A brilliant essayist and a master of the aphorism ("Our moods do not believe in each other"; "Money often costs too much"), Emerson has inspired countless writers. He challenged Americans to shut their ears against Europe's "courtly muses" and to forge a new, distinctly American cultural identity. But he remains one of America's least understood writers. And, by his own admission, he spawned neither school nor follower (he valued independent thought...