  The non-naturalists, however, had neglected another option consistent with the thought underlying the open question argument. Perhaps moral predicates did not refer to properties at all, and perhaps their meaning was not analyzable in non-moral descriptive terms not because they referred to irreducibly moral properties but because, despite appearances, they were not referring expressions at all. In other words, semantic nonfactualism about moral terms entails that questions of the sort highlighted by Moore could not be closed by any amount of competence with the expressions used to ask them because the expressions in question are not in fact equivalent. Thus non-cognitivists could argue that moral expressions used in such open questions did not function to represent anything or to predicate any property and as such were not equivalent to any descriptive or referring expressions. Rather they merely served to convey emotion (Ogden and Richards 1923, 125). Speakers to whom such questions seemed open were tacitly aware of this difference in function and hence not in a position to equate moral expressions with descriptive expressions.