7. But what is the conception of unity under which beings are presented to us? There is unity in the object when there is no distinction in the conception presenting it; and there is no distinction, when the perception of relative _not-being_ is not combined in the object with that of _being_. We have unity whenever we perceive an object simply. Suppose that we perceive the object B. No matter what B is, it will to us be always one, unless we perceive it as composed of C, D, one of which is not the other. If we perceive in the object B, a distinction between C and D, unity disappears. Evidently when we are aware of this composition we can abstract it and simply consider the result, the whole, B; and then unity appears anew. 8. We see by this that unity may be either real or fictitious. It is real and existing when there is no distinction in the thing either real or apparent; it is fictitious in those composites which of themselves include distinct things that may be offered to the understanding, inasmuch as they are subordinated to one unity of order, abstraction made of the real distinction contained in them. 9. The schoolmen sometimes defined what is _one_ to be, "ens indivisum in se, et divisum ab aliis." The former part seems sufficiently exact if by _indivisum_ is meant _non-distinctum_ and not _non-separatum_; but the second part must be regarded at the best as superfluous. If there existed only one most simple and sole being, it would yet be one, although we could not say that it was divided from others, _divisum ab aliis_; for as there would be _no others_ it could not be divided from them. This part of the definition is therefore superfluous. 10. It is no solution of the difficulty to say that this one being is divided from others, real or possible, and that in the supposition of one only being, others are possible although not real. The only being would be _really one_, and the division from others would be only _possible_; since there can be no real distinction between two terms when one of them is only possible. The division from others, _divisis ab aliis_, therefore is not a necessary element of unity, because unity is real, and this element is only possible. 11. However, in confirmation of this doctrine, we may remark, that in common parlance, unity is opposed to distinction, and there is no unity where there is no distinction. If the only being be not conceived as multiple there can be no distinction; and this is so independently of its being compared with the rest. The words, _others_, and _the rest_, suppose single beings; the idea of unity precedes that of distinction; beings are not considered as distinct between themselves until after they are conceived as individually single.