An idealist philosophical tendency among writers in and around Boston in the mid-19th century. Growing out of Christian Unitarianism in the 1830s under the influence of German and British Romanticism, Transcendentalism affirmed Kant's principle of intuitive knowledge not derived from the senses, while rejecting organized religion for an extremely individualistic celebration of the divinity in each human being. The leading Transcendentalist Ralph Waldo Emerson issued what was virtually the movement's manifesto in his essay Nature (1836), which presents natural phenomena as symbols of higher spiritual truths. The nonconformist individualism of the Transcendentalists is expressed in Emerson's essay ‘Self-Reliance’ (1841) and in Henry David Thoreau's Walden (1854)—a kind of autobiographical sermon against modern materialism. Others involved in the Transcendental Club in the late 1830s and with its magazine The Dial (1840–44) included Amos Bronson Alcott, Margaret Fuller, and William Ellery Channing. The Transcendentalists' manner of interpreting nature in symbolic terms had a profound influence on American literature of this period, notably in the works of Nathaniel Hawthorne, Herman Melville, and Walt Whitman. See also american renaissance. For an introductory anthology, consult George Hochfield (ed.), Selected Writings of the American Transcendentalists (2nd edn, 2004).