1927 – 2021
Edmund Gettier (1927–2021) was an American analytic philosopher best known for his landmark 1963 paper 'Is Justified True Belief Knowledge?', a three-page article that fundamentally disrupted epistemology. By presenting counterexamples showing that justified true belief is insufficient for knowledge, he invalidated the classical tripartite analysis that had stood since Plato's Meno.
Published 'Is Justified True Belief Knowledge?' (1963), one of the most influential short papers in 20th-century philosophy
Introduced 'Gettier cases': counterexamples demonstrating that justified true belief does not entail knowledge
Invalidated the classical JTB (justified true belief) analysis of knowledge derived from Plato
Sparked a sustained research program in epistemology seeking a fourth condition for knowledge
Demonstrated that a single decisive counterexample can overturn centuries of philosophical consensus