Cover; Half Title; Title Page; Copyright Page; Table of Contents; List of Figures; Preface; 1: New Directions in the Theory of Explanation; 2: Explanation and Mechanism; 3: The Instance Theory of Explanation; 4: Errors of Measurement and Explanation-as-Unification; 5: Theoretical Explanation and Errors of Measurement; 6: Ellis' Theory of Quantities; 7: Bigelow and Pargetter on Quantities; 8: Laws of Nature; 9: Laws as Relations between Quantities; 10: Quantum Mechanical Quantities; 11: Explanation and the Quantum State; 12: Reflections and Conclusions; Bibliography; Index