Why should these numbers be considered quantities? Doubtless because
they are measures. But are these measures quantities, or quantity
itself? As they are in the order of beings, even if they should not
apply to any of the other things, the numbers will nevertheless remain
what they are, and they will be found in quantity. Indeed, their unity
designates an object, since it applies to another; then the number
expresses how many objects there are, and the soul makes use of number
to measure plurality. Now, when measuring thus, the soul does not
measure the "whatness" (or, quality) of the object, since she says
"one," "two," whatever be their objects, even if of opposite nature;
she does not determine the character of each thing, for instance, if it
be warm or beautiful; she limits herself to estimating its quantity.
Consequently, whether we take Number in itself, or in the objects which
participate therein, quantity exists not in these objects, but in the
number; quantity finds itself not in the object three feet long, but in
the number three.