Ideas have lives of their own. Their genealogies, careers, mutations, and legacies form historical patterns and ontologies different from those of individual human beings and societies, though they are linked to them in manifold ways. Ideally, the history of ideas should be studied diachronically and across the boundaries of states, cultures, and periods, these being the most important categories that artificially break up intellectual history. 1 Yet the questions of how the Byzantines interacted with ideas which they received from earlier periods, and how they developed ideas of their own, are occluded in existing scholarship. It is typical for diachronic studies to jump from antiquity to the Renaissance, reinforcing a particular concept of the genealogy of the "west." Intellectual histories of the medieval west rarely include the Byzantine world, 2 even though the western tradition draws from the same Greek, Roman, and Christian sources that were also part of the Byzantine patrimony. Moreover, within Byzantine Studies intellectual history is probably the least developed subfield, lacking titles to its name and definition in relation to other inflections of historical inquiry. We have therefore chosen the format of an Intellectual History of Byzantium as a preliminary step toward rectifying this imbalance: first, to provide the resources with which more integrated cross-cultural, diachronic, and analytical narratives may one day be written, and, second, to spur the growing interest in Byzantine intellectual history as a more or less distinct discipline.why byzantine intellectual history is important Not only did the Byzantines develop a vibrant and complex intellectual culture for themselves, they can justly claim an important place in the intellectual history of the world. In an ideal world driven by genuine intellectual curiosity, cultures would be regarded as fascinating and worthy of study for their own sake. But as we live in more utilitarian times, it is necessary to list some of the contributions that Byzantium made to cultures