 The three opuscula sacra written to analyse points of Christian doctrine seem to have been occasioned by events of the time. Treatise V, against Eutyches and Nestorius, was apparently inspired by a letter (c. 513) from a group of Greek bishops, proposing a Christological formula which, they hoped, would unite the Western and Eastern Churches. The two treatises on the Trinity (II is a partial sketch for I) are probably related to the intervention in 519 by a group of Scythian monks, also designed to heal the schism. The works have, however, an interest far beyond their contributions to the immediate doctrinal debate. They pioneer a method of using logical analysis in a theological context which Augustine had anticipated but not developed. Both heretical positions (for examples, the views about Christ and human nature held by Eutyches and Nestorius) and orthodox Christian doctrine are subjected to rigorous scrutiny, using the techniques of Aristotelian logic and, where necessary, ideas from Aristotelian physics. The heretical ideas are shown to contain logical contradictions. As for the orthodox understanding of God, it does not fit within the classifications of Aristotelian logic and natural science, but Boethius tries to chart exactly how far these distinctions, which are accommodated to the created world, also apply to the deity, and at what point they break down and provide us merely with an analogy.