When they had mastered the understanding of the Heavens (including the process by which the Sun is destroyed, each evening, after it sets), the Geomancers turned their eyes to this world. They began to, largely, concern themselves with the intersection of lines. They probed the meaning hidden in the Angle, the Surface and the Solid. (They created that word for the ratio of a circle to its periphery.) And, for some time, they paid particular note to the Hyperbole, Parabola and the Ellipse. Yet, in time, they stumbled upon (some call this chance, others prefer destiny), the four-sided Polygon. They understood this to represent the conceptual unit of a quantum of energy. They called it the Basic Structural Unit of the Universe and came to believe that all entities formed by the intersection of vectors could consist of no material other than the mathematics that they had devised. And it was a thousand years after the death of the last Geomancer before this, too, would crumble into dust (though remnants are said to exist in those places yet untouched by the hand of Man).