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

I say:
and possible at another?’ If you say: ‘The times are similar,’
the answer is: ‘But so are the measures, and why should
one measure be possible and another, bigger or smaller by
the width of a nail, impossible?’ And if the latter assumption
is not impossible, the former is not impossible either.’ And
this is the way to oppose them.
But the true answer is that their supposition of
possibilities makes no sense whatever. We concede only
that God is eternal and powerful, and that His action never
fails, even if He should wish it. And there is nothing in this
power that demands the assumption of a temporal
extension, unless imagination, confusing God’s power with
other things, connects it with time.
The summary of this is that the Ash’arites say to the philosophers: this
question whether the world could be larger or smaller is impossible
according to us; it has sense only for the man who believes in a priority of
possibility in relation to the actualization of a thing, i.e. the realization of
the possible. We, the Ash’arites, however, say: ‘Possibility occurs together
with the actuality as it is, without adding or subtracting anything.’
Now my answer is that he who denies the possibility of the possible
before its existence denies the necessary, for the possible is the contrary
of the impossible without there existing a middle term, and, if a thing is not
possible before its existence, then it is necessarily impossible.’ Now to
posit the impossible as existing is an impossible falsehood, but to posit the
possible as existing is a possible, not an impossible, falsehood.’ Their
assertion that possibility and actuality exist together is a falsehood, for
possibility and actuality are contradictory, and do not exist together in one
and the same moment. The necessary consequence for them is that
possibility exists neither at the same time as the actuality nor before it.
The true consequence for the Ash’arites in this discussion is not that the
eternal passes from impotence to power, for he who cannot do an
impossible act is not called impotent, but that a thing can pass from the
nature of the i impossible to the nature of existence, and this is like the
changing of the necessary into the possible. To posit a thing, however, as
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