Abstract: Abstract This chapter puts Wittgenstein’s discussion of rule-following and privacy to novel use in an argument for physicalism about the mind. The chapter proceeds with evident concern to keep controversy and complications regarding the issues of rule-following and privacy to a minimum. It thus lays down what he takes to be more or less common ground on these topics and attempts to derive from it a physicalist thesis. The chapter makes interesting use of the distinction Wittgenstein draws between the first-person and third-person perspectives. Only if we attend to this distinction, this chapter argues, will we see that Wittgenstein’s diagnosis of the difficulties concerning rule-following and privacy ultimately supports a kind of mind-brain identity thesis. This is so, the chapter notes, even if Wittgenstein did not himself espouse physicalism.