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Contemporary Philosophy

Heidegger's Reading of Descartes' Dualism: The Relation of Subject and Object

A. Kadir Çüçen
Uludag University

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ABSTRACT: The problem of traditional epistemology is the relation of subject to external world. The distinction between subject and object makes possible the distinction between the knower and what is known. Starting with Descartes, the subject is a thinking thing that is not extended, and the object is an extended thing which does not think. Heidegger rejects this distinction between subject and object by arguing that there is no subject distinct from the external world of things because Dasein is essentially Being-in-the-world. Heidegger challenges the Cartesian legacy in epistemology in two ways. First, there is the modern tendency toward subjectivism and individualism that started with Descartes' discovery of the 'cogito.' Second, there is the technological orientation of the modern world that originated in the Cartesian understanding of the mathematical and external physical world.

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Descartes stands at the beginning of modern philosophy and Heidegger accepts Descartes' role in the history of metaphysics. Descartes is the first thinker who discovers the "cogito sum" as an indubitable and the most certain foundation and thereby liberates philosophy from theology. He is the first subjectivistic thinker in the modern philosophy and he grounds his subjectivity on his epistemology.

The orientation of the philosophical problems with Descartes starts from the "ego" (the "subject") because in the modern philosophy the "subject" is given to the knower first and as the only certain thing, i.e., the only "subject" is accessible immediately and certainly. For Descartes, the "subject" (the "ego", the "I", "res cogitans") is something that thinks, i.e., something that represents, perceives, judges, agrees, disagrees, loves, hates, strives, and likes. "Descartes calls all these modes of behavior cogitationes." (1) Therefore, "ego" is something that has these cogitationes. However, the cogitationes always belongs to the "I", I judge, I represent, etc. Heidegger maintains that Descartes' definition of "res cogitans" says to us that "res cogitans" is a res whose realities are representations. (2)

The subject of cogito is beyond doubt if one asks what this subject is. Descartes cannot answer, because, if the subject is embodied in the world, the subject becomes a worldly thing in which man's doubts begin. Therefore, for Descartes, the subject is simply the "I", "soul", or the "thinking substance" which is what it is even without the body and the world. Another difficulty in the method of radical doubt is the object of thinking. What do I think? Descartes answers that I think my own thoughts. For him, I know my own cognitive images even if I may not know the worldly thing because I have the idea of the worldly thing in my cogito, and therefore cogito with its contents is beyond doubt.

According to Descartes, "res cogitans" also means "cogitat se cogitare". (3) The "ego" as subject has its predicates in a cognizing way; so I know about the predicates I have, i.e., I know myself. Heidegger thinks that Descartes' understanding of subjectivity is connected with the hupokaimenon in which the subject is present or the extant. In ancient ontologies, being is understood as being-extant, lying present-there, and substance, which are corporeal things and mental things. Therefore, Descartes did what the traditional ontologies developed as beings extant.

The basic idea of traditional epistemology lies in the argument for skepticism about the existence of the external world. The Cartesian legacy carries the traditional epistemology through the entirety of modern philosophy. The problem of traditional epistemology is the relation of the subject to the external world. There are two kinds of subject-object relationships: Firstly, the subject orients itself towards the object, i.e., the subject knows the object. Secondly, the object is out there as the reality of the external world, and the subject tries to know what it is which is out there. The consequence of the spirit of Descartes' philosophy separates the ideal inner world of subject from the outer world of the object. The subject is divorced from the world and the world is put out "there" as separate from the subject. Heidegger challenges this Cartesian legacy in epistemology in two ways: Firstly, there is the modern tendency towards subjectivism and individualism started with Descartes' discovery of the "cogito". Secondly, there is the technological orientation of the modern world which has been originated by the Cartesian understanding of the mathematical and physical external world. (4)

Starting with Descartes, the subject becomes the center, and the subject, as the first true being, has priority over all other beings. Contrary to this priority of the subject, Heidegger's goal is to show that there is no subject distinct from the external world of things, because Dasein is essentially Being-in-the-world. Therefore, Heidegger puts together the separation of the subject and the object by the concept of "Dasein" which is essentially a Being-in-the-world. However, Being-in-the-world does not mean that it is like a piece of chalk in the chalk box. Being-in, as the most essential and existential characteristics of Dasein, signifies the expression of such terms as "dwelling," "being familiar with," and "being present to."

The distinction between the subject and the object makes the possibility of the distinction between the knower and what he knows. Starting with Descartes, the subject is a thinking thing, which is not extended, and the object is an extended thing, which does not think. Heidegger rejects this distinction of subject-object in his existential analytic of Dasein as Being-in-the-world. He takes Dasein as the starting point because only Dasein is the Being who is aware of himself, of the world, and of Being, Dasein is the only Being which can gain access to this problem. Dasein is always aware of itself as being in a world. Dasein, which raises the question of Being, must be disclosed in its Being because it is distinct from other beings. Therefore, unlike the idea that man can be understood in terms of the concept "res extensa", i.e., in terms of its physical and mechanistic dimensions in the Cartesian model, Heidegger tries to shift the idea of subject from the Cartesian mechanistic interpretation of man to its more primordial sense of Being. In this manner, Heidegger takes over Husserl's orientation toward the question of origin and in his existential analytic of Dasein, Heidegger no longer grasps the Being of Dasein as something present-at-hand.

Heidegger criticizes the Cartesian tendency to take "knowing" as our primary way of interacting with things, because the problem arises of how this knowing subject comes out of its inner sphere into one which is "other and external." In response to this traditional dilemma of subject as knower and object as known, Heidegger suggests that "knowing" is a founded mode of Being-in-the-world. (5) Since Descartes and above all in German idealism, the fundamental problem of ontology is that "the ontological constitution of person, the ego, the subject is determined by way of self-consciousness." (6) For Heidegger, to accept self-consciousness as the dominant element of the subject is not sufficient to determine the self-understanding of the subject because "self-understanding is always determined by way of the Dasein's mode of being, by way of the authenticity and inauthenticity of existence." (7) Therefore, instead of self-consciousness, the mode of existence defines self-understanding of Dasein. Contrary to the idea of modern philosophy that the ground can be found in an unconditioned subjectivity, Heidegger maintains that the self or the subject is an understanding determined by mood, but not pure consciousness; consequently, with the point of departure from pure consciousness stemming from Descartes dualism, the self or subject is in the Dasein's factical existence, in the unity of thrownness and projection, and in moodiness and understanding.

Heidegger rejects the traditional theory of knowledge, which is generally based on the distinction between subject and object. Since "knowing has the phenomenal character of a Being which is in and towards the world", (8) knowing is already alongside its world, i.e., knowing is grounded beforehand in a Being-already-alongside-the-world, but this cannot be a starting point at something that is present-at-hand because "Being-in-the world, as concern, is fascinated by the world with which it is concerned." (9)

furthermore, Heidegger investigates "knowing" in terms of its ontological basis. For this reason, Heidegger denies the Kantian logical description of the possibility of knowledge and rejects the scientific explanation of things as present-at-hand. Heidegger sees Descartes' epistemology behind modern thoughts. Modern thoughts on the term of "knowing" are basically theoretical and are the derived form from ready-to-hand. Heidegger thinks that we must go beyond the knowledge of present-at-hand and that we just reach the primordial knowledge of things present-at-hand which is ready-at-hand. Therefore, he tries to reveal a pre-understanding of present-at-hand. His thought is somehow an anti-modern idea. The term knowing, for Heidegger, is knowing one self, knowing its existence, knowing its own Being. Knowing is an ontological realization of one's own Being because Dasein essentially comports itself toward its own Being. Dasein's self comporting toward its own Being distinguishes Dasein from everything else. It is distinctly a way of Being ontologically from the traditional subject as present-at-hand. For this reason, according to Heidegger, critical philosophy in modern times (such as the Kantian philosophy) is uncritical and dogmatic because, in beginning with the problem of knowledge, "the question of the kind of Being which belongs to the knowing subject is left entirely unasked." (10)

For Descartes, the subject is to be understood as a res cogitans, a thinking substance. Heidegger rejects this Cartesian understanding of the subject as a substance. Contrary to the interpretation of Pure-I or pure subject, Heidegger maintains that Dasein as Being-in-the-world is no longer a distinction between a subject and a set of objects which are to be known, but it is a relation because Dasein is always involved in a world, the definition of Dasein as a relation becomes concrete only as "Being-in-the-world." "Dasein expresses itself as Being-in-the-world." (11) However, this does not mean that I or the subject has itself in view as being-in-the-world in the everyday manner because "the everyday interpretation of the self... has a tendency to understand itself in terms of the world with which it is concerned." (12) In other words, whenever Dasein sees itself ontically, it fails to understand itself in relation to the kind of Being of that entity which it is itself as Being-in-the-world. (13) For this reason, Heidegger tries to overcome the Cartesian distinction between the subject and the object by defining the essence of Dasein as "existence" and "in each case mine" Being-in-the-world.

According to Heidegger, I or the subject has its meaning in "Being-already-in-the-world and in "Being-alongside-the-ready-to-hand-within-the-world" because I or the subject must be understood in terms of our authentic potentiality-for-Being; so, the subject is the basis of care and selfhood is possible in the authenticity of Dasein's Being as Care. (14) Heidegger defines the subject or subjectum (in the traditional sense) in terms of care and authentic potentiality-for-Being. This definition of the subject has the primordial, existential. and ontological basis for the question of the subject and its distinction from its object.

Who am "I"? For Heidegger, this can be answered in the question of Dasein's who. Primarily and for the most part Dasein is not in itself; it is lost in the theyness or in the average everydayness in which it is inauthentic. However, when Heidegger asserts that Dasein's essence lies in its existence, he means that I-hood and selfhood must be conceived existentially. (15) In other words, I-hood and selfhood must be understood existentially and ontologically rather than existentielly and ontically in its own Being as Being-in-the-world. Furthermore, if "I" is understood as a logical subject or res cogitans or a representation or a substance, then "I" means something always present-at-hand. If "I think something" is conceived as a basic characteristic of the self, then "I think something" is not enough ontologically as a starting point because "something" remains indefinite and "something" is conceived as an entity within-the-world. Therefore, for Heidegger, "I think" or "Cogito sum" remains as an isolated subject. (16)

The "I" that Descartes discovers through his methodological doubt is by no means the most primordial self. Heidegger suggests that Dasein as being-in-the-world solves the dichotomy of the subject-object ontology. The subject-object picture of our ordinary existence predicament appears as a derivative mode as Being-in-the world. If the dualism of subject and object is a derivative mode, then it cannot be a primordial mode of the Being of Dasein. In this sense, a dualistic picture of the Cartesian understanding of Being cannot provide an ontological foundation to the meaning of Being. Therefore, the Cartesian legacy can be destroyed in terms of the reinterpretation of subjectivity and its correlative understanding of the external world. (17)

The basic concept of every philosophy lies in an idea of how the knower relates himself to the things known. This leads to a distinction between realism and idealism throughout the entire history of western philosophy. However, Heidegger's phenomenology is deliberately neither realistic nor idealistic. His phenomenology has a place in history lying beyond the traditional metaphysical opposition of realism and idealism. Heidegger's task of phenomenology tries to overcome the traditional metaphysics since Plato's time.

For Husserl, phenomenology was the description of the events occurring in the world in so far as a subject was aware of them; his technique was to reduce the world to phenomena as they occurred to a consciousness and to use language to describe what appear in this way to the attentive consciousness. For Heidegger, there is no distinction between consciousness and body given any degree of apodictic certainty. Interpreting is a way of understanding what is given in our preontological understanding of our own being. The phenomenon we are interested in revealing must be disclosed in our act of discoursing upon our relationship with our worlds. (18)

Heidegger reverses the "cogito Sum" with "I am in the world", i.e., Dasein's Being-in-the-world. He rejects the dichotomy of the subject and object in the Being of Dasein as Being-in-the-world. He interprets dualistic modern ontology in the concept of Dasein's Being-in-the-world. Therefore, for Heidegger, "I am in the world" precedes the "cogito sum." Heidegger raises a new question of the meaning of Being primarily in his "Being and Time", "The Basic Problem of Phenomenology", and his other writings. Heidegger destroys phenomenologically the history of ontology in terms of his understanding of the Temporality of Being, and he reformulates the question of the meaning of Being, i.e., Dasein phenomenologically, temporally, hermeneutically, and existentially.

The relationship between the subject and the object is interpreted as Bild, as view, as picture. This relation dissimulates the truth as unconcealment. Therefore, Heidegger's destruction of the "cogito" is the destruction of the age to which it belongs. The "I am" is forgotten in Descartes' philosophy. It has to be unconcealed from its ontological roots. In this sense, the retrieval of the "cogito" is possible only in an hermeneutical description of the "I am" which mean Being-in-the-world. Ricoeur concludes his critique of Heidegger's destruction of Descartes' understanding of "cogito sum" that the destruction of the 'cogito' as an absolute subject is the reversal of an hermeneutics of the "I am" as constituted by its relation to Being. (19)

In the critique of the subject-object relation, Heidegger's aim is to deny the priority of the "cogito' "over the "res extensa". In his denial, Heidegger rejects the Cartesian understanding of the notion of the "ego" or of the "self", or of the "cogito" as a mere epistemological principle. Contrary to Descartes' "cogito", Heidegger tries to support a ground to the "I am" instead of the "cogito". Paul Ricoeur calls this an hermeneutics of the "I am." (20)

Furthermore, Ricoeur asserts that Heidegger inquires into the "I am" rather that "I think" because Heidegger says that "...which we, the inquirer, are ourselves... This entity which ... each of us is himself and which includes inquiring of one of the possibilities of its Being, we shall denote by the term 'Dasein'." (21) Ricoeur claims that the opposition to the "cogito" in philosophy becomes more subtle since the question of Dasein has a certain priority in the question of Being. Furthermore, "the assertion of the 'cogito sum' proceeds from an essential omission -of an ontology of Dasein" (22) becomes "what Descartes left undetermined...more precisely, the meaning of the being of the 'sum''." (23) Therefore, Heidegger thinks that Descartes not only neglects the question of the being, but also fails to raise the question of the meaning of Being.

Ricoeur holds that the "cogito" is not an innocent statement (24) because it carries an age of metaphysics for which truth is the truth of existence. As the ground of this metaphysics, the existent lies as present in front of us, as a representation in which the subject gets the certainty of things. In the metaphysics of Descartes, the existent is defined as objectivity of representation and truth is defined as the certitude of representation. "With objectivity comes subjectivity in the sense that this being-certain of the object is the counterpart of the position of a subject. (25) In Heidegger's language, this has been so-called "the age of the world picture".

"The whole of modern metaphysics ... was prepared by Descartes." (26) The "I think" is the most dominant influence of Descartes on modern metaphysics, i.e., the idea of subjectivity determines the aims of modern philosophy. The "truth" for modern philosophy is what is represented in our subjectivity. Therefore, Descartes discusses the Archimedean point by the certitude of the "cogito". However, for Flynn, the certitude of the "cogito" is a sort of a syllogistic inference. "All things that think are, I think; therefore I am." (27) This syllogism is not valid because the major premise would simply be asserted and for this reason, the conclusion would remain problematic. Flynn argues that the "cogito" is the place where Being and thought coincide, and the place where to exist and to think I exist is the same thing. (28) On the other hand, Descartes' subject, i.e., "I think", exists absolutely distinct from the external world. Furthermore, for Descartes, in order to have a certitude of truth of subjectivity or "I think", God must exist because He is the guarantor of the finite substances which are the "I think" and the "external world". Keeping in mind that Descartes' God should not be understood as the God of the Judeo-Christian religion, but He is simply a Being in which Being and thought coincide as an infinite Being.

For Heidegger, Descartes liberates the subject from the medieval epoch of Being. (29) In Descartes' philosophy, the subject becomes the transcendental ground of the known and the knowable. Flynn rejects this position of Descartes when he asserts that "the relationship of Being to beings is no longer that of Creator to creatures but rather one of representation to a subject for whom this representation appears, a subject which also appears to itself- represents itself representing." (30) Therefore, Flynn maintains that, for Heidegger, Descartes is a metaphysician who asks the question "what is it to be?". Descartes' answer that to be is to be represented is an attempt to solve an ontological problem by the epistemology of a representation of exterior and of interior.

Levinas discusses Descartes' "cogito sum" as Heidegger does, but each one reaches a different conclusion. C. D. Keyes says that " for Heidegger, Descartes is criticized, among others things, for being neglected to analyze the sum (I am) of the cogito sum,...Descartes leaves the "sum" completely undiscussed." (31) On the other hand, Levinas accepts the Cartesian methodic doubt, but differs from Descartes, where Descartes stops his doubt with the "I think". For Levinas, the "I think" is the wrong place to stop because it is the level of self. This stopping place is an arbitrary one. "The appropriate stopping place is not the I but the Other because the Other alone can say yes, while the I cannot do,..." (32) Therefore, Levinas retrieves the question of Being at a different level, although his interpretation of Descartes' understanding of Being and Heidegger's understanding of Being are not accepted by Keyes. In terms of our discussion, Levinas' interpretation and retrieval of the question of Being shows that "True Being" cannot be explained completely and fully either by Descartes or Heidegger because Levinas tries to go beyond Descartes and Heidegger even though Levinas interprets it correctly or incorrectly.

Being is considered as being-at-hand or extant-at-hand. If Dasein (Being) exhibits an ontological constitution completely different from the being-at-hand, then it means something other than existere, existentia, whatness, reality, and ousia. (33) For Heidegger, the interpretation of the present-at-hand of Dasein is illegitimate because this interpretation is based on the epistemological attitude of "res cogito" who knows and interprets itself as a present-at-hand. But Heidegger maintains that our Being-in-the-world is more than our knowing of present-at-hand of "res cogito". Furthermore, our knowing cannot be explained as present-at-hand and cannot give us access to things in themselves. (34) Heidegger criticizes traditional concepts of time, which belongs to the transcendental context of the knowing subject. Heidegger says that Dasein is neither an individual nor a subject in the traditional sense because beings are in time.

Time has a fundamental ontological function if Being is understood in the light of a temporal horizon. Heidegger gives a definition of time in terms of existential-ontological structure. His understanding of time is not related to those traditional philosophical conceptions which seem to be based on the Aristotle's definition of time as "the measure of motion according to the before and after" (35) which is a perfect formulation of common sense experience of time. In this sense, everyday Dasein finds itself a natural system of measurement in the world of everyday concern. This is a public time or common sense of time that is called the mundane time or worldly time. The mundane time is not fundamental but depends on the ontological structure of Dasein as Care for its very possibility. However, in the traditional definition of time, the ontological structure of the ecstatic care has been forgotten or ignored.

Dasein, is based on the fact that time temporalizes Dasein's Being as care within the world because "temporality makes possible the unity of existence, facticity, and falling, and in this way constitutes primordially the totality of the structure of care. The items of care have not been pieced together cumulatively any more than temporality itself has been put together 'in the course of time' out of the future, the having been, and the present." (36) These three ecstasies of temporality make possible the unity of the multiplicity of Dasein's mode of Being in the possibility of the authentic or the inauthentic existence of Dasein. Therefore, temporality becomes the basic condition for the ontological meaning of care and makes the meaning of Being, Dasein, visible.

In conclusion, we discussed the relation of subject-object in Descartes' and Heidegger's philosophy. We interpreted Descartes' understanding of the relation of subject-object in terms of how Heidegger reads Descartes. So, we will conclude our discussion how Heidegger interprets the duality of Descartes and modern philosophy. Heidegger unifies the duality of modern philosophy. Subject and object (world) belong together in the single entity Dasein. Subject and object are not two beings, because they are the basic determination of Dasein in the unity of the characteristic of Being-in-the-world. Heidegger turns around Descartes' Cogito Sum, and he holds that "Sum" must be asserted first. He formulates "I am-in-the-world" as an understanding of Being: In this sense, Dasein is not a cogito. Dasein and its world can never be separated. Dasein is the Being-in-the-world. Therefore, "I am-in-the-world" precedes the "cogito sum." The truth of cogito is replaced in the disclosedness of Being which is basically primordial truth. Unlike Descartes and others, he breaks the chain of the tradition in terms of an understanding of world. His understanding of Being is Being-in-the-world, but the world of the Being of Dasein is not the physical world. It is the world of Dasein. The world of Dasein belongs to it , and it is a subjective.

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(1) Martin Heidegger, Basic Problems of Phenomenology, Trans. and Intr. by Albert Hofstadter. (Bloomington: Indiana University Press, 1982.), 126.

(2) Ibid., 126.

(3) Ibid., 126.

(4) Charles B. Guignon, Heidegger and the Problem of Knowledge, (Indianapolis: Hackett Pub. Corp., 1983), 161.

(5) Martin Heidegger, Being and Time, Trans. by John Macquarie and Edward Robinson. (New York: Harper and Row Press, 1962.), 59.

(6) Martin Heidegger, Basic Problems of Phenomenology, 174.

(7) Ibid., 174.

(8) Martin Heidegger, Being and Time ,, 87.

(9) Ibid., 88.

(10) Ibid., 87.

(11) Ibid., 368.

(12) Ibid., 368.

(13) Ibid., 368.

(14) Ibid., 369.

(15) Ibid., 365.

(16) Ibid., 368.

(17) Charles B. Guignon, Heidegger and the Problem of Knowledge, 245.

(18) E. F. Kaelin, Heidegger's Being and Time A Reading for Readers, (Tallahassee: Florida State University Press, 1986.), 79.

(19) Paul Ricoeur, "The Critique of Subjectivity and Cogito in the Philosophy of Heidegger", Heidegger and the Quest for Truth. Ed. by Manfred S. Frings. (Chicago: Quadrangle Books, 1968.), 69.

(20) Ibid., 62.

(21) Martin Heidegger, Being and Time, 27.

(22) Paul Ricoeur, "The Critique of Subjectivity and Cogito in the Philosophy of Heidegger", 66.

(23) Martin Heidegger, Being and Time, 46

(24) Paul Ricoeur, "The Critique of Subjectivity and Cogito in the Philosophy of Heidegger", 67.

(25) Ibid., 67.

(26) Martin Heidegger, "Age of the World Picture", The Question of Technology and Other Essays. Trans. by William Levitt. (New York: Harper and Row Pub., 1977.), 127.

(27) Bernard Charles Flynn, "Descartes and the Ontology of Subjectivity", Man and World, (Vol. 16, No: 1, 1983), 10.

(28) Ibid., 10.

(29) Ibid., 14.

(30) Ibid., 14.

(31) C. D. Keyes, "An Evaluation of Levinas: Critique of Heidegger" Research in Phenomenology. (Vol. II, PP 121-142, 1972), 131 and Martin Heidegger, Being and Time 46.

(32) Ibid., 131.

(33) Martin Heidegger, Basic Problems of Phenomenology, 119.

(34) John Richardson, Existential Epistemology: A Heideggerian Critique of Descartes Project, (Oxford: Clarendon Press, 1986), 91.

(35) Aristotle, Physics Book IV The Basic Works of Aristotle. Ed. and Intr. by Richard McKeon. (New York: Random House, 1941.), 219b.

(36) Martin Heidegger, Being and Time , 376.

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