14. Smaller Spheres

Yesodei HaTorah 3:3

The spheres possess no weight and no color. They appear to us as blue because of the atmosphere. Similarly, the spheres have no taste and no smell. These phenomena only exist in the physical things that the spheres contain.

Yesodei HaTorah 3:4

All the spheres that surround the world are round and Earth is suspended in the middle of them. Some of the planets have their own small spheres that do not include the Earth. Small spheres that do not surround the Earth are fixed inside larger spheres that do.

Editor’s note: I am not able to explain the Rambam’s astronomy. In Hilchos Kiddush HaChodesh (17:24), he says that it is based on the science of Greek astronomers. In Moreh Nevuchim, he is willing to disregard Talmudic dicta (3:14) and even Biblical verses (2:25) in favor of observable science when necessary. Readers are free to assume either that the Rambam was sharing the best science of his day, or that he is describing spiritual rather than physical phenomena.