Upton Sinclair? W. E. B. Du Bois? George Orwell? George Bernard Shaw? Ann Petry? Morris Edmund Speare? Richard Hunt? Ludwig Lewisohn? Edmund Wilson? Anonymous? Question for Quote Investigator: Advocates often extoll their visions with strong-willed certainty. Insistent artists are accused of preaching and propagandizing. Yet, this criticism is sometimes provocatively embraced. Here are three assertions: …