istences, or from without, as when an artist forms a statue. In either case, there is an operative cause, through which the materials are moulded into form, Then, lastly, there is the end or final cause. Everything exists for some purpose. We may not know for what purpose, but we must think that everything exists for some purpose, and this purpose is called its end or final cause. A final cause always implies intelligence, which an efficient cause does not necessarily imply.
8. The three latter principles, essence, efficient cause, and end, are said by Aristotle to be very closely united, and often, indeed, to run into one. It is not difficult to see the identity of essence and end. Thus, for example, the possession of reason is the essence of man, and the possession of reason is also his end, or the most important part of his end. But it is not easy to identify efficient cause with the other two principles. I may here remark that Aristotle's conception of ends differs from that of Paley and other modern philosophers in being more comprehensive than theirs. Paley dwelt on the useful contrivances observable in the structure of organised bodies, and from thence inferred the existence of an intelligent designer. The same argument is implied in Aristotle. But he, moreover, holds that in everything that exists there is an indwelling end or purpose, and that this end or purpose is as much involved, although not so obtrusive or conspicuous, in such simple structures as
