Realism issues tend to be confusing because of the bewildering number of “defi nitions” of what realism is. A large part of the problem, I have argued in Realism and Truth (1997), is that doctrines that should be metaphysical have become entangled with epistemological and semantic doctrines. The various realism issues in biology do not seem to have that problem, but there is still some unclarity about the nature of those issues, as David Hull notes. The most active of the issues arises out of the debate between “species monists” who think that there is just one good “species concept”—one good account of what it is to be a species-and “species pluralists” who think that there are many. Hull fi nds the combinations of monism + realism and pluralism + antirealism “quite natural” but the combinations of monism + antirealism and pluralism + realism “somewhat strained.” Still, he notes that “real can be defi ned in such a way” as to remove these strains (1999, 25-26). So he sees the issue as partly a verbal one over defi nitions.1