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

I say:
inside the world, neither continuous with the world nor
separated from it, cannot be understood, because we cannot
understand this according to our human measure; the right
answer is that it is the fault of your imagination, for rational
proof has led the learned to accept its truth. How, then, will
you refute those who say that rational proof has led to
establishing in God a quality the nature of which is to
differentiate between two similar things? And, if the word
‘will’ does not apply, call it by another name, for let us not
quibble about words! We only use the term ‘will’ by
permission of the Divine Law. It may be objected that by its
conventional meaning ‘will’ designates that which has desire,
and God has no desire, but we are concerned here with a
question not of words but of fact. Besides, we do not even
with respect to our human will concede that this cannot be
imagined. Suppose two similar dates in front of a man who
has a strong desire for them, but who is unable to take them
both. Surely he will take one of them through a quality in him
the nature of which is to differentiate between two similar
things. All the distinguishing qualities you have mentioned,
like beauty or nearness or facility in taking, we can assume
to be absent, but still the possibility of the taking remains.
You can choose between two answers: either you merely
say that an equivalence in respect to his desire cannot be
imagined-but this is a silly answer, for to assume it is indeed
possible or you say that if an equivalence is assumed, the
man will remain for ever hungry and perplexed, looking at
the dates without taking one of them, and without a power to
choose or to will, distinct from his desire. And this again is
one of those absurdities which are recognized by the
necessity of thought. Everyone, therefore, who studies, in
the human and the divine, the real working of the act of
choice, must necessarily admit a quality the nature of which
is to differentiate between two similar things.
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