1. The Setting of the Argument.- 1.1 Two Characteristics of Economic Analysis.- 1.2 The Provisional Nature of Economic Data.- 1.3 Intricacies in Macroeconomic Analysis.- 1.4 Isolation and Aggregation.- 2. On Isolation.- 2.1 The Heuristic View.- 2.2 The Isolating Approach.- 2.3 Substantive Isolation.- 2.4 Hypothetical Isolation.- 2.5 Economic Thinking.- 3. The Moving Equilibrium Method.- 3.1 Economic Equilibrium.- 3.2 Moving Equilibria.- 3.5 Hicks-d'Alembert's Principle.- 4. Econometric Implications.- 4.1 Linking Theory and Empirical Evidence.- 4.2 Invariances in Coefficients Versus Invariances in Their Stability.- 4.3 Estimation in a Linear Model with Random Walk Coefficients.- 4.4 Unsettled Problems.- 5. The Nature of Macroeconomic Laws.- 5.1 On Reductionism.- 5.2 The Macroeconomic Method.- 5.3 Closed Aggregation and the Context Dependency of Economic Laws.- 5.4 Qualitative Differences Between Microeconomic and Macroeconomic Laws.- 5.5 Hermeneutic Aggregation.- 5.6 Adequate Aggregation.- 6. Epilogue: Economic Imagination.- References.- Author Index.