9781422283356

450 bce , put these ideas together and said that all things were a mixture of air, earth, fire and water. Empedocles is credited as being the first to suggest, after examining a meteor , that the Earth and stars are made from the same materials. THE MUSIC OF THE SPHERES One of the greatest Greek thinkers was Plato. His ideas influenced thought long after his death. Plato was born in Athens around 427 bce . He declared that the heavens were perfect and so the stars and planets must move in “perfect curves on perfect solids,” circles around spheres, in other words. He believed that the spheres made music as they turned, an idea that persisted for many centuries. However, Plato’s celestial spheres did not fit what most people actually observed. Sometimes the planets did funny things; they looped backwards in their paths before turning back and carrying on in the first direction again. How was this to be explained? The Greeks were reluctant to give up what seemed a good idea. The astronomer Eudoxus came up with a complex scheme that involved spheres moving within spheres within yet more spheres, all rotating in slightly different directions.

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