Blackwell Reference Online

Extract

The theory of relevant alternatives is best viewed as an attempt to accommodate two opposing strands in our thinking about knowledge. The first is that knowledge is an absolute concept. On one interpretation, this means that the justification or evidence one must have in order to know a proposition p must be sufficient to eliminate all the alternatives to p (where an alternative to a proposition p is a proposition incompatible with p ). That is, one's justification or evidence for p must be sufficient for one to know that every alternative to p is false. This element of our thinking about knowledge is exploited by sceptical arguments. These arguments call our attention to alternatives that our evidence can not eliminate. For example ( Dretske, 1970 ), when we are at the zoo, we might claim to know that we see a zebra on the basis of certain visual evidence, viz. a zebra-like appearance. The sceptic inquires how we know that we are not seeing a cleverly disguised mule. While we do have some evidence against the likelihood of such a deception, intuitively it is not strong enough for us to know that we are not so deceived. By pointing out alternatives of this nature that we cannot eliminate, as well as others with more general application (dreams, hallucinations, etc.), the sceptic appears to show that this requirement that our evidence eliminate every alternative is ... log in or subscribe to read full text