Fact-tracking belief and the backward clock: a reply to Adams, Barker and Clarke

Abstract

In “The Backward Clock, Truth-Tracking, and Safety” (2015), Neil Sinhababu and I gave Backward Clock, a counterexample to Robert Nozick’s (1981) truth-tracking analysis of knowledge. In “Knowledge as Fact-Tracking True Belief” (2017), Fred Adams, John Barker and Murray Clarke propose that a true belief constitutes knowledge if and only if it is based on reasons that are sensitive to the fact that makes it true, that is, reasons that wouldn’t obtain if the belief weren’t true. They argue that their analysis evades Backward Clock. Here I show that it doesn’t. Backward Clock likewise shows their analysis to be too weak. The broader lesson seems to be that Backward Clock tells us the time is up for purely modal analyses of knowledge.