What justifies private law as we find it? The book develops an answer through an inquiry into the core institutions of private law: tort, property, and contract. Avoiding the hermeneutical dead end of value pluralism predominant in current jurisprudence, the book insists on the question: what normative ideas deliver the most coherent foundation for the principles of private law? According to economic analysis, the increase of welfare is the ultimate end on which private law actually rests. But this conception does not even make contact with private law as it stands. In contrast, the ideas of equal freedom and corrective justice, long thought to be outdated, are still able to deliver a valid foundation. However, private law, insofar as this is its foundation, suffers from a fundamental deficit, which is reflected in the limitation of private law by public law. The book pursues an approach of "normative legal theory" which connects philosophy of law to legal doctrine and vice versa.