according to purposes seems to make the Idea of a natural purpose into a constitutive principle, which Idea has thus something different from all other Ideas.

This difference consists, however, in the fact that the Idea in question is not a rational principle for the Understanding but for the Judgement. It is, therefore, merely the application of an Understanding in general to possible objects of experience, in cases where the judgement can only be reflective, not determinant, and where, consequently, the object, although given in experience, cannot be determinately judged in conformity with the Idea (not to say with complete adequacy), but can only be reflected on.

There emerges, therefore, a peculiarity of our (human) Understanding in respect of the