 Although Sidgwick published extensively in his lifetime, he is best known for his first major book, The Methods of Ethics, which first appeared in 1874 and went through five editions during his lifetime. His second most widely read book would be his Outlines of the History of Ethics for English Readers, which appeared in 1886 as an expanded version of the article on the subject that he had contributed to the famous ninth edition of the Encyclopedia Britannica. But he also published The Principles of Political Economy (1883), The Elements of Politics (1891), and Practical Ethics, A Collection of Addresses and Essays (1898), and after his death, Eleanor Sidgwick worked with various of his former colleagues to bring out Lectures on the Ethics of T. H. Green, H. Spencer, and J. Martineau (1902), Philosophy, Its Scope and Relations (1902), The Development of European Polity (1903), Miscellaneous Essays and Addresses (1904), Lectures on the Philosophy of Kant and Other Philosophical Lectures and Essays (1905), and Henry Sidgwick, A Memoir (1906), which Eleanor and Arthur Sidgwick assembled largely from his correspondence and journal. These posthumous works are typically quite polished and shed a great deal of light on the works that Sidgwick himself saw through publication (Schneewind 1977).