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

difference in the directions of their movements forms the specific
differentia of their species is something proper to them. Imagine the first
heaven as one identical animal whose nature obliges it-either by necessity
or because it is for the best-to move with all its parts in one movement
from east to west. The other spheres are obliged by their nature to have
the opposite movement. The direction which the body of the universe is
compelled to follow through its nature is the best one, because its body is
the best of bodies and the best among the moving bodies must also have
the best direction. All this is explained here in this tentative way, but is
proved apodictically in its proper place. This is also the manifest sense of
the Divine Words, ‘There is no changing the words of God’, and ‘There is
no altering the creation of God’. If you want to be an educated man,
proceeding by proof, you should look for the proof of this in its proper
place.
Now if you have understood all this, it will not be difficult for you to see
the faults in Ghazali’s arguments here about the equivalence of the two
opposite movements in relation to each heavenly body and to the
sublunary world. On first thoughts it might be imagined that the movement
from east to west might also belong to other spheres besides the first, and
that the first sphere might equally well move from west to east. You might
as well say that the crab could be imagined as having the same direction
of movement as man. But, as a matter of fact, such a thought will not
occur to you about men and crabs, because of their difference in shape,
whereas it might occur to you about the heavenly spheres, since they
agree in shape. He who contemplates a product of art does not perceive
its wisdom if he does not perceive the wisdom of the intention embodied in
it, and the effect intended. And if he does not understand its wisdom, he
may well imagine that this object might have any form, any quantity, any
configuration of its parts, and any composition whatever. This is the case
with the theologians in regard to the body of the heavens, but all such
opinions are superficial. He who has such beliefs about products of art
understands neither the work nor the artist, and this holds also in respect
of the works of God’s creation. Understand this principle, and do not judge
the works of God’s creation hastily and superficially-so that you may not
become one of those about whom the Qur’an says: ‘Say, shall we inform
you of those who lose most by their works, those who erred in their
endeavour after the life of this world and who think they are doing good
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