If continuous quantity be quantity as far as it is continuous, then
definite quantity will no longer be quantity. If, on the contrary,
continuous quantity be quantity only accidentally, then there is
nothing in common between continuous and definite quantity. We will
grant that numbers are quantities, although if their nature of being
quantities were plain, one would not see why they should be given that
name. As to the line, the surface, and the body, they are called sizes
and not quantities; and the latter name is given them only when they
are estimated numerically; as when, for instance, they are measured
by two or three feet.[249] A body is a quantity only in so far as
it is measured, just as space is a quantity only by accident, and
not by its spatiality. We must here not consider what is quantity by
accident, but by its quantitativeness, quantity itself. Three oxen
are not a quantity; in this case, the quantity is the number found in
them. Indeed, three oxen belong already to two categories. The case
is similar with the line, and the surface, both of which possess such
quantity. But if the quantity of surface be quantity itself, why would
surface itself be a quantity? It is no doubt only when determined by
three or four lines that the surface is called a quantity.