In his earlier writings, Fred Dretske proposed an anti-skeptical strategy that is based on a rejection of the view that knowledge is closed under known entailment. This strategy is seemingly congenial with a sensitivity condition for knowledge, which is often associated with Dretske’s epistemology. However, it is not obvious how Dretske’s early account meshes with the information-theoretic view developed in Knowledge and the Flow of Information. One aim of this paper is to elucidate the connections between these accounts. First I (...) argue that, contrary to an objection raised by Christoph Jäger, the information-theoretic account is compatible with Dretske’s anti-skeptical strategy based on the rejection of closure. This strategy invokes the notion of channel conditions, which are roughly speaking those conditions that are necessary and jointly sufficient for a signal to carry information. I propose an interpretation of the account that is based on the idea that a signal’s carrying information requires that the channel conditions are stable. It is shown that the resulting account incorporates both a sensitivity condition and a safety condition for knowledge. Finally, I demonstrate how this proposal allows for knowledge of modally robust propositions without making its acquisition too easy, as simple safety accounts do. I end with a suggestion concerning the direction that future research should take, based on the fact that in its present form the information-theoretic account does not capture inferential knowledge. (shrink)

Four difficulties with Dretske's theory of knowledge .

A theory of information is developed in which the informational content of a signal (structure, event) can be specified. This content is expressed by a sentence describing the condition at a source on which the properties of a signal depend in some lawful way. Information, as so defined, though perfectly objective, has the kind of semantic property (intentionality) that seems to be needed for an analysis of cognition. Perceptual knowledge is an information-dependent internal state with a content corresponding to the (...) information producing it. This picture of knowledge captures most of what makes knowledge an important cpistcmological notion. It also avoids many of the problems infecting traditional justificational accounts of knowledge (knowledge as [justified, true belief those (unlike knowledge) having a content that can be either true or false (e.g., belief) – are described in terms of the way internal (presumably neural) structures acquire during learning a certain information-carrying role. The content of these structures (whether true or false) is identified with the kind of information they were developed to carry. (shrink)