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

eternity of the world. Plato himself believed in the temporal creation of the
world not by God Himself but by a demiurge. But later followers of Plato
differed from him on this point. Amongst the post-Aristotelian schools only
the Stoics assumed a periodical generation and destruction of the world.
Theophrastus had already tried to refute some of the Stoic arguments for
this view, and it may well be that John Philoponus made use of some
Stoic sources for his defence of the temporality of the world.
The book by Proclus is lost, but John Philoponus, who as a Christian
believes in the creation of the world, gives, before refuting them, the
arguments given by Proclus. The book by Philoponus was translated into
Arabic and many of its arguments are reproduced in the Muslim
controversies about the problem (arguments for the temporal creation of
the world were also given by Philoponus in a work against Aristotle’s
theory of the eternity of the world, arguments which are known to us
through their quotation and refutation by Simplicius in his commentary on
Physics viii; one of these arguments by Philoponus was well known to the
Arabs and is also reproduced by Ghazali, see note 3. 3). The argument I
have mentioned is the third as given by Proclus. Philoponus’ book is
extremely important for all medieval philosophy, but it has never been
translated into a modern language and has never been properly studied.
On the whole the importance of the commentators of Aristotle for Arabic
and medieval philosophy in general has not yet been sufficiently
acknowledged.
To this argument Ghazali gives the following answer, which has become
the classic reply for this difficulty and which has been taken from
Philoponus. One must distinguish, says Philoponus, between God’s
eternally willing something and the eternity of the object of His Will, or, as
St. Thomas will say later, ‘Deus voluit ab aeterno mundus esset sed non
ut ab aeterno esset’. God willed, for instance, that Socrates should be
born before Plato and He willed this from eternity, so that when it was time
for Plato to be born it happened. It is not difficult for Averroës to refute this
argument. In willing and doing something there is more than just the
decision that you will do it. You can take the decision to get up tomorrow,
but the actual willing to get up can be done only at the moment you do it,
and there can be no delay between the cause and the effect. There must
be added to the decision to get up the impulse of the will to get up. So in
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