A couple of additional curious properties of the Platonic solids and their faces and vertices:
The
icosahedron has 20 faces and 12 vertices.
The
dodecahedron has 12 faces and 20 vertices.
The
octahedron has 8 faces and 6 vertices.
The
cube has 6 faces and 8 vertices.
The
tetrahedron has 4 faces and 4 vertices.
Each of the pairs above are dual polyhedra, i.e. if one connects the centers of each face of one polyhedron, the other polyhedron of the pair results. Doing this with a tetrahedron yields another tetrahedron.
Imagine a line drawn from any vertex to the center of the solid. If you were to 'slice off' the vertex on a plane perpendicular to the imagined line, without slicing past any of the other vertices, the new face would be the shape of a face of the next solid 'down' in the sequence.
The triangle-faced
icosahedron would yield a
pentagon.
The pentagon-faced
dodecahedron would yield a
triangle.
The triangle-faced
octahedron would yield a
square.
The square-faced
cube would yield a triangle.
The triangle-faced
tetrahedron, oddball that it is, would yield a triangle, since it is the last in the line and
sufficient unto itself.
Plato associated the tetrahedron, cube, octahedron and icosahedron with fire, earth, air, and water. He linked the dodecahedron with the universe in its entirety, as that "which god used for embroidering the constellations on the whole heaven." Plato's followers were not comfortable with the disjunction between the four elements and the five solids. Aristotle proposed a fifth element (quintessence), the aether (to associate with the dodecahedron) which filled the cosmos and
served as a medium for change and motion (this idea held, in various forms, until the Michelson Morley Experiment in 1887.)
Plato also had a system for explaining the interactions between the four elements by performing various arithmetical operations using the number of faces of the associated solids. For example, heating water produces two 'particles' of air and one of fire, or 20= (2x8)+4 (1 icosahedron=2 octahedra + 1 tetrahedron). Considering that water is H2O, this particular example is oddly prescient.
Information about association of solids with elements from: The Golden Ratio, Mario Livio, Broadway Books, 2002