By the age of thirty Emerson had become a well-respected Unitarian minister in Boston. Broken hearted after the death of his young wife and disillusioned with the cold beliefs of the Unitarianism of his day, he resigned the ministry, sold most of his belongings and sailed for Europe in 1832. He achieved a spiritual rebirth of sort from two discoveries made in his European visit. When visiting the Museum of Natural History in Paris and contemplating the variety and majesty of biological life he saw there, he began looking to nature for truth, rather than the doctrines of revealed religion. When he visited Thomas Carlyle in Scotland, who introduced him to the work of the German transcendentalists, he found a new grounding for his spirituality in Neoplatonism and he began to rely on the inner process of intuition for the source of truth, rather than the rationalism of the Enlightenment. Free from the doctrines of Christianity and the dead rationalism of the Enlightenment, he returned to Boston and delivered three pieces which would complete America's independence from Europe and give birth to the American Renaissance.
The World as a grand, benevolent paradise
In 1836 he wrote a book of essays called Nature, which would provide the basis for the Transcendentalist view of the world as being a grand, benevolent paradise, free from the arbitrary dictates of God taught by the church but also free of the distant rationalism of Enlightenment thinkers. In Nature he was free to lose himself, become free of all egoistic character and to become a “giant eyeball” observing as nature flowed through him. Nature became the manifest for Thoreau and the small band of writers centered in Concord who would become known as the Transcendentalists.
Man as Free Thinker
In August 1837 Emerson delivered a speech entitled The American Scholar to the Phi Beta Kappa Society at Harvard in which he called for a higher use of the mind and thinking capacity. Freedom is achieved by the willingness to reject old concepts and to explore for oneself the veracity of all claims. This speech, which Oliver Wendell Holmes, Sr. declared to be America's “intellectual declaration of independence,” can be said to be New Thought's basis for pure individual discovery of truth, free from revealed religion and doctrinal theology.
The Divinity of Man
In July 1838 Emerson delivered the the commencement address to Harvard Divinity School, known as The Divinity School Address. The opening paragraphs of this speech were more than controversial. They were in fact incendiary, challenging the supernatural character of Jesus and his miracles, critiquing the dead, dry, rationalist preaching of the day and, most important, raising the status of human beings to divine status.
Emerson was essential to the development of New Thought. Marcus Bach says that Charles Fillmore read Emerson endlessly, attempting to understand why metaphysical religion worked (:18). Tom Shepherd once shared with me that one can't really understand Unity without understanding Emerson and Transcendentalism. All the wisdom of the antecedents of New Thought were channeled in some form through Emerson and, combined with the unique contributions of their new appreciation of Nature, they provide the philosophical basis for New Thought thinking.