Although the topic of this study is ancient, the question of the value of belief and its distinction from knowledge remains both relevant and difficult to answer. Plato’s notion of δόξα cannot be straightforwardly equated with a modern understanding of belief, nor can the distinction between belief and knowledge be resolved through a single framework applicable to both ancient and modern theories. Nevertheless, engaging with Plato’s epistemological reflections not only contributes to scholarship but also fosters critical thinking about the validity of belief and the processes by which belief and knowledge are formed. The Introduction to this study outlines its four guiding questions and explains the selection of dialogues to be examined, together with an overview of prior research on δόξα in Plato. It also sets out the methodological approach and structure of the study. By means of a comparative, systematic, and exegetical analysis of key arguments, this work aims to offer a fresh appraisal of δόξα in Plato, with particular attention to the positive role that belief plays in his epistemological conceptions.