As outspoken in his day as Richard Dawkins or Christopher Hitchens are today, American freethinker and author ROBERT GREEN INGERSOLL (1833-1899) was a notorious radical whose uncompromising views on religion and slavery (they were bad, in his opinion), women's suffrage (a good idea, he believed), and other contentious matters of his era made him a wildly popular orator and critic of 19th-century American culture and public life. As a speaker dedicated...