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

suppose its agent to act like an agent in the empirical world, for the
empirical agent changes one quality in the existent into another; it does
not change absolute nonexistence into existence-no, it brings the existent
into a form and an intelligible quality through which this existent becomes
another existent instead of this, different from it in substance, definition,
name, and act, as it is expressed in the Divine Words: ‘We have created
man from [an extract of] clay, then we made him a clot in a sure
depository, then we created the clot congealed blood, and we created the
congealed blood a morsel, etc. It is for this reason that the ancient
philosophers believed that the absolute existent neither comes into
existence nor can be destroyed.
Now, if one concedes to the theologians that the heavens were created
in time, they are unable to prove that they are the first of created things, as
is the evident meaning of what is said in the Venerable Book in more than
one verse, for instance, in the Divine Words, ‘Do not those who misbelieve
see that the heavens and the earth were both solid, &c.?’ and in the
words, ‘and His throne was upon the water’ and in the words, ‘then He
made for heaven and it was but smoke, &c.’s And as concerns this agent,
according to the theologians, it creates the matter and the form of that
which becomes, if they believe that it has a matter, or it creates the thing
in its totality, if they believe it to be simple in the way they believe the atom
to be simple; and if this is so, this kind of agent changes either nonexistence
into existence, namely, when there is generation, that is when
the atom, which according to them is the element of the bodies, comes
into being; or existence into non-existence, namely, when there is
destruction, that is, when the atom is destroyed. But it is clear that an
opposite cannot be changed into its opposite, and that non-existence itself
cannot become existence nor warmth itself cold. It is the privation which
becomes existent, it is the warm thing which becomes cold and the cold
thing which becomes warm, and for this reason the Mu’tazilites say that
privation is an entity although they deprive this entity of the attribute of
existence before the becoming of the world. And their arguments by which
they believe it can be proved that a thing does not come into being from
another thing are incorrect. The most plausible of them is their affirmation
that, if a thing came into being from another thing, this would imply an
infinite regress. The answer is that this is only impossible for production in
a straight line, which, indeed, needs an infinite existence in act; but, as to
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