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

all things is attachment to matter and being occupied with
matter, and the human soul is occupied by directing matter,
i. e. its body, and when this occupation is terminated and it is
not any longer defiled by the bodily passions and the
despicable conditions which affect it through the things of
nature, all the realities of the intelligibles are revealed to it,
and therefore is it asserted that all the angels know all the
intelligibles without exception, for they too are pure
immaterial intellects.
And having related their theory; Ghazali argues against them:
But we say: If by your assertion that the First does not
exist in matter, you mean that it is not a body, nor impressed
on a body, but exists by itself not comprised by space nor
locally specified by a direction, this is admitted by us. There
remains then your answer to the question what its attribute
is, namely that it is pure intellect-and what do you
understand by ‘intellect’? If you mean by it that which thinks
all the other things, this is just what we are trying to find out
and the point under discussion, and how, therefore, can you
take it as the premiss of a syllogism which must prove it?
And if you mean by it something else, namely that it thinks
its own self-and some of your fellow-philosophers may
concede this to you, but this amounts again to your saying
that what thinks its own self thinks other things also-the
answer to be made is ‘Why do you claim this? For this is not
known by necessity, and only Avicenna of all the
philosophers affirmed it; and how can you claim this as
necessary knowledge, or, if you know it by deduction, what
is your proof? ‘
And if the assertion is made: ‘Because what prevents the
perception of things is matter, and the First is not matter’, we
answer: We concede that matter is an impediment, but we
do not admit that it is the only impediment; and let them
arrange their syllogism in the figure of the hypothetical
syllogism and say: ‘If this First is in matter it cannot think
things, but it is not in matter, therefore it thinks things’. ‘ And
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