At the end of the last chapter, I suggested that the idea that a distribution can be justified by the process that produced it is too important to be left with libertarians. This chapter fills out one element of that idea by offering an alternative to strict liability in tort. The libertarian concern with strict liability arose out of the recognition that an account of justice that treats voluntary transactions as justice-preserving requires a way of undoing wrongful changes. The point of an historical account is that not all changes to a pattern of holdings disturb its justice. But some do. Thus, an account of fair terms of interaction must specify which changes need to be remedied, and the appropriate remedy when those changes occur.

Negligence is the primary basis of tort liability in Anglo-American legal systems. Negligence liability serves to undo those losses that result from a failure to take appropriate care. The intuitive idea is that my responsibility for my negligence extends only to the negligent aspects of my conduct. In failing to live up to a standard of care, I act as though the legally protected interests of others are mere things. In so doing, I make the risk to them part of my agency. Because the risk is mine, and whether or not it ripens is a matter of causation, causation fixes both the existence and extent of my liability.