What distinctions are admitted by continuous quantity? There is the
line, the surface, and the solid; for extension may exist in one,
two or three dimensions (and thus count the numerical elements of
continuous size) instead of establishing species.[389] In numbers thus
considered as anterior or posterior to each other, there is nothing in
common, which would constitute a genus. Likewise in the first, second
and third increases (of a line, surface, and solid) there is nothing in
common; but as far as quantity is found, there is also equality (and
inequality), although there be no extension which is quantitative more
than any other.[390] However, one may have dimensions greater than
another. It is therefore only in so far as they are all numbers, that
numbers can have anything in common. Perhaps, indeed, it is not the
monad that begets the pair, nor the pair that begets the triad, but it
may be the same principle which begets all the numbers. If numbers be
not derivative, but exist by themselves, we may, at least within our
own thought, consider them as begotten (or, derivative). We conceive
of the smaller number as the anterior, the greater as posterior. But
numbers, as such, may all be reduced to unity.