The Thinker (Le Penseur) by Auguste Rodin https://www.nga.gov/artworks/1005-thinker-le-penseur
The Thinker was originally conceived not in heroic isolation, but as part of Rodin’s monumental Gates of Hell —a pair of bronze doors intended for a museum of decorative arts in Paris. Although the doors were never cast during the sculptor’s lifetime, they nevertheless provided Rodin a rich source of ideas for individual figures and groups that he worked and reworked for the rest of his career.
Vienna, 1953: 27-28. 1963 Elsen, Albert E. Rodin. New York, 1963: 52-54.