22 works by or responding to Ludwig Wittgenstein (1889–1951), considered by many to be the greatest philosopher of the 20th century. Highlights include Wittgenstein’s own annotated copy of Moritz Schlick’s 1930 book on ethics, and a collection of working copies of Wittgenstein from one of his major interpreters, Sir Anthony Kenny. Wittgenstein’s cultural influence is also explored in art, literature, and film, by Eduardo Paolozzi, Veronica Forrest-Thomson, and Derek Jarman.