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

I say:
of reason. ‘ And to ask whether humanity can be free from
animality is like asking whether humanity can be without
itself, when something is added to it. And indeed genus and
species are more distant from plurality than attribute and
subject. ‘ And why should it be impossible that the causal
series should end in two causes, one the cause of the
heavens and the other the cause of the elements, or one the
cause of the intellects and the other the cause of all bodies,
and that there should be between those two causes a
conceptual difference and separation as between redness
and warmth when they exist in one and the same place? For
they differ in content without our being obliged to assume in
the redness a compound of genus and specific difference
through which this difference is established; indeed, if it
possesses a plurality, this kind of plurality does not impair
the singleness of its essence, and why should this be
impossible with respect to the causes? Through this there is
shown the weakness of their refutation of the existence of
two Gods.
Composition out of genus and specific difference is exactly the same as
the composition of a thing in potency and a thing in act, for the nature
which is indicated by the genus does not actually exist at any time without
the presence of the nature which is called specific difference and form. ;
And everything which is composed of these two natures is, according to
the philosophers, transitory, and possesses an agent, for the specific
difference is one of the conditions for the existence of the genus in so far
as the genus is in potency and does not exist without the specific
difference. And the conjunction of either with its partner is in a certain way
a condition for the existence of the other. And as a thing cannot itself be a
cause of the condition of its existence, it necessarily possesses a cause
which provides it with existence by conjoining the condition and the
conditioned. Also, according to the philosophers the recipient is in reality
something which possesses only potency, and if it is actually, then only
accidentally; and what is received is actuality, and if it is potency, then
only accidentally; for the recipient and the thing it receives are only
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