The Dialectica (Philosophical Chapters)

The Philosophical Chapters — known by its Latin title the Dialectica — is the first part of St. John of Damascus’s Fount of Knowledge: a christened logical and metaphysical toolkit drawn from the Aristotelian-Porphyrian commentary tradition. It defines substance, hypostasis, nature, person, and the predicables as instruments for theology, supplying the precise vocabulary on which his Trinitarian and Christological synthesis depends.

Tradition: Pan-Orthodox (Church Father)

A Philosophical Lexicon for Theology

The Dialectica (Greek Kephalaia philosophika, “Philosophical Chapters”) stands first in the Fount of Knowledge as its propaedeutic (see The Fount of Knowledge). It is, in effect, a philosophical dictionary: a series of short chapters defining and explaining the key terms of logic and metaphysics — being and substance, genus and species, the universal and the particular, nature (physis), essence (ousia), hypostasis, person (prosopon), difference, accident, quality, relation, and the rest. The material is essentially the logic of the Organon as mediated through Porphyry’s Isagoge (the standard late-antique introduction to Aristotle’s Categories) and the Neoplatonic commentary tradition that grew up around it (Louth, St John Damascene, 2002, ch. 3; Roueché, “Byzantine Philosophical Texts of the Seventh Century”). John’s Dialectica belongs to a recognised genre of Christian introductions to logic, popular in the seventh and eighth centuries, written precisely to equip readers to handle the conceptual issues raised by the Christological controversies.

Why a Monk Taught Logic

John is explicit about why a monk of Mar Saba should trouble himself with pagan logic: philosophy is the handmaid of theology. In the opening chapters he rehearses the late-antique definitions of philosophy — philosophy as “knowledge of beings as beings,” as “knowledge of things divine and human,” as “the art of arts and the science of sciences,” and, most tellingly, as “assimilation to God” so far as is possible for man (Dialectica 3; trans. Chase, FOTC 37). His stated purpose is severely practical: theology is conducted in words, and the great heresies — over the Trinity and the person of Christ alike — had turned on the meanings of words such as ousia, physis, and hypostasis. To confess the faith exactly one must first use these terms exactly. The Dialectica therefore clears the ground and forges the instruments before the Exact Exposition expounds the mysteries.

John is careful to insist that he takes from the philosophers only what is true and useful, leaving aside their errors — the gathering, again, of honey from many flowers (cf. the method of synthesis announced in the preface to the whole Fount; trans. Chase, FOTC 37). Reason is a gift of God and the light of the rational soul; rightly disciplined, it serves revelation rather than rivalling it (Louth, St John Damascene, 2002, ch. 3).

Hypostasis and Enhypostaton: Logic in the Service of Christology

The most consequential chapters of the Dialectica are those that fix the meaning of substance / essence (ousia), nature (physis), hypostasis, and person (prosopon), and that introduce the term enhypostaton (“that which exists in another hypostasis,” the in-subsisting). These are not idle philosophical exercises: they are the precise tools John will deploy in Book III of the Exact Exposition to articulate the hypostatic union — the doctrine that Christ’s human nature has no independent hypostasis of its own but subsists in the hypostasis of the Logos (enhypostasia), and that the two natures interpenetrate without confusion (perichoresis). The Dialectica defines the terms; the Christology applies them. This direct feed from logic to doctrine is treated in parallel in 07 — Perichoresis and Enhypostaton. John’s careful distinction of ousia (the common nature) from hypostasis (the concrete particular bearing the nature) is the inheritance of the Cappadocian settlement (see Orthodoxy Guide: The Holy Trinity), here regularised into a teachable lexicon.

Sources: The Alexandrian Commentators

Modern scholarship has shown that the Dialectica is, to a large degree, a careful compilation from the Neoplatonic commentators of the Alexandrian school. John drew, directly or at one remove, on the commentaries of Ammonius Hermeiou (son of Hermeias, c. 440–520) and his pupils and successors — including Philoponus, Elias, and David, and especially Stephanus of Alexandria, through whom John had access to the wider Ammonian tradition (Louth, St John Damascene, 2002, ch. 3; Roueché, “Byzantine Philosophical Texts of the Seventh Century,” Jahrbuch der Österreichischen Byzantinistik 23, 1974, and 29, 1980; cf. Frede on the late-antique commentary tradition). At least several chapters — including the cluster presenting the definitions of philosophy — derive directly from Ammonius’s Commentary on Porphyry’s Isagoge, where the same threefold analysis of those definitions (by object, by purpose, by etymology) is found. John’s originality, here as elsewhere, lies not in inventing the material but in selecting, abbreviating, and ordering it for a specifically Christian and theological end: the Aristotelian-Porphyrian toolkit, baptised and set to work in the service of orthodox confession.

See Also

References

  • John of Damascus. Philosophical Chapters (Dialectica), in Saint John of Damascus: Writings. Translated by Frederic H. Chase, Jr. Fathers of the Church 37. Washington, DC: Catholic University of America Press, 1958.
  • Kotter, Bonifatius, ed. Die Schriften des Johannes von Damaskos I: Institutio elementaris; Capita philosophica (Dialectica). Patristische Texte und Studien 7. Berlin: De Gruyter, 1969.
  • Louth, Andrew. St John Damascene: Tradition and Originality in Byzantine Theology. Oxford Early Christian Studies. Oxford: Oxford University Press, 2002, esp. ch. 3.
  • Roueché, Mossman. “Byzantine Philosophical Texts of the Seventh Century.” Jahrbuch der Österreichischen Byzantinistik 23 (1974): 61–76; and “A Middle Byzantine Handbook of Logic Terminology.” JÖB 29 (1980): 71–98.
  • Porphyry. Isagoge; Ammonius Hermeiou. In Porphyrii Isagogen; Stephanus of Alexandria. Commentaries (Alexandrian commentary tradition underlying the Dialectica).