Mulla Sadra's Realism on The Principle of Ittihad al-'Aqil wa al-Ma'qul: A Response to Modern Realism

This article attempts to show Mulla Sadra’s model of realism by tracing it through his philosophical principles, especially the principle of Ittihad 'Aqil wa Ma'qul (subject-object unity). Furthermore, the study of the Sadra realism model, which is based on the principle of Ittihad 'Aqil wa Ma'qul, is presented to respond to fundamental epistemic-ontological issues, namely the relationship between the subject’s consciousness and external objects, in order to strengthen belief in the nature and existence of external reality, which is independent of contamination of the subject's mental decisions (mind-independent reality). How does the subject's consciousness relate to external objects? This problem is still an anxiety and has not been resolved by modern philosophers who focus on the discourse of perception, giving rise to various schools of realism, which are represented by two major schools: direct realism and indirect realism. By overcoming these epistemic problems, ultimately, this effort leads to the confirmation of Mulla Sadra's more original and comprehensive model of realism. This paper is attempted using a critical-analytical method, namely analyzing Mulla Sadra's philosophical ideas on the Ittihad 'Aqil wa Ma'qul principles and the views of modern realism by focusing on the issue of perception. The conclusions drawn from the results of the analysis of the Ittihad 'Aqil wa Ma'qul were used as a basis for responding to modern realism as well as an affirmation of Mulla Sadra's style of realism.


Introduction
Reality, or something that is real (actually exists) in the history of philosophy, has become one of the most fundamental and important issues because it directly highlights the object of philosophical study itself.From the classical-Hellenistic era to the present, in the periodization of the development of philosophy and science, this issue is not without controversy.At least the scientific and philosophical debate about this was initiated by the sophists and philosophers such as Socrates and Plato.The above differences were later known as the roots of realism by philosophers, namely the belief in the existence of something real or real (asl al-waqi') in the external realm without depending on mental cognitive conditions (mind-independent reality) (Bunge, 2006) and anti-realism in the form of sophism by the Sophists.Furthermore, the discussion about reality continued in the transitional era between Plato and his student, Aristoteles, which continued to color the world of philosophy even into the Middle Ages.The debate is based on the issue of 'universals' (archetypes: the essence or substance of everything); does the 'universal' actually exist in the material realm or in another realm?Plato believed that 'universals' only exist in the realm of ideas, namely the immaterial realm that transcends the material realm.For this reason, Plato's understanding is called idealism, as opposed to the realism proposed by Aristoteles, who thought that real 'universals' existed in the material world.Then Aristotelian realism more dominantly colored the realm of philosophical thought in the Middle Ages, giving rise to a new form of rejection known as nominalism (Sudarminta, 2002).
In the modern era, since the shift in the starting point of philosophical attention from the ontological trend to the epistemological trend (Hamdani, 2016), the perspective on studying reality has broadened, and it falls in line with the style of debate.In this era, the first things to be resolved are problems related to elements of perception, such as sources, processes, limits, and values of knowledge, before making decisions about the ontological aspects of reality.In other words, belief in the existence of a real object really depends on the extent to which the subject's mentality is able to reach it.Therefore, the fundamental question that must be answered is whether the subject is able to perceive or know the object or reality as it is.If the answer is positive, then the next question is: how does the subject mentally do it?These questions clearly boil down to perceptual or epistemological problems.
Still in the context of modern philosophy, since the beginning of the past century, scholars have identified the struggle between subjectivism and realism as one of the important themes in its discourse (Lewis, 1913;Smith, 1908).This debate has continued throughout the twentieth century, with the increasing development of philosophical orientations focused on the exploration of subjective consciousness, such as phenomenology, existentialism, and the influence of philosophical psychoanalysis.Nevertheless, the strong dominance of scientific reason to the present day has led some philosophers to support the truth of realism (Bunge, 2006).For them, science is grounded in realism.In other words, rejecting realism means rejecting science.The perspective commonly referred to as scientific realism has been widely criticized up until now (Boge, 2023;Siegemund, 2020).Nevertheless, if we are seeking a way to bridge the gap between subjectivism and realism, mere criticism of realism-including scientific realism-is not sufficient.
The development of philosophy and science, especially in the modern Western world, was accompanied by the emergence of many thoughts, including regarding the issue of perception, especially regarding responses to questions about reality or real objects, as mentioned above.These views differ from each other and are even framed in polemics that continue past polemics.Philosophical ideas regarding the issue of reality in the modern era, if broadly classified, will fall into two major currents, namely realism and modern antirealism.Modern anti-realism is divided into several epistemological subthoughts, such as subjectivism, idealism, skepticism, and relativism.All types of anti-realism stand on the principle of rejecting the belief in the existence of an independent reality or the possibility of perceiving it.Modern realism is divided into two major schools, namely direct realism and indirect realism, and each of the two is then separated into several schools of realism (Foster, 2000).
In principle, direct realism believes that the physical world is independent, and what we perceive directly are things about the physical objects themselves (Hirst, 2006).The subject or perceiver believes in the existence of physical objects, and the subject's perception or sensory knowledge is the physical object itself, not a representation or idea about the object.The presence of a physical object is not inferred from other symptoms directly experienced or known by the subject.Meanwhile, indirect realism is the opposite of direct realism and believes in the existence of an independent reality and the mental ability to know it, but this type of realism emphasizes that it is impossible for a subject to perceive an object without the intermediary of sensory data (sense data), because what is perceived directly is the data.Sensory data are not physical objects.The subject is only able to perceive physical objects indirectly.Therefore, RTL places sensory data between perception and physical objects.These sensory data function as representations of physical objects to be perceived directly by the subject (Bunin and Jiyuan, 2004).
According to the author, the two major schools of modern realism and their splinters, if reviewed further, have not provided adequate explanations and arguments so that they can lead to strong beliefs because they still leave room for several issues, including: whether what is present in the subject's mind is an object or physicality itself, so that the perceptions obtained truly reflect reality as it is as claimed by direct realism?What evidence of identity between object and perception exists in the subject's mind?Can sensory data really represent factual objects, as claimed by indirect realism?Isn't the sensory data obtained from the senses only in the form of images and not meaning or substance?Because the five senses are only able to perceive appearance, not meaning or substance?
These problems require a comprehensive approach and analysis to be able to lead to beliefs about reality, starting with issues of perception.In this case, the author tries to propose a philosophical idea that, according to the author, is quite unique and original from a Muslim philosopher of the 16th century AD, a philosopher who had formulated a new school and perfected previous philosophical schools such as Platonism and Aristotelianism (peripatetic).
It was Mulla Sadra, a Persian philosopher who had synthesized several previous treasures of thought, Greek and Islamic philosophy (Peripatetics and Illumination), Sufism, and Islamic theology, into a new school, which he called Hikmah Muta'aliyah (wisdom or great wisdom).Some of his unique philosophical principles, such as 'fundamentality of existence' (asalat alwujud), 'gradation of existence' (tashkik al-wujud),'substance movement' (alharakah al-jawhariyah),'science of husuli and science of huduri','the unity of subject and object' (Ittihad 'aqil wa ma'qul), and others, have become philosophical thoughts that provide solutions to various previously unsolved philosophical problems.Specifically, the principle of'subject-object unity' that is the focus of this article will be elaborated on by the author in order to solve the problems of realism as mentioned above.
The emphasis of this paper in analyzing the issue of realism is on the principle of'subject-object unity', although it is inevitable to occasionally link it with other principles because, in fact, all of the above principles are interrelated.This is at least suspected by the principle of subject-object unity', which can explore the issue of realism from two sides: epistemology and ontology.Mulla Sadra's unique idea, in essence, highlights the issue of identity and correspondence between the object as the known and the perception of the subject as the knower within the frame of the possibility of the subject knowing the nature of things and reality as it is.Based on this principle, the gap that separates subject and object, thus giving room for doubt regarding belief in actual reality, is eliminated with the argument that in true knowledge there is a union between subject and object, or Ittihad al- 'aqil wa al-ma'qul (Sadra, 1410), and this is where the weaknesses of the two major schools of modern realism, direct and indirect realism, are overcome.
Apart from that, this principle also confirms the ontological status of knowledge in the mind.With the principle of 'fundamentality of existence', in Mulla Sadra's view, knowledge is not just a concept in the form of the essence of an object but is a mode of existence that must rely on an existence, namely mental existence (the soul of the subject) itself as a perfection for him.From these two sides, all of Mulla Sadra's epistemological principles are never separated from his ontological principles.Therefore, the principles of epistemology are known as onto-epistemology.
This article attempts to elaborate on the principles of Mulla Sadra's philosophy, especially the principle of'subject-object unity ' (Ittihad al-'aqil wa al-ma'qul), in order to solve problems in the issue of realism that have not been able to be resolved by the schools of realism.Modernism is represented by direct and indirect realism.By using analytical-philosophical methods, the data contained in Mulla Sadra's works, such as Hikmah Muta'aliyah, and the works of other philosophers that emphasize Mulla Sadra's philosophy, such as Thabathabai with Bidayat and Nihayat al-Hikmah, and so on, will be analyzed and concluded argumentatively-philosophically in order to further respond to the views of modern realism.
Discussions about philosophical realism are important in contemporary scientific developments because they have implications for macrovision, foundations, or paradigms in scientific buildings and scientific research projects.Some researchers put forward the view that to build a harmonious relationship between religion and science, a realist epistemological foundation is needed (Shamsaei and Gholami, 2021).Even though realism in the context of science or scientific realism does not always have to be based on metaphysical realism (Alai, 2023), the combination of these two realisms will still become a coherent vision in a scientific research project.A number of studies on philosophical foundations in education systems and educational research (Aziz, 2023;Norwich, 2019) also highlight the importance of realism.In the context of Mulla Sadra philosophy, some researchers (Hajmohamadi, 2020;Herman and Yusop, 2021) also see that realism in this philosophical system has a positive role in building an Islamic macro framework for viewing humanism, both in the context of individuals and society.In the core of philosophical studies itself, the formulation and arguments for realism are still being developed.An example is the idea of metaphysical realism, which is based on a combination of continental idealism and American pragmatism in the thinking of Nicholas Rescher (Morgan, 2013).In the Islamic tradition, new formulations of realism based on the onto-epistemology of Muslim thinkers, such as Sadra, still need to be developed further.

Reality and portrait realism
Reality as the root of the understanding of realism itself is an important thing that must be revealed first in this article, both in terms of the meaning of words (etymology) and terms (terminology), before looking at the meaning of realism and the variants of the genre that accompany it.
In the book Living Issues in Philosophy, etymologically, the word'reality' comes from the Latin word "reel"-'real' i in English, waqi' in Arabic, and'real' in Indonesian-meaning'real' or 'actual.'The word 'reel' and its equivalents refer to objects or events that are truly real, meaning that they are not just dreams, fantasies, or what is only in the mind (Titus, 1984).
As for terminology, Nicholas Bunin and Jiyuan Yu in the Blackwell Dictionary of Western Philosophy state that reality is the condition or nature of something that is real or that actually exists (what there is) (Bunin and Jiyuan, 2004).However, in its development, the term reality with the meaning of'something that is real' above has been contrasted with several terms according to several aspects of viewing it.Sometimes reality is abbreviated as something that is only an appearance or shadow, not something that is true.Apart from that, sometimes reality is also inverted to something that is illusory, not just an appearance like the antonym above, namely a pure mental creation that does not at all represent objects outside the mind (Bunin and Jiyuan, 2004).
Departing from the terminological meaning above, reality can be equated with several meanings or terms such as 'existence' (being), 'something' (thing / shai'), 'fact' (fact / waqi'), or even 'material objects' by materialism.From the several terms above, those that are closest to the meaning of reality, according to philosophers, are the two initial terms, namely existence and something that is believed to include both material objects such as stones, Hasan, goats, mountains, trees and so on, as well as immaterial objects such as meaning or substance, concepts and theories (Bunge, 2006).
In Islamic philosophy, reality is'dh a t al-w a qi'wa nafs al-amr (external objects and things in themselves, such as concepts and theories) (Thabathabai and Muthahari, 1418).There are even those who differentiate between 'objective reality', namely reality referred to by language and perception, and 'formal reality', namely the mode of reality in the form of language or thought (Bunin and Jiyuan, 2004).
However, along with the development of science in the modern era, especially in the West, the meaning of reality has been reduced to being limited to 'facts' (objects in the external world).At the beginning of his book, Tractatus, Wittgenstein stated that "reality is the totality of facts, not everything (things)" (Wittgenstein, 1922).In fact, reality is material objects (physical objects that can be identified directly by the five senses such as position, size, shape, and solidity/density), especially by materialists, such as stones, wood, animals, plants, and so on.
Based on the meaning of reality above, the meaning of realism is also understood in various ways, although all views on the meaning of reality lead to one core understanding of realism or realism in a general sense, namely the belief in the existence of something real or real (Bunge, 2006).Apart from belief, another characteristic of this understanding is obedience to something real, which occurs without being influenced by the hopes or desires of the mind or mentality.This belief and obedience by some philosophers for hundreds of years have been maintained by the total skepticism of the Sophists, the hypocritical sense of reality behind appearances by the empiricists-positivists and materialists, the cult of absolute mental abilities by the subjectivistsidealists, and other challenges from variants of anti-realism.
In historical records, the meaning of reality experiencing dynamics, along with the emphasis on philosophical attention undergoing revolution in the modern era, has become an important factor in the style of modern realism, which focuses on issues of perception, thus forming varied schools of realism in the spirit of criticism.
Several scholars have classified forms of modern realism, including John Foster and RJ Hirst above.Modern realism is broadly divided into two forms: direct realism and indirect realism.Several schools of realism can be categorized into these two major forms of realism.For example, Naive Realism, Mediated Direct Realism, and Scientific Realism are included in Direct Realism, while Idealist Realism, Representationalist Realism, Representative Realism, Causal Theory Realism, Sensory Data Representative Realism, Perceptual Realism, Phenomenological Realism, and Conceptual Realism are included in Unrealism.All of these schools of modern realism will not be touched on specifically one by one and will only highlight in general direct and indirect realism.

Direct Realism
In general, direct realism states that perception is a direct awareness, a confrontation, or direct contact with an external object.This understanding claims that the physical world is independent and that what we perceive directly are the particulars of the physical objects themselves (Hirst, 2006).The subject or perceiver believes in the existence of physical objects, and the subject's perception or sensory knowledge is the physical object it self, not a representation or idea about the object.The presence of a physical object is not inferred from other symptoms directly experienced or known by the subject.Naive realism and scientific realism are derivatives of direct realism, with their respective aspects and points of view

Indirect Realism
Indirect realism is the opposite of direct realism (RL).This type of realism recognizes reality or physical objects that are independent of the perceiving subject, as RL also believes, but is different from RL, which assumes that what is perceived is the physical object itself and directly.Meanwhile, RTL considers that it is impossible for a subject to perceive objects without the intermediary of sensory data (sense data), because what is perceived directly is sensory data, not physical objects.The subject is only able to perceive physical objects indirectly.Therefore, RTL places sensory data between perception and physical objects.These sensory data function as representations of physical objects to be perceived directly by the subject (Bunin and Jiyuan, 2004).Idealist Realism, Representational Realism, Representative Realism, Causal Theory Realism, and Sense Data Representative Realism, Perceptual Realism, Phenomenological Realism, and Conceptual Realism are variants of RTL.

Theories of Perception Mulla Sadra: Ittihad 'Aqil wa Ma'qul
Ittihad al-'aqil wa al-ma'qul, which will hereinafter be referred to in the Indonesian translation as Subject-Object Unity (KSO), is Mulla Sadra's unique idea in the realm of epistemology, although it still touches on ontological aspects, which, according to some great Muslim philosophers who followed, were a synthesis of the epistemology developed by the philosophy of the Peripatetic School, Illumination (Suhrawardi), and Mysticism ('irfan).Mulla Sadra's ideas attempt to explain the status of knowledge about the nature of an object, including its ontological status for the subject when perceived.This idea in the history of philosophy is actually rooted in what was initiated by the Greek philosopher Porporius (232-304 AD), as hinted at by Ibn Sina in the book al-Isharat wa al-Tanbihat (Sina, 1375), when explaining God's knowledge of Himself and creation.His knowledge of causes and effects Then Poporius' view was shared by other Peripatetic philosophers, including medieval Muslim philosophers such as al-Farabi and Ibn Sina, but at the same time he rejected this idea and considered it a false idea (fasid) when referring to human knowledge about objects.external (Razi, 1411).
It was only Mulla Sadra who carried out a detailed discussion and expanded this concept not only in relation to God's knowledge but also in relation to all forms of human knowledge.Mulla Sadra, in his book Al-Hikmah al-Muta'ali, apart from using the term Ittihad al-'aqil wa al-ma'qul, sometimes also uses the term Ittihad al-mudrik wa al-mudrak or Ittihad al-'alim wa alma'lum.
In initiating the KSO principle, Mulla Sadra began his discussion on the division of knowledge into two, namely husuli (conceptual/correspondence) science and huduri (presentational) science, and distinguishing the meaning of 'unity' (Ittihad).The following is a brief explanation of these two things, followed by an exposition of the KSO principles.

Division of Knowledge: Husuli (conceptual/correspondent) and Huduri (presentational)
First The science of Husuli.Husuli science is science or knowledge obtained based on the correspondence process that occurs between the subject and external objects.Between the two, there is an independent existence that is different and unrelated to each other.Both have specific dimensions and degrees of existence and are independent of each other, or we can say that there is no causal relationship between the two.The non-binding of these two existences covers all things both ontological, epistemological, and logical so that it is rationally impossible for the two objects to become a unity because if not, there will be inqilab (change with the elimination of the existence and identity of one to another).This is clearly not perhaps, as Mulla Sadra stated: "... nor is the acquisition of forms of perception for the subject and witness of the perception process like the arrival of the form of the universe in its external dimension."(Razi 1411) In another part, Mulla Sadra also explains: "Knowledge is a visual image that results from something in the subject's self."(Razi, 1411).
Science in this sense is a correspondence between subjects and external objects.It is the subject who carries out the perception process, giving rise to a correspondence between the two.Allamah Thabathabai explains the science of Husuli as follows: We say: As has been discussed in the discussion of Mental Existence: That in fact we have knowledge of external issues which are outside ourselves, meaning they are conveyed and present to us in the form of accidents and not external existence which has effects, this part of knowledge is called Correspondence Science (Thabathabai, 1415).
Allamah Thabathabai stated that in this correspondence the object absorbed by the subject is a visualization of the Entity of the objective object as an external existence because it is impossible that what is absorbed and enters the subject's mental state is an external existence because external existence has an effect that only occurs in the external dimension and does not occur in the mental dimension.Thus, what is absorbed by the subject is not the external existence of the object but the visual form of the object entity.This is the meaning of Correspondence Science.
Second, Huduri (Presentational/Presence), In contrast to correspondence science, what is present in the mental subject is the visual form of the object entity, but in Presence Science, what is present in the mental subject is the existence of the object.
From the simple definition and description above, we can substantially differentiate between Huduri science and Correspondence Science, some of the main characteristics of Huduri Science include that: 1.It is existentially present within the Subject.2. is not a conception formed from syllogisms that occur in the mental.3. freedom from the dualism of truth and error.
These three main characteristics occur because there is no longer a separation between external and internal objects.Let's take the example of the pain we suffer, epistemologically first, we know that this pain is existentially present in our mental state and we can never find it in its external existence.Second, pain is not formed based on several propositions that we negate each other to form pain. Third, because of its existential presence, judgments of right and wrong no longer occur as occurs in Correspondence when we negate mental objects and external objects.Allamah Thabathabai describes the Science of Huduri as follows: "From the part of knowledge: A form of knowledge in us (is present) with its essence which is denoted by (I) because in fact it (I) never disappears from us under any circumstances; whether alone or busy, asleep or awake, or in any other state.And this is not the accidental presence of essence (I) in us in the form of the presence of understanding from the science of correspondence: because the understanding that is present in the mental, however we describe it, will not be separated from its relationship with the plural and identified in external existence, and this is what we witness from ourselves what we call (I) is an identity which is essentially uncomposed and identified in the dimensions of existence, then we have knowledge of our essence (I) and present ourselves with an external existence which is the basis of identity which has the following effects: and this is another kind of knowledge called Huduri " (Thabathabai, 1415).
I am of course a mental existence that exists in every self, its presence is not only entity but clear existentially, therefore the objective object is not something that is outside the subject's objective self, it is present and is an inseparable part of us.Because of their existential presence, of course there is no correspondence that separates the two.Mulla Sadra specifically explains this existential presence: "…Existence cannot possibly be perceived through its accidents except based on its existential selfhood and not from its mental imagination.If we imagine this existence in our minds, there is no doubt for us that we know based on its essence, knowing in this context does not require argument."(Sadra 1410).
For Mulla Sadra awareness of Me is the most basic awareness that all humans have and is clear without the need for a thought process.In a context like this, we have the clearest presence in ourselves because, as mentioned above, the presence of the object (I) is no longer something foreign and separate from the subject's self.
Although based on the characteristics between Husuli science and Huduri science we find fundamental differences, but substantially according to the Hikmah Muta'aliyah philosophers , Husuli science as knowledge obtained based on the process of correspondence with external objects in principle goes back to and originates from Huduri science , because the knowledge that exists produced in the subject is the form of an object that is present in the subject's mind, its presence in the mental realm is nothing other than in the form of mental existence, so that the subject's perception of the incoming object is a perception of mental existence and this is the meaning of the science of Huduri .As stated by Allamah Thabathabai: Then, the production of knowledge in ourselves means: the arrival of an object in us, because knowledge is the substantive identity of the object, whereas we do not mean by knowledge except the production of an object in ourselves and the result or presence of the object is nothing other than in its existence and that existence is itself (Thabathabai, 1415).
The object that is present in the subject is a visual that is created mentally as a mental existence from external existence and of course the presence that occurs in the subject is an existential presence so that the subject's perception is not of external existence but of the mental existence that is present.
Based on the picture above we can state that the Science of Husuli in principle goes back to and originates from the Science of Huduri, because when visual external entities enter the soul of the subject, the soul carries out the process of creating the mental existence of the object.For this Mulla Sadra and his followers put forward the following arguments (Yazdi, 1409): First, External objects are external existence, perception through the correspondence process conveys to the subject the visual form of the object.Visual form is not the substance of the object because the substance is its existence.If the subject's knowledge of the object is based on the visual form of the entity that is present while the form of the object entity is not the object itself, then the subject has no knowledge of the external object, this will lead to skepticism.
Second, External objects are bound to space and time and experience a process of change with the passage of time, however, mental objects which are a scientific form of external objects do not depend on space and time and are permanent, so whenever and wherever the subject wants their presence, the mental object will be present on the subject.This proves that the object that is present in the subject is a mental existence of the external existence of the object.
Third, From the mental form present in the subject, the subject can make changes to form a new type of existence even though the external object remains in its original condition.If mental objects are tied to external objects, of course no changes can occur according to the conditions of the external object.
Fourt, External objects have specific effects such as the vast sky, the great earth, the boundless ark, the high mountains.In the process of Husuli it is of course impossible to perceive the form as an external existence and if what is perceived by the mind is only a visual entity, then we return to the first argument.Therefore, the soul exactly that creates mental existence from this external existence.
Fifth, The mental can make distinctions between accidents and the substances contained in mental objects.For example, the mental can separate the blue color of the sky from the external object blue sky which is impossible to separate between the accident and the substance.

Mulla Sadra in this connection states:
In fact, a large material visual form will not be produced on small matter, it is not possible for a mountain to enter through dust particles, nor can an ocean enter a pool, this kind of thing contradicts the existence of perception because the receptivity of the soul is the same between the big and the small.The soul has the ability to present to its imagination visuals from the sky and the earth and anything between the two in an instant without losing any of it as described by our leader and leader Muhammad Saw.: 'Truly the heart of a believer is bigger than the Throne' and just like what Abu Yazid Bustami said in telling himself 'If only the Throne and others were in the corner between the corners of Abu Yazid's heart it would not be felt for him' .And the reason for all that is because the soul does not have a measure and a place for it, otherwise it must be limited to certain limits and a specific place so that it is not receptive to anything else except to increase its breadth or subtract something from it and there remains for it something that is not something that is perceived for it or remains in that soul something that is not an observer for him so that something is known and unknown or that knows and that does not know at the same time and this is not possible based on arguments or thoughts.Because we actually know that the soul of ourselves is one identity if we perceive something that is large, perceive the whole without exception and not just a part because there is no part for it due to its simplicity (Sadra, 1410).Mulla Sadra's argument provides evidence for the existence of the mental and also shows that the knowledge that exists within us is the knowledge of Huduri.The science of Husuli functions only as a cause for the soul to carry out its creativity in realizing the mental existence of external objects.

Sorting out the meaning of Ittihad (Unity)
The term unity (Ittihad) related to this principle has a different meaning and emphasis from what was understood and claimed by previous philosophers, especially by Peripatetic philosophers who rejected the possibility of subject-object unity in all forms of human knowledge.Therefore, Mulla Sadra sorted out several meanings of unity and determined the type of meaning intended in this principle.However, before that, it is necessary to mention the meaning of unity according to the Taqi Mishbah Yazdi as additional information about variations in the meaning of unity or Ittihad, including (Yazdi, 1409): First, Accidental Unity with Substances which have the nature of dependence on each other which externally cannot be separated.Like between chalk and white.Second, The unity of Form and Matter that cannot be separated from each other externally.Because every material must have a form.Third, The unity of several materials in one form, such as the unity that occurs in the form of water which is formed from several types of matter (H 2 0).Fourt, The unity between Cause and Effect is known in Al-Hikmah Muta'aliyah terms as Ittihad Tashkikiyyat (Unity of Graduality).Fifth, Unity between several effects due to a cause that cannot possibly be separated between these effects.
The variations in the meaning of unity mentioned above are not unity as intended by Mulla Sadra.Mulla Sadra himself divides the types of existential Ittihad into three basic parts: "…In fact, unity is described in three forms: First, there is a unification of one existence into another existence, that is, there is a unification of two existences of something into one form of existence.This is a clear impossibility which has been explained by Shaykh (Ibn Sina)

in his argument against unity (Ittihad al-'Aqil wa al-ma'qul). Second, the merging of several perceptions or several entities into one definition or another entity which changes from its initial identity or entity so that it makes itself (which is really) it in the first substantial negation. Even this is clearly impossible, because it is impossible for a definition to become another definition or one meaning to become another meaning, just as it is impossible for a definition of a Subject to become a definition of an Object. It is possible that a simple existence can fall into the Subject category with
the intention of being an Object that is one existence but has a different meaning that does not lead to a plurality of existential dimensions.Third, existential change is based on the inclusion in the category of definitions of reason and general entities after previously not being able to be categorized into them.But furthermore, because the process of perfection occurs in its existence, this is not impossible and even happens factually.Like the overall meaning of categories found in different forms such as; Hard matter, plants and animals are all present and composed in one human form."(Sadra, 1410).
Mulla Sadra shows in the second form of Ittihad (Unity) that the plural form of definition for one existence, the meaning of Ittihad referred to in the concept Ittihad al-Aqil wa al-Ma'qul can be categorized and what Ibn Sina feared in this type of unitary form would not happen.However, according to Hasan Zodeh Amuli, although Mulla Sadra hints at the possibility of Ittihad in the second type, the actual category that Mulla Sadra refers to is the meaning of Ittihad is of the third type.This is because Ittihad in the third type is related to the process of perfection and also this occurs through substantial movement.Science is nothing but part of the process of human perfection.With this basis, according to Amuli Ittihad means "changes in existential quality in the process of perfection after the introduction of various definitions" (Amuli, 1375).

Ittihad al-'Aqil wa al-Ma'qul (Kemenyatuan Subjek-Objek)
Based on the explanation of knowledge and its division above, it can be concluded that the knowledge that humans have is essentially the result of perception or perception of mental existence and its qualities, and this shows that between subject and object there is a close and inseparable correlation.This is not only limited to the perception of I (the subject itself) or the imagination that we create but also to all objects that we perceive.If scientific concepts like this previously only occurred in God's knowledge about himself, for Mulla Sadra this also applies to human knowledge and includes all perceptions that occur.
Mulla Sadra explains that between the subject and the object of knowledge, whether based on the process of conception, perception or sensing, they become one unit that is not dimensionally different except based only on the point of view of seeing the functional position (i'tibar), because it is not rationally objective that the object is existentially present for something other than the subject.This concept of unity between subject ('aqil), object (ma'qul) and reason (aql), is what is called Ittihad al-'aqil wa al-ma'qul that the subject carries out the process of perceiving existence with the object as the perceived and the subject-object correlation that embodies knowledge, a simple existential unity occurs.As has been discussed in the science of huduri, the objective object that enters the subject in the form of a visual entity from external existence enters the subject's soul and then the soul carries out its creativity to create a mental existence from the visual object that enters.This mental existence is not something separate from the mental subject because existence is one thing.
Existence in Mulla Sadra's view is one thing in different graduality.This unity is essential unity because in Mulla Sadra's philosophy existence is an essential substance.The unity that occurs between the subject, object and the relationship between them is an existential unity, not a unity as some Peripatetic philosophers mistakenly view this form of unity.
As mentioned in the previous sub-chapter, the unity meant by Mulla Sadra is unity in simple existence (Basiṭ al-hakiki) which is not composed of various independent elements that form unity.In a context like this, knowledge is essentially not something separate from the subject.Because knowledge other than Kayf al-Nafsani (Quality of Soul) is also part of Jawhar (Substance).The quality of knowledge that develops in the subject's soul will at the same time develop and improve the quality of the subject's own soul.The soul, because it is an entity substance for existence, may automatically increase the quality that occurs in the soul will influence the quality of the subject's existence and even bring the subject to the realm of malakut as part of the level of human perfection (Sadra, 1410).In another passage Mulla Sadra states: "Knowledge is the seed of witnessing."(Sadra, 1410).This epistemological concept is clearly an argument for the belief of Sufism experts in science and this is also the meaning of the Prophet's words "Knowledge is light in the soul".Sadruddin Qunawi, Ibn Arabi's most important commentator in his book Risalat al-Nushush states: "Know that in fact the highest degree of knowledge of something, whatever it is in relation to the owner of any knowledge ('alim), whether a single or plural object, is that which results from unity with the object ( Ittihad al-'alim wa al-ma'lum )" (Qunawi, 1362).
This is what Mulla Sadra meant by Ittihad al-Âqil wa al-ma'qul.Mulla Sadra has perfectly placed his epistemological concept into a synthesis between Peripatetic, Illumination and Sufism epistemology, as well as providing rational explanations and arguments in the debate about the Knowledge of God in theological discourse.

Realism
There is no doubt that Mulla Sadra was a realist philosopher.In all his philosophical buildings, he has initiated brilliant ideas that synthesize various previous philosophical thoughts in order to confirm his belief in the principle of reality outside the subject (Ashl al-Waqi').For example, at its simplest, Sadra shows his realist attitude when he understands that universal quiddity [concepts] are not reality itself but are only reflections or narratives (hikayat) of external objects or realities (waqi'iyat kharijiyah) and in fact these concepts are abstracted by reason from them (Sadra, 1410).It shows that belief in external reality is fundamental, because whatever the mind perceives and understands about something in the external world is based on the belief that something really exists and is the source of its perception.And there are many other explanations from Mulla Sadra that show this attitude.
However, the style of realism promoted by Mulla Sadra, according to the author, is a unique style, not only different from what was proposed by previous realist philosophers such as Aristotelian realism, but also modern realism.Among those that can show the uniqueness of realism thinking is the principle of subject-object unity of knowledge which shows the idea of realism by solving epistemic or perceptual problems, namely the problem of the relationship between consciousness and external reality or between subject and object; a problem that requires decisions both epistemologically and ontologically, namely the possibility of the subject being able to know objects or external realities as they are and the confirmation of their independent existence in the external world.This principle provides a solution to a very fundamental problem and has become a polemic even today by proposing several considerations, as follows:

Elimination of the Gap between Subject and Object
One of the crucial issues in human knowledge is the value of truth, in fact it is the most important thing because it is the essential goal of the activity of knowing.Apart from that, the truth value is an absolute requirement to ensure the ontological status of external objects as they are in accordance with the subject's perception.However, in the process of knowing this goal is not easy to achieve, because the subject is separated from the object and is only connected by concepts or sense data.Errors often occur due to incompatibility or non-correspondence between concepts and sensory data and the object itself.The accuracy of knowledge about objects is largely determined by these concepts and sensory data.So, concepts and sensory data have created a gap between subject and object, so that objects are not known or present directly, but through the intermediary of concepts and sensory data.
To overcome this problem, there is no other way except to eliminate this gap.Mulla Sadra believes that in true knowledge, the object must be presented directly so that there is no gap between the subject and the object.The object that is present is certainly not an external-material object, but a subjective object that arises from the soul or mentality itself with adequate power of disclosure.In this case Sadra differentiates objects (ma'lum) into two, namely external-material objects as accidental objects (ma'lum bi al-'aradh) which are indirect objects and function as a stimulus for the soul to give rise to direct objects, and objects internal/subjective (ma'lum bi al-dhat), namely the direct object resulting from the revelation of the soul and emerging (qiyam shuduri) from it.
With this understanding, according to Mulla Sadra, the subject is one with the object, because between the two there is no gap that separates them, so that external reality can be ascertained of its ontological status as it is and occurs in the Huduri process.This does not mean that Sadra does not accommodate correspondence knowledge, but he believes that all knowledge occurs in the Huduri process, because even the correspondence process (Husuli) is only the beginning for knowledge of external-material reality which will culminate in the Huduri process.This is also confirmed by Thabathabai who stated that correspondence knowledge ('ilm Husuli) will return to presentational knowledge ('ilm Huduri).

Knowledge is the Object Itself
As is generally known, the status of 'knowing' reality as it is for the subject is a condition where the subject is able to present it identically in his mind, because if this is not the case then the subject will bear two predicates, namely not knowing and/or being mistaken in his knowledge.Confirming this, in Mulla Sadra's epistemology, identity or correspondence between knowledge and the object is an absolute condition for the subject to be called 'knowing'.
The activity of knowing is an effort to present an object in the subject's mind or mentality.
The next problem is what are the criteria for saying that knowledge is the presence of an object in the mind, so that the subject can be considered to truly know reality?Mulla Sadra resolved the above problem with the principle of subjectobject unity which is correlated with his other philosophical principles.Based on this principle, apart from the obliteration of the gap between subject-object, what he calls in the process of knowing also occurs the identification ('ainiyat) of knowledge with the object itself.Sadra believes that in true knowledge, namely the revelation of the essence of the object by the subject, knowledge is identical to the object or knowledge is essentially the object itself (al-'ilm huwa 'ain al-ma'lum), as mentioned in the sub-chapter previous.
Departing from the explanation above, we can see knowledge in two aspects, namely as the result of the process of knowing or knowledge and as the object of knowledge itself.In the sense that one entity has two faces or points of view, namely knowledge and the object itself.Thabathabai states that our knowledge about something means the presence or manifestation of that thing (object) in our self or mental state, therefore knowledge is the object itself (alma'lum bi al-dhat) (Thabathabai 1415).
This can be emphasized considering that the meaning of knowing is the presence of an object through the process of perception for the subject, so the presence of an object is nothing other than the existence of the object itself.Therefore, it is not wrong to say that knowledge is not something different from objects, in fact objects are knowledge itself in its essence and existence.True knowledge of reality is not just a shadow or image without meaning and existence, but the object itself and its essence.Mutahari in the sharah of the Mandzumah book, emphasizes that objects manifest with mental form and they occupy mental form.Meanwhile, knowledge is the nature of [objects] for the mental and is another dimension of the object itself when it manifests in the mental (Muthahari, 2003).
However, knowledge which is the object itself when manifested in the subject's mind is certainly not like the existence of an external object in terms of its effects.Knowledge or objects manifest with mental form (wujud dhihni) so that their effects adapt to the character of their existence.Objects that are present in the mind are essential objects or objects that are known directly to the mind, while external objects are objects that are accidental because they are not present directly in the mind.Therefore, in Shadrian's epistemological system, objects of knowledge are divided into external-accidental objects (alma'lum bi al-'Aradh) and internal-essential objects (al-ma'lum bi al-dhat) (Yazdi, 1992).
At first glance, Shadrian's realism seems to affirm modern realism, namely RL, especially Naive Realism by starting from the issue of perception.However, of course, Shadrian's realism is not the same as RL, even though they both assume that the mental is capable of perceiving external objects as they really are.Shadrian's theory of perception, as already mentioned, affirms two forms of knowledge, namely correspondence (Husuli) and presentation/presence (Huduri) and knowledge or objects that are present in the mind are not just concepts produced in correspondence but rather direct presentations (hudur) because the mind creates them (qiyam shuduri) thanks to the process of purification and perfection , because knowledge in the form of the meaning or essence of immaterial objects cannot possibly be perceived directly by the mind from material objects in the external realm through the sensing process; Sensing only captures the material qualities or appearance of objects .Therefore, knowledge or internal objects are not mere concepts or physical appearances of objects as RL claims, but rather the object itself is in the form of essence (mahiyyah) and its own form in mental form obtained through a presentational process (Huduri).Conceptual or correspondence processes still play a role in Shadrian's epistemological system, but only as a stimulus for the subject to directly reveal the actual object or reality.

Subject-Object Unity is Existential Unity
The schools of modern realism presented by RL and RTL have attempted to put forward views in order to maintain beliefs about the existence of an independent external reality by first solving the problem of perception that the subject has the ability to know that reality as it is.As mentioned in the previous sub-chapter, RL believes that perception is awareness resulting from the subject's direct contact with the object.This means that perception is the object itself and its physical properties and qualities, not the result of mental interpretation of it.Like one of its subsidiary schools, naive realism, claims that the subject's mind is like a mirror that is able to capture all aspects of external objects as they are, including their physical qualities such as taste, smell, shape, etc. as far as sensory experience goes.While RTL believes that perception is only a representation of external objects, what the subject's knowledge about the object is actually in the form of sensory data about the object.From the explanation above, both RL and RTL along with other schools of realism try to emphasize beliefs about actual reality by both relying on sensory experience as an instrument of perception which becomes a form of the subject's awareness of the object, although RL then considers it to be a reflection of what the object is, whereas RTL considers it to be just a representation through which the subject knows the object.Thus, the two major schools of modern realism have a point of contact in that the presence of external objects in the subject's mind is only limited to quiddity (mahiyyah), in fact only in the form of accidental qualities, not substantial, because it is known that sensory experience is never able to present the essence of the object.in the form of its substance but only its accidental properties.In short, the objects present to the subject in the view of modern realism are only accidental properties, not the essence of the object itself.So even if we call it the unity of object and subject in the discourse of perception, then modern realism only shows the unification of the accidental quiddity of object and subject.This is different from what was proposed by Mulla Sadra in answering the problem of the subject's mental perception of the nature of external objects.With the principle of subject-object unity (Ittihad al-'Aqil wa al-ma'qul) which is supported by the principle of mental existence (al-wujud al-dhihni) and knowledge of presence (al-'ilm al-Huduri), he believes that the essence of External objects can be known mentally, as previously explained, because in perceptual activity, the subject is able to directly present the object so that a union occurs between the two.Furthermore, Sadra emphasized that this unification is not limited to the essential unification of the quiddity of the object with the existence of the subject, but rather the existential unification between the existence of the object and the existence of the subject.Of course, what is meant by the existential union of subject-object here is not the union between the existence of the subject and the existence of external objects, but between the existence of the subject and the existence of subjective internal objects (al-ma'lum bi al-dhat) (Thabathabai, 1415), as previously mentioned regarding the object of knowledge in Shadrian's epistemology.
According to Mulla Sadra, knowledge of a subject is not just an effort to present the quiddity of an object in the subject's mind, but also its existence.The object here is not an external-material object (al-ma'lum bi al -'ard) certainly, but rather an internal-subjective object that has an identity with an external-material object.This is possible, according to Sadra, because the actual presence of the object is direct (hudur) and upright with mental existence (wujud dhihni).At this point, the subject's mental or soul experiences unification with the object in the sense that the subject's existence becomes increasingly expanded and perfected, not in the sense of becoming another reality.As for external-material objects, the subject still has a relationship with them in the pursuit of correspondence knowledge (al-'ilm al-Husuli), but this relationship is secondary and a stimulus to help the subject to present the internal-subjective object directly (Huduri).From the explanation above, it is clear that the presence of an object for the subject is the presence of quiddity or essence as well as its existence which is internal-immaterial and shows the unity between the subject and the object, so that the subject's knowledge of the nature of the object is essential and direct knowledge without the representation of sensory data.This is what emphasizes Shadrian's form of realism as a more original form of realism than other modern realisms, especially those that developed in the West, with belief in external reality which is supported by a more convincing perception of it without room for doubt and error.

Conclution
From the description above regarding the understanding of realism, starting from the issue of perception, several things can be concluded, including: The problem of the subject-object dichotomy and the relationship between subject consciousness and external objects that is attempted to be resolved by the schools of modern realism that are presented by two major schools, namely direct realism and indirect realism, is still considered inadequate because the current school is only limited to revealing the accidental qualities of objects that are believed to be a reflection of objective reality and still allows for a distance that separates subject and object, so that the possibility of doubt regarding perception still continues to haunt.Thus, the realism promoted by the schools of modern realism, which departs from the discourse of perception, still leaves a mysterious part for knowledge about the nature of reality.
The presence of Mulla Sadra's philosophy with its various philosophical ideas, especially the principle of Ittihad al-'Aqil wa al-ma'qul (subject-object unity), according to the author, can answer the question of the nature of reality by resolving the above problem of dichotomy and the relationship between subject and object consciousness.This belief is confirmed by the principle of Ittihad al-'Aqil wa al-ma'qul, which has several features that provide a solution to the epistemic problem above, including: (a).Elimination of the gap between subject and object because the object's knowledge is directly present (Huduri) to the subject (b) Objects that are directly present are internal-immaterial objects and are essential for the subject (al-ma'lum bi al-dhat), not just sensory data from external-material objects, which is also perception or knowledge (' aql /' ilm) itself, and (c).The object that is directly present (Huduri) and united with the subject is reality itself in the form of the essence of the object as well as its mental existence, not just quiddity in the form of material qualities.Based on this, the principle of Ittihad al-'Aqil wa al-Ma'qul emphasizes Sadrian's style of realism by starting to explain the issue of perception as a more comprehensive and original realism.