“…"by concentrating attention on some, but not all, of what is presented" (Campbell 1981, 477-478). 2 The advocates of standard trope nominalism include Williams (1953aWilliams ( , 1953b, Campbell (1981Campbell ( , 1990, Maurin (2002), Simons (2003), and Giberman (2014). By contrast, Ehring (2011) claims that the nature of a trope must be determined extrinsically, by its belonging to a primitive natural class.…”