This book tackles the basics of legal reasoning in twelve chapters, including the principles of classic logic, deductive and inductive reasoning, application of the Socratic method to legal reasoning, and formal and material fallacies.

Have you ever read a legal opinion and come across an odd term like the fallacy of denying the antecedent, the fallacy of the undistributed middle, or the fallacy of the illicit process and wondered how you missed that in law school? You’re not alone: every day, lawyers make arguments that fatally trespass the rules of formal logic—without realizing it—because traditional legal education often overlooks imparting the practical wisdom of ancient philosophy as it teaches students how to “think like a lawyer.” In his book, The Force of Logic: Using Formal Logic as a Tool in the Craft of Legal Argument, lawyer and law professor Stephen M. Rice guides you to develop your powers of legal reasoning in a new way, through effective tips and tactics that will forever change the way you argue your cases. Rice contends that formal logic provides tools that help lawyers distinguish good arguments from bad ones and, moreover, that they are simple to learn and use. When you know how to recognize logical fallacies, you will not only strengthen your own arguments, but you will also be able to punch holes in your opponent’s—and that can make the difference between winning and losing. In this book, Rice builds on the theoretical foundation of formal logic by demonstrating logical fallacies through the use of anecdotes, examples, graphical illustrations, and exercises for you to try that are derived from common case documents. It is a hands-on primer that presents a practical approach for understanding and mastering the place of formal logic in the art of legal reasoning. Whether you are a lawyer, a judge, a scholar, or a student, The Force of Logic will inspire you to love legal argument, and appreciate its beauty and complexity in a brand new way.

The study presented in this book was entered upon by me from a legal point of view. 'Legal logic' has been known for a long time, concerning itself with the methodology of legal and in particular judicial reasoning. In modern days, however, this 'legal logic' is sometimes also connected with modern formal logic, as it has been developed in the works of G. Boole, A. de Morgan, G. Frege, C.S. Peirce, E. Schroder, G. Peano, A.N. Whitehead, B. Russell and others. For me this gave rise to the as yet not very specific question about the meaning of modern symbolic logic for law. Already in an early stage it appeared that, although traditional legal logic and modern symbolic logic both concern logic, this may not create the misapprehension that a similar matter is at issue. Both concern themselves (among other things) with reasonings and reasoning. Traditional legal logic is, however, as it was said by the German legal theoretician K. Engisch: "a material logic that wants us to reflect on what we have to do if we -within the limits of actual possibility- wish to reach true, or at least correct judgements" (Engisch, 1964, p.5). Modern symbolic logic on the other hand is not concerned with the truth or correctness of the result of an argument, but with its validity, i.e. the question when or under which conditions the truth (correctness) of the conclusion is guaranteed by the truth (correctness) of the premisses.

Provides an essential introduction to classical logic.

Rule-applying legal arguments are traditionally treated as a kind of syllogism. Such a treatment overlooks the fact that legal principles and rules are not statements which describe the world, but rather means by which humans impose structure on the world. Legal rules create legal consequences, they do not describe them. This has consequences for the logic of rule- and principle-applying arguments, the most important of which may be that such arguments are defeasible. This book offers an extensive analysis of the role of rules and principles in legal reasoning, which focuses on the close relationship between rules, principles, and reasons. Moreover, it describes a logical theory which assigns a central place to the notion of reasons for and against a conclusion, and which is especially suited to deal with rules and principles.

Studies in Legal Logic is a collection of nine interrelated papers about the logic, epistemology and ontology of law. All of the papers were written after the publication of the author’s Reasoning with Rules and supplement the issues addressed therein. Some of the papers are new; others have been revised substantially after the publication of their original versions. The emphasis is on analysis, not on logical technicalities. Studies in Legal Logic contains chapters about the nature of norms, the role of coherence in the law, the nature of defeasibility, the role of dialectics in law and artificial intelligence, the statics and dynamics of the law, and the consistency of rules. Moreover, it contains a new, simplified and yet more powerful version of Reason-based Logic and extensive examples of how it can be used for the analysis of legal reasoning. The examples deal with legal theory construction, case-based reasoning, and judicial proof.

This book intends to unite studies in different fields related to the development of the relations between logic, law and legal reasoning. Combining historical and philosophical studies on legal reasoning in Civil and Common Law, and on the often neglected Arabic and Talmudic traditions of jurisprudence, this project unites these areas with recent technical developments in computer science. This combination has resulted in renewed interest in deontic logic and logic of norms that stems from the interaction between artificial intelligence and law and their applications to these areas of logic. The book also aims to motivate and launch a more intense interaction between the historical and philosophical work of Arabic, Talmudic and European jurisprudence. The publication discusses new insights in the interaction between logic and law, and more precisely the study of different answers to the question: what role does logic play in legal reasoning? Varying perspectives include that of foundational studies (such as logical principles and frameworks) to applications, and historical perspectives.