the case that those on this side were beneath those on the other, or that those on the other side were beneath them. Likewise, the celestial spheres encompass the centre, yet neither side of a sphere is beneath the other, nor is the northern pole beneath the southern pole, or vice versa. The northern pole is, however, the one visible to us above the earth, and its altitude depends on people’s distance from the equator. For someone thirty degrees from the equator, for example, the pole’s altitude is thirty degrees. This is what is called the latitude of a locality.
Just as the sides all around the earth and the rounded sides of the celestial sphere are not above or below one another, so too the living creatures, plants, and heavy objects upon the earth cannot be said to be beneath those on the other side. This is merely something a person imagines, involving a relative sense of “below.” Consider an ant walking beneath a ceiling: the ceiling is above it even though its feet face the ceiling. Likewise, someone suspended upside down remains beneath the sky even though their feet point towards it. Similarly, a person on one side of the earth or the celestial sphere imagines that the other side is beneath them. No two people who hold that the celestial spheres are spherical disagree on this matter.
The spherical form of the celestial spheres is not only the position of astronomers and mathematicians; it is also the position of Muslim scholars. Abū al-Hasan ibn al-Munādī, Abū Muhammad ibn Hazm, Abū al-Faraj ibn al-Jawzī, and others have stated that Muslim scholars agree on this. And He has said