While open-mindedness as an intellectual trait has been recognized for centuries, Western philosophers have not explicitly endorsed it as a virtue until recently. This acknowledgment has been roughly coincident with the rise of virtue epistemology. As with any virtue, it is important to inform contemporary discussion of open-mindedness with reflection on sources from the history of philosophy. Here I do just this. After reviewing two major accounts of open-mindedness, which I dub "Contest" and "Indifference," I explore some ideas pertinent to the subject in four philosophers spanning eighteen centuries: Sextus Empiricus, John Locke, John Stuart Mill, and Paul Feyerabend. Despite their varying concerns and terminology, their contributions may valuably inform current reflection on the virtue of open-mindedness, whether construed in terms of the Contest or Indifference account.
