`Quite delightful. Lehrer is certainly a master stylist. In addition to its stylistic virtues, this book contains clear and careful accounts (and critiques) of traditional, modern and contemporary theories. His own views are developed in new and interesting ways that will command attention.' - Jonathan Kvanvig, Texas A & M University`Attains something both difficult and rare, as it introduces the student brilliantly to the field and also guides him to the cutting edge.' - Ernest Sosa, Brown University