Aristotle
(354-322 B.C.)
Aristotle was a famous Greek philosopher, he was a student of Plato.
He studied many sciences including astronomy, to which he contributed
various 'new' ideas in his days.
He wrote a kind of summary of the ideas of the planetary system of the ancient Greece and he added to this his own opinion. Some of his opinions stood firm for more than 2000 years.
The Earth and the planets are spheres.
He believed that the Earth and other planets were spheres, something he based upon what he saw when looking to the Moon. According to him the proof of a spheric Earth was the circularity of her shape on the Moon during eclipses.
Furthermore the ancient Greeks already knew that the stars in sky change location depending on wether the observer moves to the south or the north. Aristotle stated that this was the result of the spheric shape of the Earth.
The Earth is not moving.
He did not believe that the Earth turned around the Sun; in his opinion it was not possible that the Earth was moving, because the stars are fixed in the sky and do not move.
In his planetary system he placed the Sun and Moon nearer to the Earth than the planets, the reason for this was that he had observed himself that the light of Mars was blocked by the Moon, and that he was familair with the fact that the Egyptians and Babylonians had observed this also.