This article aims at revealing the details of the reception of a philosophical doctrine, emerged firstly in ancient Greek thought from the aspiration of answering to the question of how the virtues are related, by one of the foremost figures of Islamic Philosophy, Raghib al-Isfahani (d. V./XIth Century). The doctrine, which is called "The Unity of the Virtues" in modern ethical literature, was accepted and after a particular kind of interpretation, was transformed into a solution by him. However, this solution was encapsulated, and as is, it is far away from giving satisfactory responses to the inquiries intended for its consistency and explanatoriness. Thereby, it needs to be grounded and elaborated by staying within the boundaries of the philosophy of al-Isfahani. To that end, this paper will firstly show how the doctrine emerged and then analyze its reception by al-Isfahani.