Abstract
In this thesis I argue that understanding ought to be a central concept investigated by epistemologists. Contemporary epistemologists have largely ignored the concept of understanding, preferring instead to study propositional knowledge. Unlike propositional knowledge, understanding is a cognitive excellence which involves "chunks of information" rather than single propositions. Furthermore, I argue that understanding is distinct even from more complex forms of knowledge; understanding is neither necessary nor sufficient for knowledge. I defend the distinction between knowledge and understanding against possible objections from some recent analyses of knowledge. Finally, I turn to axiological questions and discuss the value of knowledge and the value of understanding over and above true belief. I conclude that any attempt to investigate cognitive excellence in all its forms is incomplete without an inquiry into the nature of understanding