summa-contra-gentiles

CHAPTER LXXXII 235
of its own, not only in moving but also in sensing.* For
he declared that sensation is
which senses :
a movement of the soul itself
and that the soul, being moved thus, moved
Wherefore when he defined sense
the body to sensation.^
he said that it is the movement of the soul through the body.^
Now it is clear that these statements are false. For to
sense is not to move, but to be moved: because from being
potentially sentient the animal is made actually sentient
through the sensible objects by
which the senses are
impressed. But it cannot be said that the sense is passive
to the sensible in the same way as the intellect is passive to
the intelligible object, so that sensation could be an operation
of the soul without a bodily instrument, in the same
way as understanding is. For the intellect apprehends
things as abstracted from matter and material conditions
whereas the sense
which are the principles of individuality ;
does not. This is evidenced bv the sense heinjy ronfined to
particular objects, while ^lnde^Sfanr^1n^Ms[of jmiyersals . 1 1
is therefore clear that the senses are passive to things as
existing in matter while the intellect : is not, but according
as they are subject to abstraction. Therefore the passion of
the intellect is without corporeal matter, whereas the passion
of the senses is not.
Again. Different senses are receptive of different
sensibles, sight, for instance, of colours, hearing of sounds.
Now this difference clearly arises from the different dispositions
of the organs for the organ of :
sight needs to be in
potentiality to all colours, and the organ of hearing to all
sounds. But if this reception took place without any
corporeal organ, the same faculty would be receptive of all
sensible objects
: since an immaterial power, for its own
part, stands in an equal relation to all such qualities :
wherefore the intellect, through not using a corporeal
organ, takes cognizance of all sensible objects. Therefore
there is no sensation without a corporeal organ.
Further. Sense is
corrupted by excellence of its object;
but the intellect is
not, because he who understands higher
1 Cf. Theatet. xn.
« Cf. Philcb. xix. ; Leges, x. 896.
• Cf. Timceus, 43.