The colloquium calls back to mind Johannes Kepler's attempt to relate the distances between spheres of planets to the five
Platonic bodies. He noted that the cube, tetrahedron,
dodecahedron, icosahedron and octahedron could be fitted in between
the spheres of Copernicus. This coincidence he considered as
a striking proof of the heliocentric hypothesis. Moreover he
proposed to examine the kinematics assumed by Copernicus with
respect to shortcomings responsible for deviations from the
geometric pattern yielded by the platonic bodies. When Kepler,
with the help of his teacher Michael Maestlin, published his
construction in 1597 at Tubingen under the title "Mysterium
Cosmographicum", he was already working at Graz. At that time
he did not know that he would devote the whole of his life to
the examination proposed, which led him to the study of
planetary motion in general. The result was a new form of celestial
kinematics with consequences perhaps more profound than those
of the theory of Copernicus.