行政学
More recently scholars claim that "public administration has no generally accepted definition", because the "scope of the subject is so great and so debatable that it is easier to explain than define". Public administration is a field of study (i.e., a discipline) and an occupation. There is much disagreement about whether the study of public administration can properly be called a discipline, largely because of the debate over whether public administration is a sub-field of political science or a sub-field of administrative science", the latter an outgrowth of its roots in policy analysis and evaluation research. Scholar Donald Kettl is among those who view public administration "as a sub-field within political science". According to Lalor a society with a public authority that provides at least one public good can be said to have a public administration whereas the absence of either (or "a fortiori" both) a public authority or the provision of at least one public good implies the absence of a public administration. He argues that public administration is the public provision of public goods in which the demand function is satisfied more or less effectively by politics, whose primary tool is rhetoric, providing for public goods, and the supply function is satisfied more or less efficiently by public management, whose primary tools are speech acts, producing public goods. The moral purpose of public administration, implicit in its acceptance of its role, is the maximization of the opportunities of the public to satisfy its wants.