  Where does an investigation into a topic such as sophistry or statesmanship begin? At the start of the search for the sophist, the Eleatic visitor remarks that he and Theaetetus may share merely the name “sophist” in common but may mean quite different things by the name. He aims to establish agreement about the kind to which they ascribe the name (Sophist 218b–c), and he wants to find a real definition—a definition that applies to all and only members of the kind, and one that explains why any instance is an instance of that kind: the inquirers seek the essence of the target kind, the property or collection of properties that make the kind what it is.