To write this excellent biography of John Muir, Donald Worster zealously ransacked the letters and journals of the great, self-taught naturalist. First the defender of Yosemite and the Sierra Nevada against exploitation, this president of the Sierra Club virtually founded the conservation movement, everywhere. Worster shows us both the private and public Muir. A “loner” on his mountain hikes, Muir was no hermit but a friendly, loquacious, good fellow. Muir’s rivals were few, but powerful enough to defeat him in his last battle, his fight to save the Hetch Hetchy Valley, Yosemite Valley’s twin, from becoming a dam site. Although he avoided politics like the plague, Muir was a true liberal. He opposed slavery and war; supported the vote for women; and defended Darwinian evolution. This well-written biography reveals a man whose mission in life was simply to entice people to see Nature’s loveliness.