derivation of purposive natural products is consistent with the teleological, but in no way enables us to dispense with it. In a thing that we must judge as a natural purpose (an organised being) we can no doubt try all the known and yet to be discovered laws of mechanical production, and even hope to make good progress therewith; but we can never get rid of the call for a quite different ground of production for the possibility of such a product, viz.

causality by means of purposes. Absolutely no human Reason (in fact no finite Reason like ours in quality, however much it may surpass it in degree) can hope to understand the production of even a blade of grass by mere mechanical causes. As regards the possibility of such an object, the teleological connexion of causes and effects is quite indispensable for