Collingwood understands nature to be related integrally to mind. An explanation of the relationship between nature and mind is central to Collingwood's philosophy. Collingwood conceives of mind as emerging within and acting upon the phenomena of nature. Collingwood's writings that are devoted specifically to nature, notably The Idea of Nature and "Notes towards a Metaphysic", the latter of which remains as yet unpublished in its entirety, invoke nature's dependence on mind in distinct but related ways. The focus of this chapter is upon Collingwood's explorations of nature, as mind is serially examined in all chapters, because the mind informs all the reflective activities undertaken and examined by Collingwood. Mind is nonetheless discussed because the relationship of nature to mind is a salient feature of Collingwood's understanding of nature. For Collingwood, mind is implicated in the study of nature in two ways that harmonize with two styles of rethinking that are undertaken by Collingwood, and which are distinguished in the Introduction to this work. On the one hand, Collingwood considers that nature is only to be understood by historic acts of mind, so that the idea of nature thereby entails an historical engagement with the development of historical thinking about nature. On the other hand, nature itself is to be understood as exhibiting patterns of rationality that are related to mind by their approximation to the intelligible relations of thought that are maintained and comprehended in human thought and practice.