In the Timaeus , his major cosmological dialogue , the Platonic solid associated with air is the octahedron which is formed from eight equilateral triangles .
Plato ( 427 -- 347 BCE ) took over the four elements of Empedocles .
In the Timaeus , Plato 's major cosmological dialogue , the Platonic solid associated with air is the octahedron which is formed from eight equilateral triangles .
Plato ( 427 -- 347 BCE ) took over the four elements of Empedocles .