Page 505 - Euclid's Elements of Geometry

ELEMENTS BOOK 13

The Platonic Solids †

† The five regular solids—the cube, tetrahedron (i.e., pyramid), octahedron, icosahedron, and dodecahedron—were problably discovered by
the school of Pythagoras. They are generally termed “Platonic” solids because they feature prominently in Plato’s famous dialogue Timaeus. Many
of the theorems contained in this book—particularly those which pertain to the last two solids—are ascribed to Theaetetus of Athens.

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