On the Improvement of the Understanding

VII. By particular things, I mean things which are finite and have a conditioned existence; but if several individual things concur in one action, so as to be all simultaneously the effect of one cause, I consider them all, so far, as one particular thing.

VI.Reality and perfection I use as synonymous terms.

V.Duration is the indefinite continuance of existing.

Explanation.—I say indefinite, becouse it cannot be determined through the existence itself of the existing thing, or by its efficient cause, which necessarily gives the existence of the thing, but does not take it away.