where I lived and what I lived for

I think that living as a part of nature is the main idea here. Living in a society in which man ­ in the form of railroads, factories, and other technical innovations ­ had begun to tame and control nature, Thoreau counters the separation of man from society by conceiving of man as a part of nature. Through his life in the woods, living for the most part off the fruits of the land and deriving intellectual stimulation from plants and animals, Thoreau demonstrates that man can live successfully in the midst of nature.