"Robert Green 'Bob' Ingersoll (August 11, 1833-July 21, 1899) was an American lawyer, a Civil War veteran, political leader, and orator ... during the Golden Age of Free Thought, noted for his broad range of culture and his defense of agnosticism. He was [among other epithets like Colonel Bob] nicknamed 'The Great Agnostic'"--Wikipedia ("Robert G. Ingersoll" viewed February 4, 2016)
