On Sense And The Sensible   

remain separate, the analogy of the eyes will fail, [for of these some

one is really formed].

Furthermore, [on the supposition of the need of different parts of

Soul, co-operating in each sense, to discern different objects

coinstantaneously], the senses will be each at the same time one and

many, as if we should say that they were each a set of diverse

sciences; for neither will an 'activity' exist without its proper

faculty, nor without activity will there be sensation.

But if the Soul does not, in the way suggested [i.e. with

different parts of itself acting simultaneously], perceive in one

and the same individual time sensibles of the same sense, a fortiori

it is not thus that it perceives sensibles of different senses. For it

is, as already stated, more conceivable that it should perceive a

plurality of the former together in this way than a plurality of

heterogeneous objects.

If then, as is the fact, the Soul with one part perceives Sweet,

with another, White, either that which results from these is some

one part, or else there is no such one resultant. But there must be

such an one, inasmuch as the general faculty of sense-perception is

one. What one object, then, does that one faculty [when perceiving

an object, e.g. as both White and Sweet] perceive? [None]; for

assuredly no one object arises by composition of these

[heterogeneous objects, such as White and Sweet]. We must conclude,

therefore, that there is, as has been stated before, some one

faculty in the soul with which the latter perceives all its

percepts, though it perceives each different genus of sensibles

through a different organ.

May we not, then, conceive this faculty which perceives White and

Sweet to be one qua indivisible [sc. qua combining its different

simultaneous objects] in its actualization, but different, when it has

become divisible [sc. qua distinguishing its different simultaneous

objects] in its actualization?