Justified True Belief

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:

  1. P is true
  2. S believes that P is true, and
  3. 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:

    ... like anyone else who does not have a soul, you cannot stand anyone who has too much of one. Too much soul! That is troublesome, is it not? So, it is called a sickness: the eggheads are justified and happy.
    Albert Camus (1913–1960)

    ... the true seeing is within; and painting stares at you with an insistent imperfection.
    George Eliot [Mary Ann (or Marian)

    A belief which leaves no place for doubt is not a belief; it is a superstition.
    José Bergamín (1895–1983)