Sensation and Scientific Realism

Abstract

Paul Churchland [3] has persuasively and elegantly argued for the increasingly more popular thesis that an agent's observation judgments are determined by the theories the agent espouses. In league with Sellars [23] and Feyerabend [9], [io], Churchland opposes the myth of the sensuously given, repudiating the classical and fundamental empiricist distinction between the sensible and nonsensible, between what can be perceived and what can only be inferred from what can be perceived. Our senses, according to Churchland, are malleable receptors, capable of transmitting much of the massive amount of information available in the ambient array expressible in the general theories to which we, as sensors, subscribe. Thus, you and I, both familiar with the popular conception of color and the semantic network of 'red', apparently can sense the setting sun as red. But you, not I, may be versed in the details of astrophysics. So you, though not I, may, in the same act of sensing, directly sense, not infer from what you sense, the sun as emitting radiation shifting towards the longer wavelengths while the shorter are increasingly scattered away from the lengthening atmospheric path they must take as terrestrial rotation turns us slowly away from their source [3, p. 29]. For Churchland, then, our senses are measuring and detecting instruments amenable to constant recalibration and reinterpretation in terms of whatever new, true theoretical world view we may happen to enjoy. And this is consistent with, indeed predicated on, scientific realism [3, pp. 2-3]. Churchland's general thesis may be correct, sensuous judgments may be thoroughly theoretical. Nevertheless, I want to urge that Churchland's analysis of sensation is flawed. For his scientific realism, I contend, entails a more restrictive account of the plasticity of sensation than the one he proposes. Churchland, with Sellars [23, pp. I32-34], distinguishes between two notions or types of sensation. An objectively intentional sensation, is a noncognitive state of an agent that carries information [8] about the