A study of symbolic logic and its usefulness to lawyers. Several descriptive and prescriptive logical systems are examined intensively. The use of these systems of logic to clarify the drafting and interpretation of legal documents is explored in a variety of contexts — statutes, contracts, judicial opinions and other writings about legal doctrine. The relationships of the logical systems to modern systems for the storage, retrieval and analysis of legal literature arealso considered. The Logical tools studied are then used to construct a formal logic of legal relations — a modernized version of Hohfeldian analysis. This modern Hohfeldian logic not only extends, modifies and refines Hohfeld’s fundamental legal conceptions, but also finally achieves his metaphorical goal of specifying “the lowest common denominators of legal discourse” for describing all legal states of affairs and changes in such states. A representation language called LEGAL RELATIONS Language, based on modern Hohfeldian logic, is constructed for use by lawyers, in analyzying legal text in judicial opinions, statutes, writings on legal doctrine and elsewhere, as well as for building computer-assisted, automatically-generated legal expert systems for interpretation assistance. No prior training in logic or mathematics is necessary.