The Nordic Summer University is committed to new developments in academic thought and practice. In this inaugural volume, NSU is proud to present the 2006 keynote lectures in print. The book offers a condensed tour de force through the major ethical theories of the twentieth century. In three historical chapters, beginning with Sidgwick and Nietzsche and ending with a response to the emergence of applied ethics, Sergio Cremaschi gives a unique overview of contemporary concerns about normative thinking under plural reasons.