Various authors have recently expressed doubts about the public relevance of philosophy. These doubts target both academic philosophy in general and particular subfields of philosophy. This paper investigates whether these doubts are justified through two tests in which the lack of public relevance of a philosophical paper is operationalized as the degree to which that paper is isolated. Both tests suggest that academic philosophy in general is more isolated from the broader public than it should be, and confirm the hypothesis (...) that some subfields of philosophy are more isolated than others. We argue that this lack of public relevance is caused by the incentive structure of academic philosophy and discuss a range of individual-level and incentive-level solutions. (shrink)