Skep Essay Research Paper An Answer to

Skep Essay, Research Paper

An Answer to Skepticism about Induction and the External WorldThe problems of induction and the external world do indeed share a common structure. Both narrowly define what we “directly” or “immediately” know. They then note that we usually assume that we know much more than that, even though what we know directly does not logically imply most of what we assume we know. Therefore, much of our “knowledge” is unfounded.This paper will undertake three tasks. First, it will outline the general structure of this sort of skeptical argument. Second, it will show how the problems of induction and the external world fit exactly into this common structure. Third, it will point out the most questionable step in the two arguments — which turns out to be the same in both cases.2. The Common Structure of the ProblemsThe problems of induction and the external world, as we shall see later, both fit elegantly into the following, more general skeptical argument:1. X is known directly.2. Y is not known directly.3. X does not logically imply Y, even though we usually assume that it does.(4. Nothing else directly known implies Y either.)Therefore, we don’t know Y.How does this argument work. Basically, it creates a “split” (in Prof. Stroud’s words) between what we know directly and what we don’t know directly. Hence, in order to know the latter, we would have to logically derive it from the former. Sometimes, this isn’t a problem: even though I don’t know that the Pythagorean theorem is true directly, I do know the properties of squares and triangles directly, and the Pythagorean theorem can be logically derived solely from knowledge of squares and triangles. But suppose that I don’t directly know that something is true, and what I know directly does not logically imply it either. I would have to conclude that what I believed was knowledge was just an unwarranted assumption.3. The Structure AppliedI contend that this is exactly what happens with the problems of induction and the external world. In both cases, we start with a premise about what we know directly. Naturally, this is always tiny compared to the entirety of what we assume we know. Our next inclination is to try to deduce, to logically derive, the truth of our other beliefs from the small amount that we know directly. But upon inspection, we see that our other beliefs do not follow logically from what we know directly. So we don’t have any reason to accept these beliefs.Consider how the problem of induction fits into the preceding structure. First, it is admitted that we have direct knowledge of what we currently observe. Second, it is claimed that we don’t have direct knowledge of what we do not currently observe. Third, current observations never logically imply anything about the currently unobserved. As Hume explains, the argument would only work if we knew the law of cause-and-effect. But the latter is not known directly either, and to base it on induction would be circular. So even though we assume that we can base knowledge of the unobserved on our knowledge of the observed, we can’t. Therefore, we have no reason to believe anything about unobserved matters of fact.(This argument is not actually complete. To make it valid, one would also need to know that we couldn’t derive our knowledge of unobserved matters of fact from anything besides our knowledge of observed matters of fact. After all, even if X does not imply Y, another premise, X’, could imply Y. Presumably, Hume did not consider this possibility because he took the distinction between relations of ideas and matters of fact to be exhaustive.)It will be easier to see how the problem of induction fits into the structure outlined in section two by stating the problem of induction more formally:1. Currently observed matters of fact are known directly.2. Currently unobserved matters of fact are not known directly.3. Propositions about currently observed matters of fact do not logically imply propositions about currently unobserved matters of fact, even though we usually assume that they do. (We usually invoke the law of cause-and-effect, which is itself neither known directly nor logically deducible from aynthing known directly.)(4. Nothing else directly known implies any propositions about currently unobserved matters of fact.)Therefore, we don’t know (i.e., have no reason to believe) anything about currently unobserved matters of fact.Now let us compare this to the problem of the external world. Following Descartes, most people will usually say that we directly know only that we have experiences of certain kinds. We directly know that “I feel as if I have a body” or “It looks as if I am seeing green.” So what don’t we directly know. We don’t directly know anything about objects, about real, physical things. We don’t directly know that “I have a body” or “I see green.” To know “physical object” propositions at all, we would have to logically deduce them from knowledge of our experiences. But this is impossible. Since we could be dreaming or having delusions, the mere fact that I know that I am having a certain experience does not logically prove that real, physical objects exist. And again, assuming that nothing else known directly logically implies anything about the real, physical world, the conclusion that we never have any reason to believe anything about the physical world follows.Let us state the argument formally to see how it fits the general argume