Triangulation between Internalism and Externalism

The disputes between externalism and internalism in philosophy of mind, on the one hand, and epistemology, on the other, do not seem at least prima facie to be deeply intertwined. I believe that this is not really the case, however, and that the theory of triangulation—developed by Donald Davidson in the last two decades of his life—is a clear example of how considerations about the nature of mental content, justification, and knowledge may be interdependent. In this paper I shall analyze Davidson’s “triangular” externalism about mental content in relation both to his coherence theory of justification (which may be regarded as a kind of epistemic internalism), and to his attempt to offer an answer to the skeptic. First of all, I shall consider the thesis that content externalism cannot be compatible with epistemic internalism, and argue against it that there is no tension between triangular externalism and Davidson’s internalism of justification. Secondly, I shall not only demonstrate that triangular externalism supports Davidson’s thesis that belief is in its nature veridical, but also claim that such a result is probably not enough to offer a satisfactory argument against the skeptic about the external world.