The paper has dual aim: to analyse the structure of negligence, and to use it to offer an explanation of responsibility (for actions, omissions, consequences) in terms of the relations which must exist between the action (omission, etc.) and the agents powers of rational agency if the agent is responsible for the action. The discussion involves reflections on the relations between the law and the morality of negligence, the difference between negligence and strict liability, the role of excuses and the (...) grounds of duties to pay damages. (shrink)