“In wildness is the preservation of the world,” wrote Henry David Thoreau in 1851 at a time when he was one of the few thinking about environmental conservation. Six years previous he had embarked on a now-famous experiment in simple living. He’d gone to the woods outside Boston to live in a 150-square-foot cabin to avoid living “what was not life”.

“I went to the woods because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not, when I came to die, discover that I had not lived.”

He spent two years, two months and two days in his cabin at Walden Pond and in 1854, he published his reflections on life in the woods in the book Walden. The book is credited with helping to inspire environmental awareness, but his messages were often simple: “Our life is frittered away by detail… Simplicity, simplicity, simplicity!”

Today, his life, and work, are an inspiration for followers of downshifting and simplicity movements, but due to his detailed observations of the natural world during his days at Walden, his work is now being used to help modern scientists study climate change.

When he died in 1862, the industrial revolution was just beginning to pump greenhouse gases into the atmosphere. His recordings of when and where plants flowered in the area is now being studied to show patterns of climate change.

Conservation biologists reported in 2008 – based on Thoreau’s research- that common species are flowering 7 days earlier than they did during his day and 27% of the species he studied have disappeared (another 36% are endangered).

In this video, Michael Mitchell of the Walden Pond State Reservation gives us a tour of the site of Thoreau’s original cabin and talks about his life in the woods.