How Many Books Does It Take to Make an Emperor's Library? Constantine VII Porphyrogenitus and a Chapter of History of the Manuscript Book

In tenth-century Byzantium, the Emperor Constantine VII Porphyrogenitus commissioned a series of works that aimed to collect and select the knowledge accumulated over the centuries. In the Excerpta Constantiniana this enormous material was distributed in 53 treatises, divided into specific book units and meticulously numbered. A survey of other textual traditions – Epictetus’s Handbook, Evagrius’s De oratione, Nilus’s Correspondence – shows that the choice of this number is not accidental. Based on an arithmetic symbolism, the number 53 represents the aspiration to complete knowledge (earthly and divine). The emperor therefore wanted his ideal library to denote, even in the material structure, the possession of universal knowledge