Critique of Judgement by Immanuel Kant Chapter 82 Page 4

hardly separate from the concept of an organised thing; for, since we must place at the basis of its internal possibility a causality of final causes and an Idea lying at the ground of this, we cannot think the existence of this product except as a purpose. For the represented effect, the representation of which is at the same time the determining ground of the intelligent cause working towards its production, is called a purpose.

In this case therefore we can either say: The purpose of the existence of such a natural being is in itself; i.e. it is not merely a purpose but a final purpose, or: This is external to it in another natural being, i.e. it exists purposively not as a final purpose, but necessarily as a means.

But if we go through the whole of nature