Edmund Gettier

Key ideas

For centuries many philosophers assumed that knowledge is justified true belief. In 1963 Gettier gave two short counterexamples. In each, someone has a belief that is justified and true, but true only by luck, and so does not seem to count as knowledge.

The Gettier problem set off decades of attempts to add a fourth condition or replace justification altogether, through theories such as reliabilism, none of which has won general agreement.

Life, briefly

Gettier was teaching at Wayne State University in Detroit when, according to colleagues, he wrote the paper partly because he needed a publication for tenure. He later taught for decades at the University of Massachusetts Amherst. He published almost nothing else, saying he had nothing more to say.

Major works

• Is Justified True Belief Knowledge? (1963)

Further reading

• WikipediaEdmund Gettier