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

do not know of any one who makes a distinction here between the spatial
and the non-spatial, with the single exception of Avicenna. I do not know
of any other philosopher who affirms this, it does not correspond with any
of their principles and it makes no sense, for the philosophers deny the
existence of an actual infinite equally for material and for immaterial
things, as it would imply that one infinite could be greater than another.
Perhaps Avicenna wanted only to satisfy the masses, telling them what
they were accustomed to hear about the soul. But this theory is far from
satisfactory. For if there were an actual infinite and it were divided in two,
the part would equal the whole; e.g. if there were a line or a number
actually infinite in both directions and it were divided in two, both the parts
and the whole would be actually infinite; and this is absurd. All this is
simply the consequence of the admission of an actual and not potential
infinite.
Ghazali says:
If it is said, ‘The truth lies with Plato’s theory of one
eternal soul which is only divided in bodies and returns after
its separation from them to its original unity’, we answer:
This theory is still worse, more objectionable and more apt to
be regarded as contrary to the necessity of thought. For we
say that the soul of Zaid is either identical with the soul of
Amr or different from it; but their identity would mean
something absurd, for everyone is conscious of his own
identity and knows that he is not another, and, were they
identical, their knowledge, which is an essential quality of
their souls and enters into all the relations into which their
souls enter, would be identical too. If you say their soul is
unique and only divided through its association with bodies,
we answer that the division of a unity which has no
measurable volume is absurd by the necessity of thought.
And how could the one become two, and indeed a thousand,
and then return to its unity? This can be understood of things
which have volume and quantity, like the water of the sea
which is distributed into brooks and rivers and flows then
back again into the sea, but how can that which has no
quantity be divided? We seek to show by all this that the
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