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William & Mary Law Review

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Thanks to Richard Posner's classic 1972 article, A Theory of Negligence Law, the Hand formula of United States. v. Carroll Towing Co. is perhaps the most central idea of many first-year torts classes today. Students learn that the meaning of negligence should be understood in terms of Judge Learned Hand's formula comparing the costs of taking precautions with the product of the likelihood of injury without those precautions and the magnitude of such injury. There is more than a little irony, however, in the superstar status of the Hand formula in negligence law. Carroll Towing is not a negligence case at all; indeed, it is not even a tort case, but an admiralty case. Beyond that, even the very general idea of a negligent injurer being held liable for the injuries it caused is not implicated in Carroll Towing, because it is about plaintiff's fault, not defendant's fault. Posner's elevation of this formula to the apex of negligence doctrine is, though utterly sincere, nevertheless a sleight of Hand. This article puts aside the moral and evaluative arguments that frequently divide tort theorists, and instead gathers overwhelming evidence within negligence law that the Hand formula - in both its economic and its non-economic versions - simply misses the meaning of negligence within negligence doctrine. Negligence is a failure to use ordinary care. Ordinary care is that which a reasonably prudent person would use under the circumstances. While hardly self-evident or precise, concepts of ordinary care and the reasonably prudent person connote a standard of conduct that our negligence doctrine requires jurors and judges to apply as well as they can. There is every reason to believe this meaning is something quite different from the Hand formula (even if the two ideas should sometimes overlap). An accurate account of the meaning of negligence is a necessary starting point for questions or interpretation, criticism, and revision of tort doctrine. Finally, the article canvasses and rejects rights-based, conventionalistic, and virtue-based theories of the meaning of negligence, and begins to sketch an account according to which the reasonably prudent person is conceived in terms of a special kind of competency in civil life.