Platonic solid

As the names suggest, the groups and their existence are connected to the five Platonic solids. They are in fact the rotation groups of the Platonic solids.

The boat which the gods tell Utnapishtim to build is no ordinary boat but a perfect cube with seven levels; the ark resembles more a Platonic solid from the Timaeus than a seaworthy craft.

The erroneous number of planets, six, gave him^([Johannes Kepler]) the clue for his model of five Platonic solids (the five regular convex polyhedra) on which he erected the universe.

In the 13th and final book, he^([Euclid]) shows how to construct the five Platonic solids, and proves that they are the only regular polyhedra (bodies whose faces are congruent, regular polygons) that exist.