The question of the implications of philosophy for Christian faith was posed in Byzantium in a way different from that in which it occurs in the medieval Latin West. In Byzantium, Christian theology did not become an institutionalized science (as in the West): this could mean both greater room for philosophy and greater precariousness in the face of radical anti-rationalist (in particular monastic) movements. Philosophy could be valued as part of the Hellenic background to Byzantine cultural identity, and, in any case, with rhetoric and law, it formed part of a higher education, indispensable, as such, to Byzantine culture. However, Christian scriptures, vital to Byzantine identity, could also say that philosophy was useless and dangerous (I Cor. i: 18-25; Col. 2: 8). The reactions of Christian writers in the Patristic period were important. At first in competition with philosophical schools, Christian authors (often themselves having philosophical training) asserted their faith as the only true philosophy. Philosophers (Celsus, Porphyry) rejected these claims, provoking Christian refutations by Origen, Methodios of Olympos, Eusebios of Caesarea (and others), who were ready, however, to find value in philosophy as a preparation for faith, as useful in developing an understanding of faith, and as a means for refuting heresies. Clement of Alexandria, Origen, Gregory of Nyssa, Pseudo-Dionysios show, impHcitly or explicitly, this approach. Psellos’ enthusiasm for philosophy, in particular for the (pagan) theology of Proklos, went very far. But in presenting this theology, he noted heretical aspects, distanced himself from them, or removed them (as did Isaak Sevastokrator in his excerpts from Proklos). A developing crisis led to the condemnation of Italos in 1082. The debates between Metochites and Choumnos and between Plethon and Scholarios concerning Plato and Aristotle turned in part on the compatibility of Platonic or Aristotehan philosophy with Christian doctrine (Sevcenko 1962; Byden 2003; Woodhouse 1986). To problematic themes in Platonism (subordination of first causes, eternity of Forms and of matter, pre-existence of souls, metempsychosis) could be opposed difficult positions in Aristotehanism (a first god who exercises little providence, eternity of the world, no feUcity beyond terrestrial existence). However, the late antique commentators left much room for Byzantine thinkers in the interpretation of the exact bearing of these themes and positions. And of course the interpretation of Christian doctrine was itself open to debate in which philosophical ideas could prove influential.