Iamblichus of Chalcis

Extended Version*

© 2003, Bruce J. MacLennan


It used to be fashionable to dismiss Iamblichus as representing the final decadence of classical Greek philosophy, but in recent decades we have come to appreciate him for his revitalization of Platonic philosophy in the fourth century CE and as a critical link in the transmission of Platonic ideas into the Middle Ages, Renaissance, and modern world. This reassessment is partly a result of our own improved understanding of the role and function of ancient philosophy. But first, some biographical background.

Iamblichis lived from about 245 to about 325. He was born in Chalcis (modern Qinnesrin) in north Syria, an intellectually lively city in a prosperous region, which had been at peace for over 200 years (although the Persians under Sapor invaded in 256). He became a student of Porphyry and probably studied with him in Rome or Sicily. Although they came to differ on many philosophical points, there is no reason to suppose that they did not respect each other.

Eventually, perhaps around 305, Iamblichus returned to Syria to found his own school at Apameia (near Antioch), a city already famous for its Neoplatonic philosophers. Among the philosophers he trained was Aedesius (died c.355), himself the teacher of Maximus of Ephesus (died 370), who in turn initiated the Emperor Julian (331-363) into the mysteries of Neoplatonism and encouraged him in his doomed attempt to revitalize paganism in the face of spreading Christianity.

At a time when most wealthy families chose Greek names, Iamblichus chose to retain his Semitic name, perhaps to honor his noble ancestors, who included several priest-kings of Emesa. This choice was consistent with his general view of Greek culture for, like Plato (Laws 657a), he felt that the Greeks changed ancient traditions too capriciously and had too little respect for the "old nations":

For the Greeks are naturally followers of novelty and are carried off everywhere by their volatility, neither possessing any stability themselves, nor preserving what they have received from others, but rapidly abandoning this, they transform everything through an unstable desire of seeking something new. (Iamblichus, DM VII.5)

Therefore, in his philosophy, Iamblichus tried to harmonize the rational discourse of classical Greek philosophy with the ancient religious practices of Egypt, Assyria, and Chaldaea.


Iamblichus wrote a great deal, but much of it has been lost. He also established the definitive Neoplatonic curriculum, which was followed for the next two centuries. The first part was his own Collection of Pythagorean Doctrines in ten books, a compendium of extracts from ancient philosophers. (Only the first four books, and perhaps fragments of the fifth, survive.) The next subject was the works of Plato and Aristotle, for which Iamblichus wrote a number of commentaries (only fragments survive). In particular, he set down the order in which the Platonic dialogues should be studied and defined principles for their allegorical interpretation (later applied to Christian exegesis). Study of each dialogue was supposed to effect a specific transformation in the student's soul.

With his emphasis on respect for ancient wisdom, he treated Plato's dialogues as divinely inspired scripture. He also accorded great respect to the Chaldean Oracles, a collection of inspired verses dating to perhaps the second century CE. He devoted at least 28 books to their interpretation and taught their doctrine of theurgy, explained below.

Neoplatonic Philosophy

Like other Neoplatonists, Iamblichus explained reality as a hierarchical emanation into multiplicity from an Ineffable One. Within the Ineffable One are two opposed principles, Limit and the Unlimited (or the One and the Many), the mixture of which generates the levels of reality. The One is the ultimate principle of Limit, whereas the multiplicity of pure, unformed, chaotic Matter is the ultimate expression of the Unlimited. The emanation proceeds through the Forms, the ultimate, eternal principles of all things, to the World Soul, which unites the Forms with Matter and thereby imparts order to the cosmos. The individual soul is a microcosm, that is, an image in miniature of the cosmos.

Love or Desire, conceived as a cosmic force (the active power of unity) and a deity (firstborn of the One), is essential to the structure of reality, for it coordinates the Forms and draws multiplicity into a cosmic unity. The One "inserts, by union, the indissoluble principle of love, which retains and preserves both things that are in existence and such as are coming into being" (DM IV.12), "an affection that connectedly contains all things, producing this bond through a certain ineffable communion" (DM V.10). Further, it is necessary for the One to proceed outward into matter - and for individual souls to become embodied - for otherwise desire could not manifest: there can be no desire without an "other" to be desired. Thus, by means of embodied souls, the One loves and desires itself, and so binds the cosmos in unity.

Therefore, unlike the Gnostics and some other Neoplatonists, Iamblichus did not consider matter to be evil or the embodied soul to be "fallen." Rather, humans have an essential role in the creation and providential ordering of the cosmos. They fulfill this role best through the practice of theurgy.


"Theurgy," which may be translated "god-work," refers to practices (rituals) directed toward the gods, in contrast to theology (god-talk), which is rational discourse about the gods. It also refers to the subsequent action of the gods by which they transform the theurgist, for it aims at "purification, liberation, and salvation of the soul" (DM X.5, 7). The theoretical basis for theurgy is described in one of Iamblichus' surviving works, The Reply of the Master Abammon to "Porphyry's Letter to Anebo," better known as On the Mysteries of the Egyptians; it is a systematic reply to a number of objections raised by Porphyry against the practice of theurgy.

Theurgy is based on the idea that, since the Demiurge, the Platonic creator god, has organized matter in accord with the eternal Forms, therefore, material objects reveal the Forms and can be used as a means for the soul to realign itself with Providence and to unify itself with divinity. In particular, a theurgic rite makes use of certain symbols (signs, tokens), which the gods have imprinted with the Forms. For example, the heliotrope is a symbol for the sun because it turns toward it, as is the cock because it heralds the rising sun. Likewise, the sun, as source of light and life, governing our cosmos, points toward the Ineffable One. Similarly, the Demiurge has placed symbols within each embodied soul, but most people are unconscious of them.

Through emanation a unified, eternal Form is scattered into multiplicity in space and time. The theurgist attempts to restore the unity of the Form by reassembling its symbols: materials, objects, images, shapes, sounds (invocations, hymns), and so forth. In this way the theurgist creates a suitable receptacle for the god. In addition, these external symbols awaken the symbols in the theurgist's soul, which bring it into alignment with the god.

Although Form proceeds from its essence into matter, by theurgy the embodied soul returns to its essence. Furthermore, the love or affinity that draws together all a god's symbols also draws the god and theurgist closer together. Therefore love, which has proceeded outward into the world, is redirected by the theurgist back towards its source. Thus the theurgist completes the erotic circuit that binds the universe into a whole.


Iamblichus' philosophy and theurgy were very influential on later Neoplatonists, such as Proclus (c.410-485). From Proclus, in turn, perhaps by way of Damascius (fl. c.529), these ideas passed to pseudo-Dionysius the Areopagite (sixth century?), whose works laid the foundation of the Christian mystical tradition. Theurgy was rediscovered by Marsilio Ficino (1433-99), whose Platonic Academy helped engender the Italian Renaissance. More recently, Iamblichus' ideas have influenced the psychological theories and practices of C. G. Jung (1875-1961) and his followers.


Clarke, Emma C., Iamblichus' De Mysteriis: A Manifesto of the Miraculous. Aldershot, England: Ashgate, 2001.

Dillon, John M., Iamblichi Chalcidensis in Platonis Dialogos Commentariorum Fragmenta. Leiden: E. J. Brill, 1973. The introduction is an excellent overview of his life, works, and philosophy.

Fowden, Garth, The Egyptian Hermes: A Historical Approach to the Late Pagan Mind, rev. ed. Princeton: Princeton University Press, 1993. Chs. 5 & 6 are especially relevant to Iamblichus and theurgy.

Iamblichus, Iamblichus On the Mysteries and Life of Pythagoras. Transl. Taylor, Vol. XVII of the Thomas Taylor Series. Somerset: Prometheus Trust, 1999. Classic 19th century translation.

Iamblichus, On the Mysteries of the Egyptians: The Reply of the Master Abamon to the Letter of Porphyry to Anebo. Text, translation and notes by Clarke, E.C., Dillon, J.M., & Hershbell, J. Atlanta: Scholars, 2003. The newest translation.

Shaw, Gregory, Theurgy and the Soul: The Neoplatonism of Iamblichus. University Park: Pennsylvania State University Press, 1995.

* Extended version of article in Meet the Philosophers of Greece, ed. Patricia O'Grady, Aldershot: Ashgate, 2005..