Volume XII,  Natural History of the Intellect, was published by Emerson's editor and first biographer, James Elliot Cabot. The lectures in this volume were begun in England, worked on over the years, repeated during a Harvard course in 1871 and finally published in 1893, after Emerson's death. The essays are particularly important for a complete understanding of Emerson's view of the mind and his ongoing interest in the nature of consciousness.