In this interpretive commentary on Theaetetus, Gregory Kirk makes a major con­tribution to scholarship on Plato by emphasizing the relevance of the interpersonal dynamics between the interlocutors for the interpretation of the dialogue’s central arguments about knowledge. Kirk attends closely to the personalities of the participants in the dialogue, focusing especially on the unique demands faced by a student—in this case, Theaetetus—and the ways in which one can embrace or deflect the responsibilities of learning. Kirk’s approach gives equal consideration to the dual demands of dramatic interpretation and philosophical argument that constitute the unique character of the Platonic text, and he develops an original interpretation of the Theaetetus, concluding that the uncertainty that characterizes wisdom supersedes the certainty of knowledge.