Oh my god, the "moral anti-realism" article has what is possibly the best opening paragraph I've seen in the SEP:

It might be expected that it would suffice for the entry for “moral anti-realism” to contain only some links to other entries in this encyclopedia. It could contain a link to “moral realism” and stipulate the negation of the view there described. Alternatively, it could have links to the entries “anti-realism” and “morality” and could stipulate the conjunction of the materials contained therein. The fact that neither of these approaches would be adequate—and, more strikingly, that following the two procedures would yield substantively non-equivalent results—reveals the contentious and unsettled nature of the topic.