Karl Rahner’s Theory of Sensation

KARL RAHNER'S THEORY OF SENSATION IN AN AGE when theories of sense perception include a wealth of physiological and psychological sophistication, Karl Rahner's theory might seem like an anachronism, an unnecessary resurrection of a pre-scientific and long-abandoned theory. But this is so only if we misunderstand the direction of Rahner's approach to the problem of sensation. The usual contemporary treatment of sensation is empirical. The method is to take a cold, hard, philosophical look at the workings of sensation in order to determine its ontological structure . Such an approach necessarily entails information gathered from the various sciences which deal with the complex act of human sensation. Rahner, however, does not proceed in this empirical way. His method is to determine what the ontological structure of sensation must be1 given certain previous factual and logical commitments. In other words, Rahner approaches the problem of sensation with a transcendental methodology. Kant's theory of mind in the Critique of Pure Reason is not arrived at by examination of, and reflection on, the workings of mind; it is a deduction of what mind must be, given certain prior, intellectual commitments. Kant had previously determined both that man did, in physics and mathematics, possess synthetic, necessary knowledge and that, agreeing with Hume, this necessity could never come from experience. The Critique,. then, is a deduction of what mind must be, given these two prior commitments. The force of Kant's intellectual achievement can only be understood within the context of his transcendental method. Rahner's theory of sensation proceeds in a transcendental manner similar to Kant's. Rahner begins his deduction of the nature of sensibility with two previously established intellectual commitments: the nature of knowledge as the self-presence of 400 KARL RAHNER ON SENSATION 401 being and the seemingly contradictory fact that human knowledge is receptive. It is only in grasping the strength of these initial commitments that the force of Rahner's transcendental deduction of the nature of sensibility can be understood. Therefore, my exposition of Rahner's theory will follow the precise form of his transcendental deduction. The first part will be an exposition of Rahner's commitment to the essence of knowledge as self-presence of being. The second part will take this commitment, along with the obvious fact that man's knowledge is intentional, and attempt to determine what the ontological structure of man must be in order to explain these facts. The third part is an attempt to outline the mechanics of .sensation. The previous section will determine what sensation must do; this section will determine how it goes about doing what it does. To again use Kant's deduction as an example: Kant first determines that mind must form (cause) experience; he then attempts to show how it does so by means of a transcendental determination of time. Rahner's theory of sensation also ends with a treatment of its " mechanics." Two possible difficulties must be clarified before we begin our exposition of Rahner'.s theory. The first is that his theory is primarily contained in Spirit in the World, his doctoral dissertation , which is itself an exposition of Aquinas' metaphysics of knowledge. I am going to assume that Rabner has dealt creatively enough with the Thomistic texts to entitle him to call the theory of sensation presented in Spirit in the World his own-though a grounding in Thomistic principles is certainly undeniable. This assumption 1 will simplify my task. Rabner is concerned with proving that the metaphysics of knowledge which he presents is Thomistic. Thus, he devotes much time and effort to defining and explaining Thomistic terminology and trying to bring its multiplicity into a clear, essential unity. 1 This assumption, though incapable of verification here, is not unfounded. Rahner's dissertation was rejected as a work of Thomistic scholarship by Martin Honecker. 402 JAMES J. CONLON This paper is not concerned with whether Rahner's theory is Thomistic. I believe that the fundamentals of Rahner's theory, at no point, are based on any argument from authority, but are grounded independently of Aquinas. Therefore, this paper presents the theory as Rahner's own and attempts to avoid, in...