This pair of papers involves a reprinting of "Of Harms and Benefits: Torts, Restitution, and Intellectual Property," 21 J. LEGAL STUDIES 449 (1992), along with an introduction to that article for students, entitled "Copyright as Tort's Mirror Image". Both involve comparisons between statutory intellectual property law and common law doctrines. "Copyright as Tort's Mirror" uses personal injury law to introduce students to copyright, making a link between the doctrines through the notion of "externalities". Just as tort law discourages wastefully harmful behavior by making perpetrators bear some of the costs inflicted, copyright law encourages beneficial behavior by enabling authors to capture some of the benefits generated. For persons trained in common law doctrines, therefore, it may be useful to approach copyright law initially as if copyright were tort law upside-down. While a full economic account of copyright needs to go far beyond the tort analogy (to consider factors such as industry structures, the "public goods" character of authorial work, and so on), the analogy to torts has many applications. Notably, it can help students understand some of the reasons why the law puts limitations on copyright. For example, consider the motto, "It takes two to tort", and its lesson that both plaintiffs and defendant may need incentives. In tort, the defense of comparative negligence serves to encourage potential victims to take care; in copyright, rules such as non-ownership of ideas encourage potential follow-on innovators to build on their predecessors. "Copyright as Tort's Mirror" also emphasizes the imperfection of the torts-copyright analogy. Among other things, I suggest, gratitude is often an easier emotion to achieve than forgiveness: The exchange of non-compensated benefits may therefore breed community in a way that the exchange of non-compensated harms might not. The piece being reprinted, "Of Harms and Benefits," primarily addresses the following puzzle: Why is copyright law more willing to internalize positive externalities than is the common law of restitution? Part of the answer lies in the difference in structure between the paradigmatic cases in restitution and copyright. The transaction-cost structure and autonomy implications are significantly different in the two contexts. The article also addresses the choice of "carrots" versus "sticks" as sanctions (in restitution, copyright, and personal injury torts), and offers observations on the packaging of rights, and the impact of institutional form (primarily legislature versus judiciary) on substantive rules
