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

nothingness; no, non-existence, according to them, occurs when the form
of the thing that becomes non-existent disappears, and the opposite form
appears. Therefore the following objection which Ghazali makes is valid.
Ghazali says:
I say:
This is wrong for two reasons. The first is: Does the
occurrence of whiteness imply the absence of blackness? If
they deny it, this is an affront to reason, and if they admit it, it
may be asked: Is what is implied identical with that which
implies? To admit this is a contradiction, for a thing does not
imply itself, and if they deny it, it may be asked: Has that
which is implied an intelligible meaning? If they deny it, we
ask, `How do you know, then, that it is implied, for the
judgement that it is implied presupposes that it has a
sensible meaning?’ If they admit this, we ask; `Is this thing
which is implied and has a sensible meaning, i.e. the
absence of blackness, eternal or temporal?’ The answer
`eternal’ is impossible; if they answer `temporal’, how should
what is described as occurring temporally not be clearly
understood? And if they answer `neither eternal nor
temporal, this is absurd, for if it were said before the
occurrence of whiteness that blackness was non-existent, it
would be false, whereas afterwards it would be true.’ It
occurred, therefore, without any doubt, and this occurrence
is perfectly intelligible and must be related to the
Omnipotent.
This is an occurrence which is perfectly intelligible and must be related
to the Omnipotent, but only accidentally and not essentially, for the act of
the agent does not attach itself to absolute non-existence, nor to the nonexistence
of anything, for even the Omnipotent cannot bring it about that
existence should become identical with nonexistence. The man who does
not assume matter cannot be freed from this difficulty, and he will have to
admit that the act of the agent is attached to non-existence primarily and
essentially. All this is clear, and there is no need to say more about it. The
philosophers, therefore, say that the essential principles of transitory
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