Justified True Belief

  • According to Plato, true belief is not enough for knowledge
    • It must be justified
    • Person who is justified is in a position to speak to objections of their belief
      • A lucky guesser will have more trouble defending their belief
  • In order for something to be true, one must not only believe the relevant true proposition, but also have justification for doing so
  • $S$ knows that $P$ if any only if:
    • $P$ is true
    • $S$ believes that $P$ is true
    • $S$ is justified in believing that $P$ is true