 Western philosophical study of the aesthetics of the natural world reached a low point in the middle of the twentieth century, with the focus of analytic aesthetics almost exclusively on philosophy of art. At the same time, both the view that aesthetic appreciation of nature is parasitic upon that of art and even the idea that it is not in fact aesthetic appreciation at all were defended by some thinkers. However, in the last third of the century, there was a reaction to the neglect of the natural world by the discipline of aesthetics, which initiated a revival of the aesthetic investigation of nature and led to the emergence of environmental aesthetics.