platonic solids
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Platonic Solids © Kristen A. Treglia
2007
They were named such because they were known at the time of Plato
(circa 427-347 BC)
"Let early education be a sort of amusement.
You will then be better able to find out the natural bent."
~Plato
What are they?
• Convex polyhedra with equivalent faces composed of congruent convex regular polygons
• Polyhedra: closed solid figure, consisting of four or more planar faces, pairs of which meet at the edges. At least 3 faces must meet at the vertices.
The word polyhedron
comes from the
Greek poly (many) and
the Indo-European
hedron (seat).
Euler Polyhedron Formula
F – E + V = 2
Polyhedra
In Timaeus,
Plato named all five and drew a direct connection between the platonic solids and the elements of:
TetrahedronFire
CubeEarth
OctahedronAir
IcosahedronWater
DodecahedronThe Universe
Links
• YouTube
• del.icio.us/krillion/geometry
• Notes on page 3 of this presentation
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