This paper questions popular perceptions of the "ordinary reasonable person", defamation law's measure as to what is defamatory. Developing Robert Post's understanding of defamation law as policing society's "rules of civility" in relation to communications, this paper discusses how different understandings of ordinariness and reasonableness contribute to the law's mapping of the moral community. In particular the paper raises two issues. The first relates to the way in which the law deals with discord within the community of "ordinary reasonable persons". The paper demonstrates the uncertainty as to whether minority viewpoints are relevant in defamation law, a confusion originating in conflicting legal precedents. The second issue explored is the impact on defamation law of the phenomenon known as the "third person effect" and the potential for this to unnecessarily restrict speech. The relevance of both issues to law reform is then explored. The paper presents research-in-progress of the National Defamation Research Project, an unprecedented examination of Australian social attitudes run by the Communications Law Centre at the University of New South Wales.