Fact, science, and moralityde Graham Macdonald, Crispin WrightMateriasTheory of KnowledgePhilosophyExperienceLanguage and languagesPhilosophy, modern, 20th centuryAyer, a. j. (alfred jules) , 1910-1989Knowledge, theory ofLanguage and languages--philosophyB1618.a93 l3634 1987