Justified true belief is a definition of knowledge that is most frequently credited to Plato and his dialogues. The concept of justified true belief states that in order to know that a given proposition is true, one must not only believe the relevant true proposition, but one must also have justification for doing so. In more formal terms, a subject S knows that a proposition P is true if and only if:
- P is true
- S believes that P is true, and
- S is justified in believing that P is true
This theory of knowledge suffered a significant setback with the discovery of Gettier problems, situations in which the above conditions were seemingly met but that many philosophers disagree that anything is known. Robert Nozick suggested a clarification of "justification" which he believed eliminates the problem: the justification has to be such that were the justification false, the knowledge would be false.
Famous quotes containing the words justified, true and/or belief:
“Strikes and boycotting are akin to war, and can be justified only on grounds analogous to those which justify war, viz., intolerable injustice and oppression.”
—Rutherford Birchard Hayes (1822–1893)
“False greatness is unsociable and remote: conscious of its own frailty, it hides, or at least averts its face, and reveals itself only enough to create an illusion and not be recognized as the meanness that it really is. True greatness is free, kind, familiar and popular; it lets itself be touched and handled, it loses nothing by being seen at close quarters; the better one knows it, the more one admires it.”
—Jean De La Bruyère (1645–1696)
“The belief that all genuine education comes about through experience does not mean that all experiences are genuinely or equally educative.”
—John Dewey (1859–1952)