 Traditionally, to hold a realist position with respect to X is to hold that X exists objectively. On this view, moral anti-realism is the denial of the thesis that moral properties—or facts, objects, relations, events, etc. (whatever categories one is willing to countenance)—exist objectively. This could involve either (1) the denial that moral properties exist at all, or (2) the acceptance that they do exist but this existence is (in the relevant sense) non-objective. There are broadly two ways of endorsing (1): moral noncognitivism and moral error theory. Proponents of (2) may be variously thought of as moral non-objectivists, or idealists, or constructivists. So understood, moral anti-realism is the disjunction of three theses: