Rodin's The Thinker is perhaps his best-known monumental work. First conceived about 1880 as the poet Dante, it was designed to occupy the center of the tympanum of The Gates of Hell, an unrealized scheme for a portal. In subsequent years, the figure evolved into a broader physical representation of the creative process. The Thinker was first exhibited in Paris at the Exposition Monet-Rodin in 1889 and an enlarged version was shown at the Paris Salon of 1904. Displayed at the 1915 Panama-Pacific International Exposition in San Francisco, this cast was purchased from the artist by Adolph and Alma Spreckels. It was one of the first of more than ninety Rodin sculptures that Mrs. Spreckels later donated to the Legion of Honor.