 First: human law, unlike the “natural law” of morality, is inherently parochial in the sense that human law varies from place to place. (It does this because human law’s existence depends in part upon facts of institutional history and these facts vary from place to place.) So the question, “whose law?”, looms large at the start of an enquiry such as this. What follows describes causation as it is used in what may broadly be called the Anglo-American legal tradition—the legal tradition of the United Kingdom, the domains of its Commonwealth, and the United States. Despite this confession of a somewhat parochial focus, there are nonetheless universalist implications of this analysis. This is because there are strong similarities in the legal uses of causation in all presently existing legal systems, even when one is not confined to those of the English-speaking world. 