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However, Empedocles of Acragas, is best known for having selected all elements as his archai and by the time of Plato, the four Empedoclian elements of were well established.

In the Timaeus, Plato's major cosmological dialogue, the Platonic solid he associated with fire was the tetrahedron which is formed from four triangles and contains the least volume with the greatest surface area.

This also makes fire the element with the smallest number of sides, and Plato regarded it as appropriate for the heat of fire, which he felt is sharp and stabbing, ( like one of the points of a tetrahedra ).