Studies of the icon in Byzantium have tended to focus on the iconoclastic era of the eighth- and ninth-centuries. This study shows that discussion of the icon was far from settled by this lengthy dispute. While the theory of the icon in Byzantium was governed by a logical understanding that had limited painting to the visible alone, the four authors addressed in this book struggled with this constraint. Symeon the New Theologian, driven by a desire for divine vision, chose, effectively, to disregard the icon. Michael Psellos used a profound neoplatonism to examine the relationship between an icon and miracles. Eustratios of Nicaea followed the logic of painting to the point at which he could clarify a distinction between painting from theology. Leo of Chalcedon attempted to describe a formal presence in the divine portrait of Christ. All told, these authors open perspectives on the icon that enrich and expand our own modernist understanding of this crucial medium.