"[I]t does not follow that because heaven moves in a circle that the earth or something else rests at its center... because circular movement... does not require... any body at rest at the center... [I]t is possible to imagine that the earth moves with heaven in its daily movement... [A]ssuming that the earth moves with or contrariwise to heaven, it does not follow... that celestial movement would stop; so... this circular movement of heaven does not require that the earth should remain motionless at the center of the world. ...[I]t is not impossible that the whole earth moves, with a different movement or in another way... For otherwise the parts near the center would never reach the place where they are destroyed and would be perpetual... Against this objection and against the principal argument is the manifest evidence of heaven itself, for to save appearances and from our observations of celestial movements... there are spherical bodies called epicycles in heaven, and that each epicycle has its own proper circular movement about its center... different from the... heavenly sphere... [I]t is impossible... that any body should be at rest in the center of this epicycle."