“But it is better to assume principles less in number and finite, as Empedocles makes them to be. All philosophers... make principles to be contraries... (for Parmenides makes principles to be hot and cold, and these he demominates fire and earth) as those who introduce as principles the rare and the dense. But Democritus makes the principles to be the solid and the void; of which the former, he says, has the relation of being, and the latter of non”