Pythagoras taught that all things are number, and that the cosmos is created and governed by numerical principles. In the Pythagorean cosmogenesis, the derivation of the multiplicity of things in the world from an original unity is identical to the derivation of the numbers from the numerical unit, one. Moreover, this identity is made manifest in the mathematical order of the cosmos, as exemplified in the mathematical ratios of the musical scales and the geometrical principles that govern spatial extension. The Pythagoreans saw in all things combinations of eternal principles, such as Limit and Unlimited, One and Many, At Rest and In Motion. This Pythagorean vision, which sees the material world of becoming as imitating the mathematical world of being, provided the seminal insight at the foundation of Western science, both ancient and modern, and continues to manifest its profound influence today.-- Thomas Mcfarlane on Plato's "Parmenides"