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:
“But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and in the Spirit of our God.”
—Bible: New Testament, 1 Corinthians 6:11.
“It is not true that suffering ennobles the character; happiness does that sometimes, but suffering, for the most part, makes men petty and vindictive.”
—W. Somerset Maugham (1874–1966)
“Hang ideas! They are tramps, vagabonds, knocking at the back- door of your mind, each taking a little of your substance, each carrying away some crumb of that belief in a few simple notions you must cling to if you want to live decently and would like to die easy!”
—Joseph Conrad (1857–1924)