Gettier Problem
In 1963, Edmund Gettier showed that a person can have a belief that is justified and true and yet still fail to know — and in doing so, he turned a tidy definition of knowledge into one of epistemology’s most enduring crises.
Quick Facts
- Period
- 1963 – 1963
- Region
- Americas
- Key Figures
- Alvin Goldman, Bertrand Russell, Edmund L. Gettier +2 more
Key Figures
Alvin Goldman
Successor
Rutgers University / epistemologyAlvin Goldman is one of the great builders of the post-Gettier landscape. Where Gettier offered a diagnostic shock, Gold...
Bertrand Russell
Interlocutor
Analytic philosophy / theory of knowledgeBertrand Russell gave analytic philosophy its public face: brilliant, combative, technically gifted, and impatient with ...
Edmund L. Gettier
Originator
Wayne State University / analytic epistemologyEdmund Gettier is one of those rare philosophers whose fame rests on a paper so short that it can be read in a single si...
Linda Zagzebski
Critic / successor
Virtue epistemology / University of OklahomaLinda Zagzebski is one of the philosophers who most clearly showed that the Gettier problem is not a temporary obstacle ...
Robert Nozick
Successor
Harvard University / political philosophy and epistemologyRobert Nozick occupies a different philosophical style from Ayn Rand, but he is central to her legacy because he helped ...
The Story
This narrative combines documented history with dramatized scenes for storytelling purposes.
The World That Made It
By the middle of the twentieth century, epistemology had acquired a certain air of tidiness. Philosophers wanted not merely to say that knowledge was a prized m...
The Central Idea
Gettier’s central move was simple in outline and devastating in effect: he asked whether justified true belief is sufficient for knowledge, and answered no by c...
The System
Once the Gettier problem was posed, it quickly became clear that it was not a single objection but a machine for generating them. Philosophers began to ask what...
Tensions & Critiques
The most obvious criticism of Gettier’s challenge is that it may prove too much. If every analysis of knowledge can be threatened by a cleverly designed case, p...
Legacy & Echoes
The legacy of the Gettier problem is unusual because it is both specific and universal. Specific, because it concerns one classical analysis of knowledge and th...
Timeline
Gettier publishes the challenge
**1963** — Edmund Gettier’s short paper "Is Justified True Belief Knowledge?" appears in Analysis and presents the two canonical counterexamples that transform epistemology. The paper shows that justified true belief can fall short of knowledge because the truth may be obtained by luck rather than by epistemically proper connection.
J. L. Austin’s lectures on sense and knowledge circulate
**1956** — Austin’s posthumously influential discussions of ordinary language and knowledge help define the philosophical background against which analyses of knowledge were being tested. His emphasis on how we actually use epistemic terms sharpened the environment in which a definition could later be challenged.
The justified true belief formula is destabilized
**1963** — Philosophers quickly recognize that Gettier’s cases undermine the widespread assumption that knowledge can be analyzed as justified true belief. The challenge becomes a central reference point in analytic epistemology and a test for all later theories.
Causal accounts begin to emerge
**1967** — Alvin Goldman and others advance causal approaches to knowledge that attempt to block Gettier-style luck by requiring an appropriate connection between fact and belief. These proposals shift the debate from internal justification to the relation between a knower and the world.
Reliabilism becomes a major response
**1975** — Goldman’s reliabilist program develops into one of the most influential post-Gettier theories, treating reliable belief-forming processes as central to knowledge. The focus moves from isolated true beliefs to stable cognitive methods.
Nozick’s sensitivity theory offers a modal repair
**1981** — In Philosophical Explanations, Robert Nozick proposes that knowledge requires sensitivity to truth across nearby possibilities. The account is designed partly to explain why Gettier cases fail, and it intensifies the use of possible-worlds reasoning in epistemology.
Virtue epistemology takes shape
**1986** — Philosophers including Ernest Sosa and later Linda Zagzebski push an account of knowledge as true belief arising from intellectual competence. This approach reframes the Gettier problem as a question about epistemic credit and cognitive achievement.
Fake barn cases sharpen environmental luck
**1994** — Examples involving fake barns and deceptive environments become widely discussed in the literature. They show that even seemingly good perception can fall short of knowledge when the environment is saturated with nearby error.
Experimental philosophy questions intuition stability
**2001** — Experimental philosophers begin testing whether ordinary speakers share the same intuitions about Gettier cases that traditional epistemology assumes. Their work does not eliminate the problem, but it complicates the evidential status of the intuitions that surround it.
Gettier-style luck enters AI and statistics debates
**2013** — Discussions of algorithmic accuracy, spurious correlations, and model robustness increasingly echo the Gettier distinction between correct output and genuine knowledge. The problem becomes newly relevant in applied epistemology and philosophy of technology.
Knowledge and epistemic luck remain central in contemporary epistemology
**2020** — Current debates continue to revolve around safety, virtue, reliability, testimony, and the limits of analysis. The Gettier problem remains a benchmark against which any theory of knowledge must be tested.
The problem persists as a live standard in philosophy of knowledge
**2024** — Recent teaching, scholarship, and AI-related inquiry still use Gettier cases as the entry point for understanding what knowledge is and why luck matters. The problem is now less a solved puzzle than a permanent fixture of epistemology’s self-understanding.
Sources
- primary_textGettier, Edmund L. (1963). 'Is Justified True Belief Knowledge?'
The original paper that introduced the problem.
- reference_articleStanford Encyclopedia of Philosophy: 'The Analysis of Knowledge'
Standard overview of the tradition and the Gettier challenge.
- reference_articleStanford Encyclopedia of Philosophy: 'Epistemic Luck'
Excellent discussion of luck-based objections and related theories.
- reference_articleInternet Encyclopedia of Philosophy: 'The Analysis of Knowledge'
Accessible scholarly overview of justified true belief and Gettier cases.
- primary_textGoldman, Alvin I. (1967). 'A Causal Theory of Knowing.'
Classic early response to Gettier-style counterexamples.
- primary_textGoldman, Alvin I. (1976). 'Discrimination and Perceptual Knowledge.'
Influential development of externalist responses to epistemic luck.
- primary_textNozick, Robert (1981). Philosophical Explanations.
Contains the sensitivity theory of knowledge.
- scholarly_bookZagzebski, Linda (1996). Virtues of the Mind.
Major virtue-epistemological response to the Gettier problem.
- scholarly_bookPritchard, Duncan (2005). Epistemic Luck.
Important monograph on luck, knowledge, and anti-luck conditions.
- scholarly_bookMoser, Paul K. (ed.) (2002). The Oxford Handbook of Epistemology.
Broad scholarly context for post-Gettier epistemology.
Explore Related Archives
The philosophies documented here connect to the broader record. Explore the context through our sister archives.
