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

The utmost you can say about the cause is that its
priority to the effect exists by nature, in the way that its
superiority to the effect is a matter of essence and not of
space. But if you do not regard an infinite sequence as
impossible for real temporal priority, it cannot be impossible
for natural essential priority either. But what can the
philosophers mean when they deny the possibility of an
infinite spatial superposition of bodies, but affirm the
possibility of an infinite temporal sequence? Is this theory not
really an inept theory without any foundation?
I say: As to Ghazali's words:
But perhaps for this cause there is another cause and so
on ad infinitum . . . and any method of deductive proof is
forbidden to you, since you admit celestial revolutions
without an initial term: To this difficulty an answer was given
above, when we said that the philosophers do not allow an
infinite causal series, because this would lead to an effect
without a cause, but assert that there is such a series
accidentally from an eternal cause-not, however, in a straight
line, nor simultaneously, nor in infinite matters, but only as a
circular process.
What he says here about Avicenna, that he regarded an infinite number
of souls as possible and that infinity is only impossible in what has a
position, is not true' and no philosopher has said it; indeed, its impossibility
is apparent from their general proof which we mentioned, and no
conclusion can be drawn against them from this assumption of an actual
infinity of souls. Indeed, those who believed that the souls are of a certain
number through the number of bodies and that they are individually
immortal profess to avoid this assumption through the doctrine of the
transmigration of souls.
And as to Ghazali's words:
But what can the philosophers mean when they deny the
possibility of an infinite spatial superposition of bodies, but
affirm the possibility of an infinite temporal sequence?
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