  The surviving writings are four treatises and ten letters. The four treatises are: 1) On the divine names (DN) (Peri theion onomaton, in Greek; De Divinis Nominibus, in Latin), the longest work of thirteen chapters that deals with affirmative or kataphatic theology, namely, the names attributed to God the creator in scripture and also in pagan texts, but also exploring the limits of language and therefore also involving negative or apophatic theology. 2) On the celestial hierarchy (CH) (Peri tes ouranias hierarchias, in Greek; De coelesti hierarchia, in Latin), a work that examines how the nine choirs of angels (in scripture) are to be understood in lifting us up to God. 3) On the ecclesiastical hierarchy (EH) (Peri tes ekklestiastikes hierarchias, in Greek; De ecclesiastica hierarchia, in Latin) that examines the various orders and liturgy of the church as relating us to God through a divinely appointed but human hierarchy. And 4) On Mystical theology (MT) (Peri mustikes theologias, in Greek; De mystica theologia, in Latin), a brief but powerful work that deals with negative or apophatic theology and in which theology becomes explicitly “mystical” for the first time in history (By mystical here we do not mean an extraordinary or private experience of transcending one’s self in the modern sense of the term, but simply “hidden”. On this see Bouyer, 1949; Vanneste, 1959; McGinn 1994). There follow ten letters that provide helpful comments upon topics in the above four treatises, especially letter 9 on what Dionysius calls symbolic theology of which works 2) and 3) above (CH; EH) form a substantial part. The ten letters appear to be arranged in a roughly hierarchical order, letters 1–4 being addressed to a monk (a certain Gaius, also the name of one or more of St. Paul’s companions), letter 5 to a deacon, letter 6 to a priest, and letters 7 and 9 to hierarchs or bishops. Letter 8 disrupts this order since it is addressed to a monk charged with disrupting the hierarchical order itself!