Pythagoras believed that the universe came from chaos and gained a form through moderation and harmony, so he was the first to call it “Cosmos” (the word which in ancient Greek means ornament and order). Nature is less threatening when it is rational. Natural numbers are the building materials of the world. This has led to the belief that everything in the universe, the physical and the metaphysical, the intellectual and the moral, all are built on the distinct model of natural numbers and are fully interpreted through rational relations.
This simple but wonderful concept of the symmetrical structure of the world was soon to be refuted, devastatingly enough for the Pythagoreans.
Today we know that if the stars in the night sky depict natural numbers, the vast blackness behind them depicts the irrationals.
The effort for a rational description of the world expired too early.