The fifteenth-century Spanish theologian Juan de Segovia is known primarily as a leading proponent of late medieval conciliarism and, to a lesser degree, as an advocate of peaceful resolution to Christian-Muslim conflict. Scholars who have studied Segovia's Islamicism have generally emphasized his originality and his progressive approach. As a corrective to this justifiable view, the present article outlines the traditional elements in Segovia's portrayal of Islam, because these elements constitute rather an obstacle to Segovia's own pacifistic approach. In addition, this article suggests a connection between Segovia's Islamicism and his conciliarism that hinges on the notion of truth. It is argued that Segovia's university background provides the crucial context for his understanding of truth, and thus for his views on ecclesiological as well as inter-religious conflict.