Single Idea 6589

[catalogued under 13. Knowledge Criteria / A. Justification Problems / 1. Justification / c. Defeasibility]

Full Idea

In general a knowledge claim is legitimate only if all relevant defeaters have been eliminated.

Clarification

A 'defeator' would undermine someone's claim to know something

Gist of Idea

Knowledge is legitimate only if all relevant defeaters have been eliminated

Source

Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4)

Book Reference

Fogelin,Robert: 'Walking the Tightrope of Reason' [OUP 2004], p.102


A Reaction

The problem here is what is 'relevant'. Fogelin's example is 'Are you sure the suspect doesn't have a twin brother?' If virtual reality is relevant, most knowledge is defeated. Certainly, imaginative people feel that they know less than others.