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

exist both an essence and attributes additional to the essence, consists in
this: that the essence becomes a condition for the existence of the
attributes and the attributes a condition for the perfection of the essence,
and that their combination would be a necessary existent, that is, one
single existent in which there is neither cause nor effect. And this latter
difficulty cannot be really solved when it is assumed that there exists an
essentially necessary existent, for this implies that it must be one in every
way and can in no way be composed of the condition and the conditioned
and of cause and effect, for such a composition would have to be either
necessary or possible; (t) if necessary, it would be necessary through
another, not through itself, since it is difficult to assume an eternal
compound as existing through itself, i. e. as not having a cause for its
composition, and this is especially difficult for the man who believes that
every accident is temporal, ‘ since the fact of being a compound would be
an eternal accident; (2) if possible, a cause would be needed to join
together the effect and the cause. Now, according to philosophical
principles it is quite impossible that there should be a compound existing
by itself, having eternal attributes, since the composition would be a
condition of its existence; and its parts could not be agents for the
composition, for the composition would have to be a condition for their
existence. Therefore, when the parts of any natural compound are
disjoined, their original name can be only applied to them equivocally, e. g.
the term `hand’, used of the hand which is a part of the living man and the
hand which has been cut off; and every compound is for Aristotle
transitory and a fortiori cannot be without a cause?
But as to the system of Avicenna, with its division of the necessary
existent from the possible existent, it does not lead to the denial of an
eternal compound; for when we assume that the possible ends in a
necessary cause and that the necessary cause must either have a cause
or not, and in the former case must end in a necessary existent which has
no cause, this reasoning leads through the impossibility of an infinite
regress to a necessary existence which has no efficient causenot,
however, to an existent which has no cause at all, for this existent might
have a formal or a material cause, unless it is assumed that everything
which has matter and form, or in short every compound, must have an
external cause; but this needs a proof which the demonstration based on
the principle of the necessary existent does not contain, even if we do not
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