"Let no one destitute of geometry enter my doors."
Plato was a Classical Greek philosopher,mathematician, writer of philosophical dialogues, and founder of the Academy in Athens, the first institution of higher learning in the Western world. Along with his mentor, Socrates, and his student, Aristotle, Plato helped to lay the foundations of Western philosophy and science. Plato was originally a student of Socrates, and was as much influenced by his thinking as by his apparently unjust execution.
The so-called Platonic Solids are regular Polyhedra. Polyhedra is a Greek word meaning many faces. There are five of these, and they are characterized by the fact that each face is a regular polygon, that is, a straight-sided figure with equal sides and equal angles:
Plato associates four of the Platonic Solid with the four elements. He writes: We must proceed to distribute the figures [the solids] we have just described between fire, earth, water, and air... Let us assign the Cube to earth, for it is the most immobile of the four bodies and most retentive of shape the least mobile of the remaining figures (Icosahedron) to water the most mobile (Tetrahedron) to fire the intermediate (Octahedron) to air Note that earth is associated with the cube, with its six square faces. This lent support to the notion of the foursquaredness of the earth.