Full Idea
For Kant the idea of nature is the idea of the realm of law, the idea that came into focus with the rise of modern science.
Gist of Idea
Kant identifies nature with the scientific picture of it as the realm of law
Source
report of Immanuel Kant (Critique of Pure Reason [1781]) by John McDowell - Mind and World V.4
Book Reference
McDowell,John: 'Mind and World' [Harvard 1996], p.96
A Reaction
Any doubts about the existence of laws of nature (e.g. Ideas 5470, 6781, 5474) would pull the mat out from under this view. I am inclined to view nature as the realm of natural kinds, which give rise to the regularities we call 'laws'.
Related Ideas
Idea 5470 The idea of laws of nature arose in the Middle Ages [Hall,AR, by Ellis]
Idea 6781 There are fundamental explanatory laws (false!), and phenomenological laws (regularities) [Cartwright,N, by Bird]
Idea 5474 Laws of nature tend to describe ideal things, or ideal circumstances [Ellis]