As part of the panel, "Reason, ‘Science' and Anthropology - the Role of Early Christian Thought in a Perennial Debate", with Karla Pollmann, Pablo de Felipe and Alexandra Parvan, this paper will discuss how the human mind is examined and conceived within the framework of a late-Byzantine martyr's text. The story of the late-antique saint, Tatiana of Rome, was re-written in the ninth-eleventh centuries and subsequently enjoyed further popularity in the fourteenth century, the Palaiologan era. A prominent theme that emerges in the adapted text is the mind's capacity for irrational behaviour and its subsequent effects. The emphasis on reason is further extended to a clarification of late-antique beliefs in the fantastical and unreal that formed part of early Christian belief, which are now transformed into an adjusted Byzantine ‘reality'. These amendments are located within a Christian framework where the figure of Tatiana is re-written to become a rational orator, whose mission is to emphasis Christianity's place in a world that, on one level, inside the text, was being annihilated by paganism and, outside the text, was increasingly being dominated by Islam as well as fractured by domestic religious and political disputes. The adaptation of a relatively unknown story, which then gains popularity in a later era, illustrates hagiography's capability to signify meaning in any period of history. In this particular text, this meaning is the anonymous author's way of making sense of his world.