“…to focus on purely philosophical matters such as compositional nihilism (there are no composite objects; Rosen and Dorr 2002 , Sider ms.), artifact nihilism (there are no artifacts; van Inwagen 1990, Merricks 2001, moral error theory (there are no positive, fi rst-order, substantive moral truths; Mackie 1977 ), mathematical error theory (there are no positive, fi rst-order, substantive mathematical truths; Field 1980, Field 1989, Balaguer 1998, semantic nihilism (no assertions made with or beliefs expressed with vague terms are true; Sider and Braun 2007 ), and radical skepticism (there is virtually no knowledge). 3 The line between the philosophical theses with little or no scientifi c backing and those with signifi cant scientifi c backing is usually considered to be generously fuzzy, but there are obvious examples on either side of the line.…”