ABSTRACT
Plato’s description of the universe, with the earth as the ‘fixed sphere’ at its centre, encircled by each of the planets, had its counterpart in his abstract model of it. In this, the universe was a sphere composed of the 4 elements. To each of these was assigned one of the regular polyhedra, which were conceptualized as being inscribed geometrically in the sphere.1 The atmospheric elements of fire, air, and water are unstable, and are composed of equilateral triangles. Earth, the only stable element, is represented by the cube and all are contained by the sphere of the universe.2 This, it would appear, was the model that John of Damascus, the monk and theologian, had in mind when he wrote in the eighth century,
… we say that in the creation of the universe we consider as heavens that which the pagan philosophers … call a starless sphere. … [Some] say that [its substance] is made from the four elements. Still others say that it is a fifth body and distinct from the four elements. … They say that the heavens have seven spheres. … For they have said that there are seven planets … They also say that the heavens surround the earth like a sphere.
