surface be very necessary for the origin and maintenance of the vegetable and animal kingdoms, it has nothing in itself for the possibility of which we are forced to assume a causality according to purposes. The same is true of plants which man uses for his needs or his pleasures; of beasts, the camel, the ox, the horse, dog, etc., which are indispensable to him as well for food as because they are used in his service in many different ways.

In the case of things which we have no reason for regarding in themselves as purposes, such external relation can only be hypothetically judged as purposive.

To judge of a thing as a natural purpose on account of its internal form is something very different from taking the existence of that thing to be a purpose of nature. For the latter assertion