Pythagorean astronomical system
An astronomical system positing that the Earth, Moon, Sun, and planets revolve around an unseen "Central Fire" was developed in the fifth century BC and has been attributed to the Pythagorean philosopher Philolaus.
[5] How much of the system was intended to explain observed phenomena and how much was based on myth, mysticism, and religion is disputed.
[4][5] While the departure from traditional reasoning is impressive, other than the inclusion of the five visible planets, very little of the Pythagorean system is based on genuine observation.
[8] Because of questions about the reliability of ancient non-primary documents, scholars are not absolutely certain that Philolaus developed the astronomical system based on the Central Fire, but they do believe that either he, or someone else in the late fifth century BC, created it.
Beginning from the middle, the universe expands outward around a central point, implying a spherical nature.
Additionally, Philolaus reasoned that separated pieces of the Central Fire may have created the heavenly bodies.
By nature the middle is first, and around it dance ten divine bodies—the sky, the planets, then the sun, next the moon, next the earth, next the counterearth, and after all of them the fire of the hearth which holds position at the centre.
[1] According to Eudemus, a pupil of Aristotle, the early Pythagoreans were the first to find the order of the planets visible to the naked eye.
Farther from the Central Fire, the revolution of the planets was slower still, and the outermost "sky" (i.e. stars) probably fixed.
[9] Rather than there being two separate fiery heavenly bodies in this system, Philolaus may have believed that the Sun was a mirror, reflecting the heat and light of the Central Fire.
[15] Johannes Kepler, a sixteenth–seventeenth century European thinker, believed that Philolaus's Central Fire was the sun, but that the Pythagoreans felt the need to hide that teaching from non-believers.
[25] Burch also argues that Aristotle was simply having a joke "at the expense of Pythagorean number theory" and that the true function of the Counter-Earth was to balance Earth.
