Tahafut_al-Tahafut-transl-Engl-van-den-Bergh

I say:
is the principle of these differences? For the body of the
heavens proceeds from only one and the same simple entity
and the simple can cause only that which is simple of shape,
namely the sphere, and that which is homogeneous, that is,
has no special distinguishable character. And out of this
there is no issue.
‘Simple’ has two meanings: first, simplicity can be attributed to that which
is not composed of many part, although it is composed of form and matter,
and in this way the four elements are called simple;’ secondly, it can be
attributed to that which is not composed of form and matter capable of
changing its form, namely to the heavenly bodies; further, simplicity can
be attributed to the agglomerate which has the same definition for its
whole and its part, even when it is composed of the four elements. The
simple character which is attributed to the heavenly bodies can very well
possess parts which are differentiated by nature, as are the right and left
sides of the sphere and the poles; for the globe, in so far as it is a globe,
must have definite poles and a definite centre through which globes differ
individually, and it does not follow from the fact that the globe has definite
sides that it is not simple, for it is simple in so far as it is not composed of
form and matter in which there is potency, and it is non-homogeneous in
so far as the part which receives the place of the poles cannot be any part
of the globe, but is a part determined by nature in each globe individually.
If this were not so, globes could not have centres by nature through which
they were differentiated; thus they are heterogeneous-in this special
meaning of the word ‘heterogeneous’-but this does not imply that they are
composed of bodies different by nature, nor that their agent is composed
of many potencies, for every globe is one. Nor do the philosophers regard
it as true that every point of whatever globe can be a centre and that only
the agent specifies the points, for this is only true in artificial things, not in
natural globes. And from the assumption that every point of the globe can
be a centre, and that it is the agent which specifies the points, it does not
follow that the agent is a manifold unless one assumes that there is in the
empirical world nothing that can proceed from a single agent; for in the
empirical world things are composed of the ten categories and therefore
anything whatever in the world would need ten agents. But all this, to
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