First, To explain the PRINCIPIUM INDIVIDUATIONIS, or principle of identity.
Secondly, Give a reason, why the resemblance of our broken and interrupted perceptions induces us to attribute an identity to them.
Thirdly, Account for that propensity, which this illusion gives, to unite these broken appearances by a continued existence.

Fourthly and lastly, Explain that force and vivacity of conception, which arises from the propensity.
First, As to the principle of individuation; we may observe, that the view of any one object is not sufficient to convey the idea of identity.
For in that proposition, an object is the same with itself, if the idea expressed by the word, object, were no ways distinguished from that meant by itself; we really should mean nothing, nor would the proposition contain a predicate and a subject, which however are implyed in this affirmation.

One single object conveys the idea of unity, not that of identity.
On the other hand, a multiplicity of objects can never convey this idea, however resembling they may be supposed.

The mind always pronounces the one not to be the other, and considers them as forming two, three, or any determinate number of objects, whose existences are entirely distinct and independent.
Since then both number and unity are incompatible with the relation of identity, it must lie in something that is neither of them.

But to tell the truth, at first sight this seems utterly impossible.