||Conceptual analysis is one of the main traditional methods of philosophy, arguably dating back to Plato's early dialogues. The basic idea is that questions like 'What is knowledge?', 'What is justice?', or 'What is truth?' can be answered solely on the basis of one's grasp of the relevant concepts. The ideal result of a conceptual analysis would be a definition or analysis of the relevant X that is typically formulated as a necessary biconditional that states necessary and sufficient conditions for being X. For example, a typical formulation of the classical analysis of knowledge as justified true belief is: S knows that p iff (1) p is true, (2) S believes that p, and (3) S is justified in believing that p. Here, conditions (1) to (3) state individually necessary and jointly sufficient conditions for knowing that p. The standard procedure for testing such an analysis is by means of counterexamples, typically in the form of hypothetical cases as they are used in thought experiments. A counterexample may speak against the necessity of some of the conditions, or against the sufficiency of the conditions. For example, the classical analysis of knowledge was refuted by Gettier's (1963) famous counterexamples against the sufficiency of conditions (1) to (3). In such a situation, the analysis has to be refined until it is no longer subject to counterexamples, in which case it would constitute a successful conceptual analysis. Almost all of the elements of this traditional conception of conceptual analysis are controversial, but it still continues to guide a considerable amount of philosophical research.