After failing to find a unique arrangement of polygons that fit known astronomical observations (even with extra planets added to the system), Kepler began experimenting with 3-dimensional polyhedra.
Nakon što nije uspio pronaći jedinstveno uređenje poligona koji odgovaraju poznatim astronomskim promatranjima (čak s pomoćnim, nepostojećim planetima dodanim u sustav), Kepler je počeo eksperimentirati s 3-dimenzionalnim poliedrima.