The modern lawyer operates within a conception of law as a body of rules. To confront the law of contract, of torts, or of property, is to familiarize oneself with an intricate set of rules. Such familiarity is not yet legal scholarship, much less legal practice. For in order to use the rules as lawyers use them, the rules must be contemplated and considered, and the relationship between the different rules must be understood. Because the intellectual processes involved in handling the rules exhibit a high degree of sophistication, those intellectual processes may themselves become the subject matter of philosophical argument. Thus we may regard jurisprudential theories as embodying differing understandings of the processes of handling legal rules; and we may conceive of legal theory as the attempt to grasp the moral significance of rules as a foundation for social order. This essay shall offer some thoughts on the relationship between the rule of law, considered as a moral ideal, and the notion of rules as the principal means by which legal order is manifested.