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

consider the mistake in it we have already mentioned. And for exactly the
same reason the proof of the Ash’arites that every temporal occurrence
needs a cause does not lead to an eternal First Principle which is not
composite, but only to a First Principle which is not temporal.
As to the fact that knower and knowledge are one, it is not impossible,
but necessary, that such pairs of things lead up to the unity of their
concepts; e. g. if the knower knows through knowledge, that through
which he becomes a knower is more apt to be a knower, for the quality
which any thing acquires from another is in itself more apt to possess the
concept which is acquired, e. g. if the living bodies in our sublunary world
are not alive by themselves, but through a life which inheres in them, then
necessarily this life through which the non-living acquires life is alive by
itself, or there would be an infinite regress; and the same is the case with
knowledge and the other attributes.
Now, it cannot be denied that one essence can have many attributes
related, negative, or imaginary, in different ways without this implying a
plurality in the essence, e. g. that a thing is an existent and one and
possible or necessary, l for when the one identical entity is viewed in so
far as something else proceeds from it, it is called capable and acting, and
in so far as it is viewed as differentiating between two opposite acts, it is
called willing, and in so far as it is viewed as perceiving its object,
knowing, and in so far as it is viewed as perceiving and as a cause of
motion, it is called living, since the living is the perceiving and the selfmoving.
What is impossible is only a single simple existence with a
plurality of attributes, existing by themselves, and especially if these
attributes should be essential and exist in act, and as to these attributes
existing in potency, it is not impossible, according to the philosophers, that
something should be one in act and a plurality in potency, and this is the
case according to them, with the parts of the definition in their relation to
the thing defined.
And as to Ghazali’s words:
And they affirm that this causes a plurality . . . that they
are two.
He means by them that the fact that these attributes are simultaneous
with the essence does not prevent them from being necessarily a plurality
256