Lumen naturale
Lumen naturale
Natural light, equivalent to lumen naturalis rationis, in medieval philosophy and theology denoted the ordinary cognitive powers of human reason unaided by the supernatural light of grace, lumen gratiae, or divine revelation, lumen fidei. — J.J.R.
The phrase “natural light of reason” occurs also in the scientific writings of Galileo (q.v.) and Descartes (q.v.) — P.P.W.