Reality, like a lightning bolt, illuminates a landscape of eternal Forms, constants that are the mind of Nature, the living Cosmos and its choir of beings; love, consciousness and number. The perennial philosophy, already ancient in the time of Pythagoras, asserts that these principles are themselves the wake of a singular phenomenon, the indivisible source we name Unity, the original quality, without quantity or definition. To study number is to study Unity, and the archaic curriculum frames this pursuit through the qualitative behaviour of numbers in relation to each other as the arts of Arithmetic, Geometry and Harmonics. Fragments of this original science, scattered through the ruins of ancient sites, traditional craft methods and surviving early texts of philosophy and mathematics, show the central position occupied by Harmony, the comparison or synthesis of fractioned parts. Yet, as these sciences passed from Egypt to ancient Greece, their symbolic roots were lost in the labyrinths of time and the means to integrate them as a single study was obscured. The quest to rediscover this fusion of the number arts led to the harmonic-geometric work of Johannes Kepler, and the geometric- harmonic equal-tempered scale, although the alchemical solution of the philosophers remained elusive. And yet, from the Diagram drawn in a humble square a living gesture of Universal Harmony is revealed, illuminating the intentions and goals of ancient societies across the planet, recalling its status accorded by Socrates: the Highest Good.