The Gettier Case: Ford in the Office

The case

Your colleague Brown has always driven a Ford. He drove one last year, the year before, and as far as you know, he drives one now. On the basis of this strong evidence, you form the belief: "someone in my office owns a Ford."

Unknown to you, Brown sold his Ford last week and is currently renting a car. But another colleague, someone you had no particular reason to think about, happens to own a Ford. Your belief is true: someone in your office does own a Ford. And it is justified: you had excellent evidence for it. But the belief is true in a way that has nothing to do with your evidence or your reasoning. You got lucky.

Why this refutes the standard analysis

Since Plato's Theaetetus, philosophers had generally held that knowledge is justified true belief: a belief that is true and that you have good reason to hold. Gettier's case shows this is not sufficient. You can have all three conditions satisfied, true belief, justified, and still fall short of knowledge.

The problem is the gap between your justification and the truth of your belief. Your evidence pointed at Brown, and Brown's Ford turned out not to exist. The belief came out true anyway, through a completely independent route. That kind of accidental truth doesn't feel like knowledge, and the intuition here is strong enough to be taken seriously.

Epistemic luck

What Gettier cases reveal is that knowledge requires ruling out a specific kind of epistemic luck: the luck of being right through a route disconnected from the route that justified you. This is different from the ordinary luck of guessing correctly. You didn't guess. You reasoned well. But the world cooperated in the wrong way.

Philosophers since 1963 have proposed dozens of conditions to add to justified true belief to close the gap: a no-false-lemma condition, a sensitivity condition, a safety condition, a causal connection requirement, and many others. None has achieved universal acceptance. The Gettier problem remains open, which is part of why it changed epistemology so permanently.