Henry drives through countryside where 99% of barn-shaped structures are fake facades, but he stops in front of the one real barn and forms the belief 'there is a barn in front of me.' Does his belief satisfy the safety condition?
AYes — Henry is actually looking at a real barn, so his belief is true in the actual world
BYes — Henry's belief is justified by normal perceptual faculties, which is all safety requires
CNo — in nearby possible worlds where he holds the same belief by the same method, he is mostly looking at facades, so his belief would frequently be false
DNo — safety requires that Henry know he is in fake-barn country before his belief can be assessed
Safety asks: in nearby worlds where you hold this belief by the same method, is the belief true? In worlds close to Henry's — also driving through fake-barn country, also relying on visual appearance — he would mostly be facing facades, and his belief 'there is a barn' would be false. Safety fails. His actual-world success is a matter of luck: he happened to stop at the one real barn, but his belief-forming method would easily have produced a false belief. This modal fragility is what anti-luck conditions are designed to capture.
Question 2 Multiple Choice
How does the sensitivity condition explain why Henry's barn belief fails to constitute knowledge?
ASensitivity fails because Henry would still believe 'there is a barn' even if there were no barn — he would be looking at a convincing facade
BSensitivity fails because Henry cannot introspectively verify whether he is in fake-barn country
CSensitivity is satisfied here, which shows sensitivity alone cannot explain the barn case
DSensitivity requires that the belief track truth across all possible worlds, not only the nearest ones
Sensitivity (Nozick) requires: if P were false, you would not believe P. For Henry: if there were no barn in front of him, he would still believe there was one — he would be looking at an indistinguishable facade. The nearest 'no barn here' worlds are accessible, and his belief survives in them unchanged. Sensitivity fails, diagnosing the barn case as non-knowledge. His belief does not track the truth: it would persist even in error-worlds close to his actual situation.
Question 3 True / False
A belief that satisfies the safety condition should also satisfy the sensitivity condition, and vice versa — the two conditions are equivalent.
TTrue
FFalse
Answer: False
Safety and sensitivity can come apart. Lottery cases illustrate this: my pre-draw belief that I will not win satisfies sensitivity (if I had won, I would believe I had won — I'd see the ticket) but may fail safety (in nearby worlds where I hold that belief, there is a small but non-negligible chance I do win). Other cases push in the other direction. The conditions encode different modal relationships: sensitivity concerns what happens if the content is false; safety concerns what happens in nearby worlds where the belief is held. They are not equivalent.
Question 4 True / False
Anti-luck conditions require that knowledge is incompatible with any element of luck — even ordinary epistemic luck like being in the right place at the right time to observe an event.
TTrue
FFalse
Answer: False
Anti-luck accounts specifically target the kind of epistemic luck that severs the reliable connection between belief and truth — where you happen to be right but would easily have been wrong. Not all luck undermines knowledge. That you were lucky to glance up just as the rare bird flew past does not prevent you from knowing you saw it. The problematic luck is revealed by the counterfactual structure: if your belief would survive in nearby worlds where it is false, the connection between belief and truth is fragile, not robust. This is the relevant kind of luck, not luck in the circumstances of evidence-gathering.
Question 5 Short Answer
Why do Gettier cases fail anti-luck conditions? Describe the modal structure that shows the belief is only luckily true.
Think about your answer, then reveal below.
Model answer: In Gettier cases, the actual world cooperates with the belief, but nearby counterfactual worlds do not. For the barn case: Henry believes truly in the actual world, but in very similar worlds — nearby in the space of possibilities — he is looking at a facade and his belief is false. The safety condition is violated: his belief-forming method frequently yields false beliefs in close worlds. The belief is 'fragile': it is true only because the actual world happened to place a real barn at Henry's stopping point, not because his belief-forming process reliably tracks truth. Anti-luck conditions reveal that Gettier cases lack the robust modal connection between belief and truth that knowledge requires.
The shift from justified true belief to anti-luck conditions relocates the analysis: instead of asking 'is this belief justified and true?', we ask 'does this belief reliably track truth across the nearby counterfactual landscape?' Gettier cases pass the first test but fail the second — their truth is accidental, not structural.