Ralph Waldo Emerson has traditionally been cast as a dreamer and a mystic, concerned with the ideals of transcendentalism rather than the realities of contemporary science and technology. In Laura Dassow Walls's view Emerson was a leader of the secular avant-garde in his day. He helped to establish science as the popular norm of truth in America and to modernize American popular thought. In addition, he became a hero to a post-Darwinian generation of Vicorian Dissenters, exemplifying the strong connection between transcendentalism and later nineteenth-century science.
While visiting the Paris Museum of Natural History during his first European tour, Emerson experienced a revelation so intense that he declared, "I will be a naturalist". Once he was back in the United States, his first step in realising this ambition was to deliver a series of lectures on natural science. These lectures formed the basis for his first publication, Nature (1836), and his writings ever after reflected his intense and continuing interest in science.