The Ideas
Prisca theologia
Prisca theologia ("ancient theology") is the Renaissance idea that God gave one true theology to remote antiquity, handed down through a chain of sages — Hermes Trismegistus near its head — and flowing into Plato and Christianity. It rested on a wrong chronology, demolished philologically by Isaac Casaubon in 1614.
In 1463 Cosimo de’ Medici told Marsilio Ficino to pause translating Plato and translate Hermes first. That decision only makes sense inside one big idea: prisca theologia, the “ancient theology”.
The idea
God, the theory ran, gave a single true theology to remote antiquity, transmitted through a genealogy of sages — in Ficino’s chain: Zoroaster, Hermes Trismegistus, Orpheus, Aglaophemus, Pythagoras, Plato. Since Hermes was believed older than Plato and near-contemporary with Moses, the Corpus Hermeticum seemed to anticipate Genesis and the Gospel of John. The claim had patristic cover: Lactantius treated Hermes as an ancient gentile prophet of Christ; Augustine accepted his antiquity while condemning the idolatry of the Asclepius. Crucially, the Renaissance version was an attempt to prove Christianity’s truth, not an alternative to it.
The demolition
In 1614 Isaac Casaubon showed on philological grounds — post-classical Greek vocabulary, anachronisms, echoes of Plato and Christian idiom — that the Corpus is a product of the early Roman imperial era, not primeval Egypt. It is a landmark of historical criticism. It did not, however, kill Hermes: post-1614 Hermetic currents flourished, and Athanasius Kircher simply ignored the redating.
Traps
Keep two terms apart: prisca theologia locates truth in the deep past, degenerating over time; the related philosophia perennis holds truth to be always and everywhere available. Popular writing conflates them constantly. And any site claiming the Corpus Hermeticum is “5,000 years old” is repeating a Renaissance error refuted in 1614 — though the honest nuance is that the late texts do preserve older, genuinely Egyptian traditions.
Why it matters
Prisca theologia explains why Hermeticism mattered so enormously to the Renaissance — and why its history is a story about chronology. One dating error powered two centuries of Christian Hermetism; one philological fact-check founded modern source criticism.
Fair questions
What does prisca theologia mean?
Latin for 'ancient theology': the idea that God gave one true theology to remote antiquity, passed down through sages — Zoroaster, Hermes, Orpheus, Pythagoras, Plato in Ficino's chain — and harmonizing with Christianity.
How is it different from philosophia perennis?
Prisca theologia locates truth in the deep past, degenerating over time; philosophia perennis holds truth is always available everywhere. The Renaissance worked with the first; modern perennialism recycles the second — they are often conflated.
Who disproved the antiquity of Hermes?
Isaac Casaubon, in 1614, using philological evidence — post-classical vocabulary and anachronisms — dated the Corpus Hermeticum to the early Roman imperial era. Many occult writers simply ignored him.
Sources & further reading
- Copenhaver, Hermetica (1992), introduction.
- Ebeling, The Secret History of Hermes Trismegistus (2007).
- Research dossiers: ideas-glossary.md §6; renaissance.md §2.
Where the story starts → What is Hermeticism?