In this book, Nathaniel P. Sharadin argues for rejecting epistemic instrumentalism as a first-order view not because it suffers extensional failures, but because it suffers explanatory ones. By contrast, he argues that epistemic instrumentalism offers a natural, straightforward explanation of why being epistemically correct matters. What emerges is a second-order instrumentalist explanation for epistemic authority that is neutral between competing first-order epistemic theories. This neutrality is an advantage. But, drawing on work from cognitive science and psychology, Sharadin argues that instrumentalists can abandon that neutrality in order to adopt a view he calls epistemic ecologism. will be of interest to researchers and advanced students working in epistemology, ethics, and philosophy of mind.