CURRENT CONTROVERSIES about the Mind-Body Identity Theory form a case-study for the investigation of the methods practiced by linguistic philosophers. Recent criticisms of these methods question that philosophers can discern lines of demarcation between "categories" of entities, and thereby diagnose "conceptual confusions" in "reductionist" philosophical theories. Such doubts arise once we see that it is very difficult, and perhaps impossible, to draw a firm line between the "conceptual" and the "empirical," and thus to differentiate between a statement embodying a conceptual (...) confusion and one that expresses a surprising empirical result. The proponent of the Identity Theory are identical with certain brain-processes) holds that his opponents' arguments to the effect that empirical inquiry could not identify brain-processes and sensations are admirable illustrations of this difficulty. For, he argues, the classifications of linguistic expressions that are the ground of his opponents' criticism are classifications of a language which is as it is because it is the language spoken at a given stage of empirical inquiry. But the sort of empirical results that would show brain processes and sensations to be identical would also bring about changes in our ways of speaking. These changes would make these classifications out of date. To argue against the Identity Theory on the basis of the way we talk now is like arguing against an assertion that supernatural phenomena are identical with certain natural phenomena on the basis of the way in which superstitious people talk. There is simply no such thing as a method of classifying linguistic expressions that has results guaranteed to remain intact despite the results of future empirical inquiry. Thus in this area there is no method which will have the sort of magisterial neutrality of which linguistic philosophers fondly dream. (shrink)

Nevertheless, despite whatever optimism about the future unification of sciences is justified, there are now, as there have been for centuries, difficult problems confronting the materialist. Perhaps the crucial problem concerns the status of sensations, a problem clearly evident as far back as Hobbes who said that sense is "some internal motion in the sentient, generated by some internal motion, of the parts of the object, and propagated through all the media to the innermost part of the organ." Here Hobbes (...) reduces sense to physical motion. But he is also found to say that sense is not motion, but "in all cases, is nothing else but original fancy," or, he says elsewhere, "phantasms" caused by internal motions. He is then directly faced with the problem of reconciling appearances and sensations with his avowed materialism. Neither Hobbes nor any one else has solved this problem, although there have recently been some novel and instructive attempts to do so. (shrink)

Some materialists argue that we can eliminate mental entities such as sensations because, like electrons, they are theoretical entities postulated as parts of scientific explanations, but, unlike electrons, they are unnecessary for such explanations. As Quine says, any explanatory role of mental entities can be played by "correlative physiological states and events instead." But sensations are not postulated theoretical entities. This is shown by proposing definitions of the related terms, 'observation term,' and 'theoretical term,' and then classifying the term 'sensation.' (...) The result is that although 'sensation' is a theoretical term, it is also a reporting term because it is used to refer to phenomena we are aware of. Consequently sensations are not postulated and cannot be eliminated merely because they are unnecessary for explanation. (shrink)