b. 1936
Keith Lehrer is an American philosopher known for his influential contributions to epistemology, particularly his defeasibility theory of knowledge and his work on consensus, autonomy, and rational acceptance. His Gettier-style counterexamples to various analyses of knowledge have been widely discussed in analytic epistemology.
Developed the defeasibility theory of knowledge as an alternative to justified true belief
Co-authored the Lehrer-Paxson analysis of knowledge addressing Gettier problems
Formulated influential counterexamples to externalist and internalist theories of justification
Authored 'Knowledge' (1974) and 'Theory of Knowledge' (1990), both major epistemology textbooks
Advanced theories of rational consensus and social epistemology
Because the agent's aversive mood is fragile, the possibility of her trying to eat a red candy is a close one, so she also satisfies condition (ii).
premiseDespite satisfying both (i) and (ii), this agent lacks the ability to eat a red candy in precisely the same way as Lehrer's original agent.
premisePeacocke's proposal requires that an agent satisfy both condition (i) and condition (ii) to possess an ability.
premiseAn agent whose aversion to red candies is an unpredictable and temporary mood satisfies condition (i) for the same reason as Lehrer's original agent.
Because the agent's aversive mood is fragile, the possibility of her trying to eat a red candy is a close one, so she also satisfies condition (ii).
premiseDespite satisfying both (i) and (ii), this agent lacks the ability to eat a red candy in precisely the same way as Lehrer's original agent.
claimPeacocke's proposal is subject to modified versions of Lehrer's counterexample and therefore fails to overcome the sufficiency objection.
premiseAn agent whose aversion to red candies is an unpredictable and temporary mood satisfies condition (i) for the same reason as Lehrer's original agent.