Heidegger's Reading of Descartes' Dualism
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.
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...