Liber de Causis

The Liber de Causis (Book of Causes) is an anonymous Arabic adaptation of Proclus's Elements of Theology, composed in Baghdad c. 850 CE. It was translated into Latin in Toledo c. 1187 by Gerard of Cremona and circulated throughout medieval Europe under the false attribution to Aristotle.

Hermetic Reception

Thomas Aquinas identified its true Proclean origins in his commentary (c. 1272), but by then the text had already deeply shaped medieval scholastic metaphysics. It provided the emanationist framework — the procession of intelligences from the First Cause — that made the Hermetic cosmology of the Corpus Hermeticum immediately comprehensible to Latin readers when Ficino translated it in 1463. The Liber de Causis forms a conceptual triad with the Liber XXIV Philosophorum and De sex rerum principiis: the first gives the definition of God (infinite sphere), the second gives the causal procession (First Cause → intelligences), and the third gives the formal principles of created being.