 However, while the philosophical study of the aesthetics of nature languished in Europe, a new way of understanding the aesthetic appreciation of the natural world was developing in North America. This conception of nature appreciation had roots in the American tradition of nature writing, as exemplified in the essays of Henry David Thoreau. It was also inspired by the idea of the picturesque and, to a lesser extent, that of the sublime, especially in its artistic manifestations, such as the paintings of Thomas Cole and Frederic Church. However, as nature writing became its more dominant form of expression, the conception was increasingly shaped by developments in the natural sciences. In the middle of the nineteenth century, it was influenced by the geographical work of George Perkins Marsh (Marsh 1865), who argued that humanity was increasingly causing the destruction of the beauty of nature. The idea was forcefully presented toward the end of the century in the work of American naturalist John Muir, who was steeped in natural history. Muir explicitly distinguished this kind of understanding of the aesthetic appreciation of nature from that governed by the idea of the picturesque. In a well-known essay, “A Near View of the High Sierra” (Muir 1894), two of Muir’s artist companions, who focus on mountain scenery, exemplify aesthetic experience of nature as guided by the idea of the picturesque. This differs from Muir’s own aesthetic experience, which involved an interest in and appreciation of the mountain environment somewhat more akin to that of a geologist. This way of experiencing nature eventually brought Muir to see the whole of the natural environment and especially wild nature as aesthetically beautiful and to find ugliness primarily where nature was subject to human intrusion. The range of things that he regarded as aesthetically appreciable seemed to encompass the entire natural world, from creatures considered hideous in his day, such as snakes and alligators, to natural disasters thought to ruin the environment, such as floods and earthquakes. The kind of nature appreciation practiced by Muir has become associated with the contemporary point of view called “positive aesthetics” (Carlson 1984). Insofar as such appreciation eschews humanity’s marks on the natural environment, it is somewhat the converse of aesthetic appreciation influenced by the idea of the picturesque, which finds interest and delight in evidence of human presence.