Defeating the Externalist’s Demons

This chapter is about the New Evil Demon problem for externalist accounts of rationality. The New Evil Demon problem plagues views that hold that what is rational is not solely determined by internal states of the agent. To solve the New Evil Demon problem one has to show that internal state duplicates—agents who share all (and only) the same internal states—always share the same rational status. This chapter argues that Reasons Responsiveness can solve the New Evil Demon problem. It is argued that even though not all internal state duplicates share the same reasons, they do always share the same rational status. The chapter also argues that Reasons Responsiveness solves several problems related to the New Evil Demon problem. These include problems about getting knowledge from falsehoods, non-veridical perceptual justification, and a problem about reacting to reasons I call the New New Evil Demon problem.