are necessary for well-being). Internal senses are also divided into five categories: Common sense, representational faculty, imagination, estimation, and memory. Ibn Sina elaborates on the internal senses in many of his writings, such as the Third Class of the Physics of Remarks and Admonitions.[12]

The locomotive power involves forces that give orders to other things to move in a certain direction and arrange them to follow the orders and move accordingly. The former are the appetitive or desiderative faculty and the irascible faculty. The appetitive faculty gives orders to move towards an object imagined or thought to be pleasurable; while the irascible faculty gives orders to avoid and stay away from an object imagined or thought harmful. The appetitive faculty gives orders to the nerves to cause relaxation in the muscles. On the other hand, irascible faculty employs the nerves to tighten the muscles.

“As for the voluntary movements, they are more animated [than the movements of the plant soul]. They have a principle that decides and determines, and submits to, and is acted upon by the imagination, the estimation, or the intellect. The irascible power produces harm or desiderative power that brings about what is necessary or beneficial for the animal which proceeds from it. This is obeyed by the moving powers that are cast in the muscles and that serve the power that gives orders.”[13]

 It is clear that the animal soul also cannot be simple considering its material presence exhibited in its spreading its multiple physical branches and their functions throughout the body. Thus, we see that the plant and animal souls are bodily, complex, and divisible in nature.

Ibn Sina thinks that it is only in the sense of a rational entity that the human soul is distinct, simple, and indivisible. But could it be so when this type of soul, which is also said to have two intellects, operates in the body? This type of soul is divided into two categories as Practical intellect (al-͑aql al-͑amalī) and Theoretical intellect (al-͑aql an-naarī)in addition to a number of powers that can perfect it. In order to answer the above mentioned question, we must first try to understand what these two intellects and their powers are and how the rational soul operates in the body.

Though Ibn Sina speaks of two intellects of the human rational soul, he describes these intellects as nothing other than two sides or aspects of the same thing: One side of the rational soul that faces downwards in order to manage the human body through moderation and order, and another side that faces upwards in order to receive universal knowledge. The former or practical intellect is said to be the power responsible for managing the body through inferring “the necessary, particular human affairs that must be done in order to attain this, the chosen purposes from primary premises, well-spread premises, and experiential premises.”[14] The latter or the theoretical intellect, on the other hand, provides “the universal opinion from which the soul moves to a particular state.”[15]

Additionally, theoretical intellect has specific powers which help it perfect itself by recapturing its essence as an actual intellect (͑aql bil-fi ͑l). Ibn Sina views these powers not as separate entities or things, but as states or aspects of the same thing.

The first state or power may be compared to the Platonic receptacle, in that it is empty of forms or intelligences, yet is prepared to receive them. Because of this, some people may refer to it as “material intellect” (͑aql hayulānī). However, like all the states of the rational soul, this state has nothing to do with matter. Ibn Sina refers to it as “the niche,”[16] perhaps because it is empty or void of the forms which it can receive.

When the primary intelligences are imprinted on the first state, a second state or power appears. This second state or power, the habitual intellect (al-ʿaql bil-malaka), is also referred to as the “glass” prepares the soul for acquiring “the second [intelligibles], either by thought which is the olive tree when it is weak, or by intuition which is the oil when it is stronger than that.”[17] Intuition is described as “the noble and actual power” of the habitual intellect; it is said to be “saintly,” and “whose oil almost lights up even without being touched by fire.”[18]

A third and then a fourth state appear in the soul. The third state is s state of perfection obtained by the soul when it actually acquires the intelligibles, “in a manner where they are viewed as represented in the mind. This is a light upon a light.”[19] In the fourth state, the soul can “obtain the already acquired intelligible, which had been achieved, as that which is viewed whenever the soul desires [to do so] without need for acquisition. This is the lantern.”[20]

Ibn Sina refers to this perfection as “acquired intellect” (ʿaql mustafād), and to this power as “actual intellect” (ʿaql bil-fiʿl). The agent intellect (al-ʿaql al-faʿʿāl) is the one that brings out the material into habit and habit into complete actuality. The agent intellect is compared to “the fire.”[21] 

But how does the agent intellect which is the intellect of the moon and above our world bring out the material into habit and habit into full actuality, which are states of the theoretical intellect dwelling in the sublunary sphere? I understand Ibn Sina to say that the agent intellect can do that in one of two ways, the prophetic or philosophic way.

Through the prophetic way, the agent intellect, which is compared to the sun or fire, sheds its light on the theoretical intellect, bestowing on the intelligibles or forms it contains. Thus, it illuminates the theoretical intellect without any effort of the individual. From there, the intelligibles or forms descend to the human imagination, where they take on a symbolic appearance. With that, the individual who receives such symbolic or concealed appearances in the imagination can convey these to others only through a symbolic language: The religious commoners and majority of people.

In terms of the philosophic way, it requires some preparation on the part of the individual. By means of the external senses, one must grasp the universal aspects of things and transmit these sensations to the internal senses, where eventually they settle in the imagination. There they are somewhat purified from the nature of external material objects, in the sense that they are now universals but still covered by individuality and materiality. Thus, the objects of imagination are half true and half false. The role of the agent intellect here is to shed its light, not on the theoretical intellect directly, but on imagination; thus, making its objects visible to the theoretical intellect, which is still a pure capacity. The objects of the imagination are then reflected on the material intellect or pure theoretical capacity. As this theoretical capacity is by nature nonmaterial, it cannot grasp any object except for the nonmaterial ones. Therefore, the only things from the visible objects of the imagination it can accept and mirror is their non-material and universal aspects.

When the theoretical intellect is fully actualized by the light of the agent intellect, it frees from the body and continues in a spiritual heaven, reflecting the eternal aspects of the universe. Such an intellect or soul is also completely happy since it has fulfilled the human desire it has developed for acquiring the knowledge of the eternal and simple aspects of the universe. If it knows that such knowledge is good for it, desires it, but does not attain it, it continues to exist in a spiritual hell. 

Despite various detailed sides of the rational soul, including its practical and theoretical aspects and the various states or powers of its theoretical intellect, the rational soul remains single in Ibn Sina’s view. These aspects and states or powers are nothing but functions and capacities of the same thing. Therefore, the rational soul is in essence simple, good, and eternal. While in the body, it is unaffected from it; rather, it manages the body through its practical side and it mirrors the reflections of the agent intellect by turning on the light of the agent intellect, by transforming its theoretical side into actuality, and perfection. So while in the body, the rational soul connects with it, not through any material means directly, but through acting as a receptacle to the light of the agent intellect. 

According to al-Farabi the human rational soul that does not fulfill its ultimate objective of acquiring knowledge of the eternal aspects of the universe will disintegrate, because it will not fulfill its nature; on the other hand, according to Ibn Sina, such a soul will not disintegrate as it is simple and indestructible by nature. However, it remains in an eternal spiritual hell if it knows that knowledge is good for it, desires such knowledge, but is unable to obtain it. If such a soul does not know that such knowledge is good for it, it will not be in any spiritual hell or heaven but in what one may call “an intermediate state.” It remains in this condition, according to Ibn Sina, except if it manages to attach itself to a celestial body whose senses it can use to acquire the knowledge it can in the human body.[22] The reason it attaches itself to a celestial body is that after it separates from its human body, it cannot return to any human body and use the bodily senses to complete itself, since -as previously mentioned- transmigration is impossible according to Ibn Sina.

In other words, regardless of the state in which the human rational soul finds itself after death, it remains simple once it is completely free from physical attachments.

In order to draw the final conclusion as to whether or not Ibn Sina can speak of the simplicity of the soul, we must keep his following considerations in mind: (1) The above-mentioned three states in which what is referred to as “soul” is found are; the state prior to its existence in the body, its existence in the body, and after its separation from the body; and (2) The entity referred as “soul” is not really so if it is separated from the body. This is because by definition a soul is the form of a body and its manager. In other words, because of its relationship to the body that entity is called “soul.”  

In the first state, it is simple, as it is an intelligible and unmixed with matter. The second state, which is the most difficult state to comprehend, is considered by Ibn Sina would as simple, since it remains in its nature unmixed with matter and unreceptive to any material thing. It is said to dwell in the body and manage it, but without having a direct physical relationship with it. Rational soul in the human body is not a part of the body, but more like a spiritual instrument which facilitates and transmits the light of the agent intellect to imagination and receives the objects of the imagination and then transmits them to the agent intellect after it strips them of their materiality and individuality.

In the third state, it is separated from the body and, therefore, simple. Even when it is said that some souls remain attached to some bodies after separating from their worldly connection, this does not mean that they become material in nature. Rather they use such bodies to acquire for some sense of information which can be used as the basis for acquiring knowledge and, hence, climbing to the world of intelligibles and happiness.

It has been argued here that Ibn Sina can speak of the simplicity of the soul. However, his use of the expression “soul” in so many different senses makes it difficult to understand his various statements about the soul, some of which can be misleading. It would be clearer if he had referred to the three states of the rational soul as follows: Preexisting soul or soul in potentiality, existing soul or soul in actuality, and post-existing soul or past soul. Moreover, it would be less confusing if he hadn’t use the term “soul” as the plant and animal powers. These are bodily organs, not intelligibles that have a relationship to the body or forms of a body that manages it throughout the relationship. Still, under all the misleading and confusing remarks, the idea remains that only the rational soul is simple throughout its existence and, thus, indestructible. So yes, Ibn Sina can speak of the simplicity of the soul but only in its rational sense and only after remove the confusion and misleading statements about the concept of the soul mentioned above.


[1] It is worth noting here that Ibn Sina seems to waver on whether the soul exists before the body. We will not discuss this controversial issue here as it is beyond the purpose of this article. We will only assume that the soul exists before the body according to him as his “Poem on the Soul”,which is one of his authentic works suggests that.

[2] “Poem on the Soul,” in Avicenna on Theology, Westport, Hyperion Press, Conn 1979, pp. 77-78.

[3] Ibid.

[4] Ibid.

[5] Muslim philosophers raised the Aristotelian active intellect from residing in the human being to the celestial sphere and gave it a divine status that plays an epistemological and existential role in our sublunary world.

[6] The reason for Ibn Sina’s rejection of the theory of transmigration is that to him, “the coming into existence of any human or animal body necessitates the simultaneous emanation of a soul from the separate or higher causes for that body.”“Risāla fī an-Nafs wa-Baqā’ihā wa-Ma ͑ādihā,” in Awāl an-Nafs, ed. Ahmad Fuad al-Ahwani, Dār Ihyā’ al-Kutub al-Arabīyya, Cairo, 1952, p. 106. If this is the case, then if, for example, a soul leaves Albert’s body and returns to Paul’s body, then Paul’s body will have two souls: the one that emanated to it simultaneously with its coming into existence and the other that came to it from Albert’s body.  However, “it is impossible for one body to have two souls. After all, the function of the soul is to administer the affairs of the body.” Shams Inati, Physics and Metaphysics (Phy and Meta), Columbia University Press, New York 2017,  Third Class, Ch. 5. See also “Risāla fī Ma͑ rifat an-Nafs an-Nāiqa”, p. 186. One of the main arguments Ibn Sina introduces against the theory of transmigration is this. If two souls dwell in a body, only one of these souls would be this body’s administrator; the other would not and, therefore, would not be this body’s soul. (For a detailed discussion of Ibn Sina’s rejection of the theory of transmigration, see Shams Inati, Ibn Sina and Mysticism, Kegan Paul, London 1996, pp. 23-24, 78.

[7] “It is called soul only inasmuch as it has a relationship to the body.”

[8] See, for example, Shams Inati, “The Soul in Islamic Philosophy”, in Routledge Encyclopedia of Philosophy, volume: 9, London 1998, pp. 40-44.

[9] Ibid.

[10] Ibid.

[11] Phy and Meta, Third Class, Ch. 16.

[12] Phy and Meta, Third Class, Ch. 9.

[13] Phy and Meta, Third Class, Ch. 25.

[14] Phy and Meta, Third Class, Ch. 10.

[15] Ibid.

[16] Ibid

[17] Ibid.

[18] Ibid

[19] Ibid.

[20] Ibid.

[21] Ibid.

[22] For Ibn Sina’s view on the possibility of the soul attaching to a celestial body, see Ibn Sina and Mysticism, pp. 20-29, 78.