The Bibliotheca (Ancient Greek: Βιβλιοθήκη, Bibliothēkē, "library"), in three books, provides a comprehensive summary of traditional Greek mythology and heroic legends, "the most valuable, whose "stultifying purpose" was neatly expressed in the epigram noted by Patriarch Photios I of Constantinople: The brief and plainly expressed accounts of myth in the Bibliotheca have led some commentators to suggest that even its complete sections are an epitome of a lost work.