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

All their proofs where this problem is concerned are
imaginary. Further, they are not able to reduce all the
qualities which they admit to the essence itself, for they
assert, that it is knowing, and so they are forced to admit that
this is something additional to its mere existence, and then
one can ask them: `Do you concede that the First knows
something besides its essence?’ Some of them concede
this, whereas others affirm that it only knows its own self.
The former position is that taken by Avicenna, for he affirms
that the First knows all things in a universal timeless way,
but that it does not know individuals, because to
comprehend their continual becoming would imply a change
in the essence of the knower. z But, we ask, is the
knowledge which the First has of all the infinite number of
species and genera identical with its self-knowledge or not?
If you answer in the negative, you have affirmed a plurality
and have contradicted your own principle; if you answer in
the affirmative, you are like a man claiming that man’s
knowledge of other things is identical with his self-knowledge
and with his own essence, and such a statement is mere
stupidity. And it may be argued: `The definition of an
identical thing is that its negation and affirmation cannot be
imagined at the same time, and the knowledge of an
identical thing, when it is an identical thing, cannot at the
same time be imagined as existing and not existing. And
since it is not impossible to imagine a man’s self-knowledge
without imagining his knowledge of something else, it may
be said that his knowledge of something else is different
from his self-knowledge, since, if they were the same, the
affirmation or negation of the one would imply the affirmation
or negation of the other. For it is impossible that Zaid should
be at one and the same time both existing and not existing,
but the existence of self-knowledge simultaneously with the
non-existence of the knowledge of something else is not
impossible, nor is this impossible with the self-knowledge of
the First and its knowledge of something else, for the
existence of the one can be imagined without the other and
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