philosophia perennis

Latin, the perennial philosophy. According to Aldous Huxley ‘the phrase was coined by Leibniz; but the thing—the metaphysic that recognizes a divine Reality substantial to the world of things and lives and minds; the psychology that finds in the soul something similar to, or even identical with, divine Reality; the ethic that places man's final end in the knowledge of the immanent and transcendent Ground of all being—the thing is immemorial and universal’. In fact the phrase is older than Leibniz, being the title of a book published in 1540. Huxley use the notion to promote the idea of a universal, deep, and revealing mystical experience.