 A further challenge for attempts to experimentally investigate moral semantics is the debate within antirealism between cognitivism and noncognitivism. According to the cognitivist, ordinary moral sentences are best understood as factual assertions, expressing propositions that attribute moral properties (such as rightness or goodness) to things (such as actions or characters). Noncognitivists (including their contemporary representatives, the expressivists) hold that moral language has a fundamentally different function, to express attitudes or to issue commands, for example. While this debate seems ripe for experimental investigation, the noncognitivist typically acknowledges that their view is a reforming one. Furthermore, the semantics of our terms may be opaque to ordinary users, to the extent that we cannot read off semantics from intuitions but must investigate them indirectly. Lastly, the cognitivist and noncognitivist can agree on a number of empirical features of moral judgment and discourse; the challenge for experimentalists is to find predictions that confirm one view while disconfirming the other. This is a relatively new area of investigation and, while not without challenges, ripe for exploration.