Informatics and the Foundations of Legal Reasoning represents a close collaboration between a wide range of disciplines and countries. Fourteen papers, together with a long analytical introduction by the editors, were selected from the contributions of legal theorists, computer scientists, philosophers and logicians who were members of an International Working Group supported by the European Commission. The Group was mandated to work towards determining how far the law is amenable to formal modeling, and in what ways computers (...) might assist legal thinking and practice. The book is the result of discussions held by the Group over two and half years. It will help students and researchers from different backgrounds to focus on a common set of topics of increasing general interest. It embodies the results of work in progress and suggests many issues for further discussion. A stimulating text for undergraduate and graduate courses in law, philosophy and computer science departments, as well as for those interested in the place of computers in legal practice, especially at the international level. (shrink)

This paper discusses the functions of deductive justification in ideal reconstructions of judicial reasoning. It departs from the point of judicial reasoning: explaining and justifying the judicial decision. It argues that deductive validity is not enough for good judicial argument. On the other hand, deductive justification is necessary, not only for easy cases but for hard cases as well. It draws some consequences for the concept of ‘jumps’ in legal reasoning and for the traditional distinction between (...) internal and external justification. (shrink)

Reasoning with cases has been a primary focus of those working in AI and law who have attempted to model legal reasoning. In this paper we put forward a formal model of reasoning with cases which captures many of the insights from that previous work. We begin by stating our view of reasoning with cases as a process of constructing, evaluating and applying a theory. Central to our model is a view of the relationship between (...) cases, rules based on cases, and the social values which justify those rules. Having given our view of these relationships, we present our formal model of them, and explain how theories can be constructed, compared and evaluated. We then show how previous work can be described in terms of our model, and discuss extensions to the basic model to accommodate particular features of previous work. We conclude by identifying some directions for future work. (shrink)

The main aim of this paper is to study the notion of conditional right by means of constructive type theory (CTT) which provides the means to develop a system of contentual inferences rather than of syntactic derivations. Moreover, in line with Armgardt, we will first study the general notion of dependence as triggered by hypotheticals and then the logical structure of dependence specific to conditional right. I will develop this idea in a dialogical framework where the distinction between play-object and (...) strategy-object leads to the further distinction between two basic kinds of pieces of evidence and where meanings is constituted by the interaction of obligations and entitlements. The present paper is based on Rahman (2015). However, though the underlying CTT-analysis is the same, the dialogical reconstruction makes use of a new way of linking dialogical logic and CTT. Introduction. (shrink)

Fifty years of effort in artificial intelligence (AI) and the formalization of legal reasoning have produced both successes and failures. Considerable success in organizing and displaying evidence and its interrelationships has been accompanied by failure to achieve the original ambition of AI as applied to law: fully automated legal decision-making. The obstacles to formalizing legal reasoning have proved to be the same ones that make the formalization of commonsense reasoning so difficult, and (...) are most evident where legal reasoning has to meld with the vast web of ordinary human knowledge of the world. Underlying many of the problems is the mismatch between the discreteness of symbol manipulation and the continuous nature of imprecise natural language, of degrees of similarity and analogy, and of probabilities. (shrink)

A representation methodology for knowledge allowing multiple interpretations is described. It is based on the following conception of legal knowledge and its open texture. Since indeterminate, legal knowledge must be adapted to fit the circumstances of the cases to which it is applied. Whether a certain adaptation is lawful or not is measured by metaknowledge. But as this too is indeterminate, its adaptation to the case must be measured by metametaknowledge, etc. This hierarchical model of law is quite (...) well-established and may serve well as a basis for a legal knowledge system. To account for the indeterminacy of law such a system should support the construction of different arguments for and against various interpretations of legal sources. However, automatizing this reasoning fully is unsound since it would imply a restriction to arguments defending interpretations anticipated at programming time. Therefore, the system must be interactive and the user''s knowledge be furnished in a principled way. Contrary to the widespread opinion that classical logic is inadequate for representing open-textured knowledge, the framework outlined herein is given a formalization in first order logic. (shrink)

Inspired by legal reasoning, this paper presents a formal framework for assessing conflicting arguments. Its use is illustrated with applications to realistic legal examples, and the potential for implementation is discussed. The framework has the form of a logical system for defeasible argumentation. Its language, which is of a logic-programming-like nature, has both weak and explicit negation, and conflicts between arguments are decided with the help of priorities on the rules. An important feature of the system is (...) that these priorities are not fixed, but are themselves defeasibly derived as conclusions within the system. Thus debates on the choice between conflicting arguments can also be modelled.The proof theory of the system is stated in dialectical style, where a proof takes the form of a dialogue between a proponent and an opponent of an argument. An argument is shown to be justified if the proponent can make the opponent run out of moves in whatever way the opponent attacks. Despite this dialectical form, the system reflects a declarative, or relational approach to modelling legal argument. A basic assumption of this paper is that this approach complements two other lines of research in AI and Law, investigations of precedent-based reasoning and the development of procedural, or dialectical models of legal argument. (shrink)

This article proposes a formal analysis of a fundamental aspect of legal reasoning: dealing with normative conflicts. Firstly, examples are illustrated concerning the dynamics of legal systems, the application of rules and exceptions, and the semantic indeterminacy of legal sources. Then two approaches to cope with conflicting information are presented: the preferred theories of Brewka, and the belief change functions of Alchourrón, Gärdenfors, and Makinson. The relations between those approaches are closely examined, and some aspects of (...) a model of reasoning with normative conflicts are outlined. Since this model takes into account an ordering of the involved regulations, criteria to order legal norms are finally specified. (shrink)

This dissertation develops, justifies, and examines the jurisprudential implications of a non-monotonic theory of common law legal reasoning. Legal rules seem to have exceptions but identifying all of them is difficult. This hinders attempts to formalize legal rules using classical logics. Non-monotonic logics allow defeasible inference, permitting rules that hold generally but can be defeated in the presence of exceptions. This ameliorates the problem of characterizing all exceptions to a rule, because exceptions can be added piecemeal (...) while the rule remains. The first portion of the dissertation rebuts a prominent criticism leveled at a large class of theories of legal reasoning that includes my theory. The charge is that no coherent theory can recognize both the difference between distinguishing and overruling, and the constraint of precedent. The critics argue that is more important than and that can only be explained by monotonic legal rules. Drawing on cognitive psychology as well as legal theory, I show that coherent theories, such as my own, can accommodate both and. The second chapter provides motivation for understanding precedential constraint in terms of non-monotonic default rules and introduces my positive theory, which elaborates on John Horty's work in treating legal rules as prioritized defaults involving reasons. I motivate and implement a relaxation of Horty's restrictions on the form of rules to allow a more fine-grained characterization of precedent. Finally, I explore the relationship between these relaxations and the concept of precedent. The final section explains how my theory fits into the traditional jurisprudential ecosystem. I demonstrate that, contrary to assertions in the legal theory literature, this non-monotonic approach is entirely compatible with positivism's commitment to extracting rules from authoritative legal sources, namely court opinions. I also suggest how it might be attractive to law and economics theorists, pragmatists, and followers of Dworkin. (shrink)

Analogy making from examples is a central task in intelligent system behavior. A lot of real world problems involve analogy making and generalization. Research investigates these questions by building computer models of human thinking concepts. These concepts can be divided into high level approaches as used in cognitive science and low level models as used in neural networks. Applications range over the spectrum of recognition, categorization and analogy reasoning. A major part of legal reasoning could be formally (...) interpreted as an analogy making process. Because it is not the same as reasoning in mathematics or the physical sciences, it is necessary to use a method, which incorporates first the ability to specify likelihood and second the opportunity of including known court decisions. We use for modelling the analogy making process in legal reasoning neural networks and fuzzy systems. In the first part of the paper a neural network is described to identify precedents of immaterial damages. The second application presents a fuzzy system for determining the required waiting period after traffic accidents. Both examples demonstrate how to model reasoning in legal applications analogous to recent decisions: first, by learning a system with court decisions, and second, by analyzing, modelling and testing the decision making with a fuzzy system. (shrink)

The First World Congress on Evidential Legal Reasoning, organised by the Legal Culture Chair of the University of Girona, was held between June 6 and 8, 2018. The Congress was attended by 350 participants and featured 18 speakers from four continents. The three days of formal and informal presentations and discussions yielded excellent results, strengthening the interrelation between the legal communities and specialists of different traditions. The 18 papers from the Congress, reviewed by their authors based (...) on the discussions and the suggestions made at the Congress, have been compiled in this book. (shrink)

There are two possible ways to understand form and substance in legal reasoning. The first refers to the distinction between concepts and their applications, whereas the second concentrates on the difference between authoritative and non-authoritative reasons. These approaches refer to the formalistic and positivistic conceptions of the law, the latter being the author's point of departure. Nevertheless, they are both helpful means of analysis in legal interpretation. Interpretation is divided into formal and substantive justification. They have certain (...) functions and they are utilized in interaction. Authoritative reasons and formal reasoning constitute the necessary point of departure. However, substantive reasons are also necessary in order to justify choices included in interpretation. In addition to formal and substantive reasoning, the role of legal concepts is analysed. (shrink)

This collection contains studies on justice, juridical reasoning and argumenta tion which contributed to my ideas on the new rhetoric. My reflections on justice, from 1944 to the present day, have given rise to various studies. The ftrst of these was published in English as The Idea of Justice and the Problem of Argument. The others, of which several are out of print or have never previously been published, are reunited in the present volume. As justice is, for me, (...) the prime example of a "confused notion", of a notion which, like many philosophical concepts, cannot be reduced to clarity without being distorted, one cannot treat it without recourse to the methods of reasoning analyzed by the new rhetoric. In actuality, these methods have long been put into practice by jurists. Legal reasoning is fertile ground for the study of argumentation: it is to the new rhetoric what mathematics is to formal logic and to the theory of demonstrative proof. It is important, then, that philosophers should not limit their methodologi cal studies to mathematics and the natural sciences. They must not neglect law in the search for practical reason. I hope that these essays lead to be a better understanding of how law can enrich philosophical thought. CH. P. (shrink)

Illuminates legal reasoning -- and its justification At least since plato and Aristotle, thinkers have pondered the relationship between philosophical arguments and the "sophistical" arguments offered by the Sophists -- who were the first professional lawyers. Judges wield substantial political power, and the justifications they offer for their decisions are a vital means by which citizens can assess the legitimacy of how that power is exercised. However, to evaluate judicial justifications requires close attention to the method of (...) class='Hi'>reasoning behind decisions. This new collection illuminates and explains the political and moral importance in justifying the exercise of judicial power. Explores enduring questions Focusing on work over the past century, the essays address important recurring questions, such as: When a judge or a lawyer reasons to a conclusion about what is legally required in a given case, must he also ask what is morally required? To what extent do a judge's personal, political, or moral biases affect his legal reasoning? What is the impact of such biases? Can all such biases be avoided? Is legal reasoning similar to reasoning in mathematics, logic, and linguistics, the physical sciences, the social sciences, or literature and history? Do formal logical modes of argument play any roles in legal reasoning? Solid coverage, well organized The articles were chosen to present some of the most influential works on the topic, as well as less familiar works that are thought provoking and informative. Each volume also offers a representative range of theoretical approaches to its topic, contains an introduction that locates the subject within the larger framework oftheories of legal reasoning and jurisprudence, and includes bibliographical notes on further readings. Many 19th century legal theorists argued that deduction is the central mode of legal reasoning, and that legal argument is like a deductive proof in mathematics or logic. They were attracted to this "deductivist" concept because it suggested that legal reasoning could be politically and morally neutral. This volume brings together some of the most thought-provoking articles on both sides of the debate. It also contains several leading articles that explain the role of probabilistic judgments and presumptions in various types of legal arguments, including the laws of evidence and criminal procedure. The collection is a solid introduction to the basic modes of logical argument in legal reasoning. (shrink)

This paper investigates the basis arguments of so-called legal logic and their relation to logic in its standard meaning. There is no doubt that legal arguments belong to logic in the wide sense (sensu largo), but their reduction to schemes of formal logic (logica sensu stricto) is a controversial issue. It can be demonstrated that only some legal arguments fall under explicit rules of formal logic, that is, having a deductive character. Most such reasoning is fallible, (...) and its correctness depends on appealing to extra-logical principles taken from legal norms. For instance, if we say, “If it is permitted more, then it is permitted less” (argumentum a maiori ad minus), we assume that the concepts expressed by the words “more” and “less” are already defined. (shrink)

Translations of legal contracts into formal specifications that can be used for assisted reasoning are currently gaining considerable attention in AI and law. Yet, the conceptual intricacy of some of the normative notions involved in legal contracts continues to provide significant challenges to formalization; in accordance with this, there is a need for developing general logic frameworks which allow for an appropriate analysis of the fundamental components of a contractual situation. In the present work, we focus (...) on the representation of decisional and operational roles played by possibly distinct contracting parties. We provide a flexible framework, which extends term-modal logic, where such roles can be effectively formalized and emphasized. (shrink)

This paper studies the modelling of legal reasoning about evidence within general theories of defeasible reasoning and argumentation. In particular, Wigmore's method for charting evidence and its use by modern legal evidence scholars is studied in order to give a formal underpinning in terms of logics for defeasible argumentation. Two notions turn out to be crucial, viz. argumentation schemes and empirical generalisations.

La 4e de couverture indique : "The author introduces the reader to reasoning in law through the possilities, boundaries and traps of assuming personal responsibility and impersonal pattern adoption that have arisen in the history of human thought and in the various legal cultures. He discloses actual processes hidden by the veil of patterns followed in thinking, processes that we encounter both in our conceptual-logical quests for certainties and in the undertaking of fertilising ambiguity. When trying to identify (...) definitions lurking behind the human construct of facts, nitons, norms, logic, and thinking, or behind the practice of giving meanings, he discovers tradition in our presuppositions, and our world-view and moral stance in our tacit agreements. Recognising the importance of the role communication plays in shaping society, he describes our existence and institutions as self-regulating processes. Since law is a wholly social venture, we not only take part in its oeuvre with our entire personality, but are also collectively responsible for its destiny. In the final analysis, anything can be qualified as 'legal' or 'non-legal' in one or another recognised sense in which law can originate, but, as a relative totality, it can only be qualified as 'more legal' or 'less legal' in any combination of the above senses. Being formed in an uninterrupted process, neither the totality nor particular pieces of law can be taken as complete or unchangeably identical with itself. Therefore law can only be identified through its motions and computable states of 'transforming into' or 'withdrawing from' the distinctive domain of the law. Thereby both society at large and its legal professionals actually contribute to -by shaping incessantly- what presents itself as ready-to-take, according to the law's official ideology. For our initation, play, role-undertaking and human responsibility lurk behind the law's formal mask in the backstage. Or, this equals to realise that all we have become subjects from mere objects, actors from mere addressees. And despite the variety of civilisational overcoasts, the entire culture of law is still exclusively inherent in us who experience it day to day. We bear it and shape it. Everything coventional in it is convenctionalised by us. It has no further existence or effect bexond this. And with its existence inherent in us, we cannot convey the responsibility to be born for it on somebody else either. It is ours in its totality so much that it cannot be torn out of our days or acts. It will thus turn into what we guard it to become. Therefore we must take care of it at all times since we are, in many ways, taking care of our own". (shrink)

In order to represent legal knowledge adequately, it is vital to create a formal device that can freely construct an individual concept directly from a predicate expression. For this purpose, a Compound Predicate Formula (CPF) is formulated for use in legal expert systems. In this paper, we willattempt to explain the nature of CPFs by rigorous logical foundation, i.e., establishing their syntax and semantics precisely through the use of appropriate examples. We note the advantages of our system over (...) other such systems and discuss the significance of CPFs with regard to the formalization of legal reasonings using examples from the United Nations Convention for the International Sale of Goods. (shrink)

The author singles out various conceptions of rationality used in practical legal discourse: formal and substantive rationality, instrumental goal‐ and means‐rationality, communicative rationality. Practical rationality is expressed in decisions justified by epistemic and axiological premises according to the rules of justificatory reasoning. Five levels of analysis of this justification are identified. Rules, principles and evaluations are used as justifying arguments and their characteristics determine the dimensions of rationality of decision depending on the features of rules, various conceptions of (...) principles, and kinds of relativisation of evaluations. The dimensions of legal rationality depend mainly on three singled out conceptions of rationality, i.e., formal rationality dealing with the deep structure of justification, instrumentally oriented rationality as content of justifiability, and communicative rationality linked with the pragmatics of human interaction. Legitimacy, according to the presented analysis, appears as a subclass of external justification dealing with axiological premisses in terms of instrumental rationality and/or communicative rationality. (shrink)

The present article is devoted to a logical treatment of some fundamental concepts involved in responsibility attribution. We specify a theoretical framework based on a language of temporal deontic logic with agent-relative operators for deliberate causal contribution. The framework is endowed with a procedure to solve normative conflicts which arise from the assessment of different normative sources. We provide a characterization result for a basic system within this framework and illustrate how the concepts formalized can be put at work in (...) the analysis of examples of legal reasoning. (shrink)

This paper discusses a much-neglected aspect of Neil MacCormick's theory of legal reasoning, namely what he calls ‘consequential reasoning’. For MacCormick, consequential reasoning is both an omnipresent feature of legal reasoning in England and Scotland, as well as being a valuable one. MacCormick articulates the value of consequential reasoning by seeing it as contributing to the forward-looking requirement of formal justice, ie, of deciding the instant case on grounds that one is willing to (...) adopt when deciding future similar cases. This paper situates consequential reasoning in the overall picture of legal reasoning MacCormick develops in Legal Reasoning and Legal Theory, going on to show the evolution of his view on consequential reasoning in later work, which culminates in Rhetoric and the Rule of Law. It is argued that MacCormick's later view of consequential reasoning, ie, of a process of testing possible rulings by evaluating the acceptability or unacceptability.. (shrink)

Around the 1960's, C. Perelman / L. Olbrechts–Tyteca and S. Toulmin endorsed the separation between argumentation and logic. In fact, both assumed a gap between everyday reasoning, closer to legal reasoning, and scientific reasoning based on mathematics. The main claim was that both paradigms are incommensurable, since the legal paradigm makes use of the notion of formality, that has a procedural nature with roots on a conversational and dialectical practice, and logic is based on the (...) notion of form, that involves static (and syntactic) features. I will contest the incommensurability of both paradigms, as J. van Benthem (2009) did already, and plea that what we need is more rather than less logic. There are no juridical solutions to logical problems, if the problem is related to reasoning, then the solution relates to inferences drawn on the basis of juridical knowledge. (shrink)

Is the nature of law to be formal procedure or to embody substantive value? This work deals with the traditional conflict in legal philosophy between positivistic and anti-positivistic theories of law. It examines the conflict with respect to seven central issues in legal philosophy--law as a reason for action, law and authority, the internal point of view to law, the acceptance of law, discretion and principle, interpretation and semantics, and law and the common good. This work argues that (...) although this conflict cannot be resolved, the true nature of law is revealed--not obscured--by this perennial situation. (shrink)

A textbook for undergraduate, introductory logic and critical thinking courses, Principles of Logic and Reasoning: Including LSAT, GRE, and Writing Skills by Christine A. James meets a specific set of student needs. The text is engaging and readable, but also includes detailed terms, definitions, section headings, and short exercises that build a specific set of foundational logic and argumentation skills. Each key term is carefully indexed in the back of the text so that students can review easily. The text (...) includes chapters that show how logic and reasoning can be used in planning major research papers, and how logic and argumentation connects with legal reasoning and preparing for graduate level examinations that have analytic reasoning sections such as the GRE and LSAT. Often logic textbooks do not include sections on issues like these that show the relevance of logic for the average college student. This textbook is unique because it leaves students with a clear understanding that they can and will use logic to their advantage beyond their first logic course. Another advantage of this text for students is the low cost, some logic textbooks are triple the cost of this textbook. -/- For faculty members, this text has advantages as well. Each section has an exercise that is clear, concise, and adaptable to online course platforms and frequently used lecture tools like PowerPoint and Prezi. With seven chapters, the book is suited for courses that are taught in sessions of varying weeks. Many schools now offer classes in formats of 8 weeks, 10 weeks, or 16 weeks. This text is arranged with a number of chapters that can be covered in any weekly format, with sections that can be included or not included at the discretion of the instructor. Written by a faculty member at a regional state university with an emphasis on accessible undergraduate teaching, the text is written in a relaxed, conversational style so that students from diverse backgrounds will feel comfortable with the examples used. The book welcomes students to continue studying Logic in other more advanced courses. Topics covered include essential approaches to critical thinking, informal logic, fallacies, categorical logic, Venn diagrams, formal symbolic logic, first order rules of inference and replacement, as well as logic in writing and preparing for graduate school and law school. (shrink)

(2013). Legal idioms: a framework for evidential reasoning. Argument & Computation: Vol. 4, Formal Models of Reasoning in Cognitive Psychology, pp. 46-63. doi: 10.1080/19462166.2012.682656.

The challenge of calling "balls and strikes": the curious case of Gould v. Roberts -- To flatlaw and beyond : appreciating multiple analytic dimensions -- The traditions of legal reasoning : developing analytical legitimacy despite substantive disagreement -- Rethinking the analytic tradition : text, context, hypertext, and subtext -- The challenge of text : the relationship of "is," "ought," and focal meaning -- The challenge of context : what "is" means in both facts and law -- The challenge (...) of hypertext : the struggle within "ought" of multiple perspectives on fundamental values -- The challenge of subtext : considering the judiciary's role in the "game" of legal life -- The right (or rights?) to privacy (or privacies?) -- The never-ending disagreements over statutory interpretation : the primacy of subtext. (shrink)

In recent years, the most widespread doctrine about the conflicts between fundamental (usually constitutional) legal rights could be summarized in the following three main theses: (1) The elements in conflict are legal principles, as opposed to legal rules; (2) Those conflicts are not consequences of the existence of inconsistencies or antinomies between the norms involved, but rather depend on the empirical circumstances of the case. In other words, the norms are logically consistent and the conflicts are not (...) determinable a priori or in abstracto , but only in concreto ; and (3) The classical criteria for solving conflicts between norms, such as lex superior , lex posterior and lex specialis , are not suitable to solve conflicts among fundamental legal rights. Indeed, they require a specific method known as ‘weighing and balancing’. Although all three theses could be (and indeed have been) regarded as problematic, in this paper I address mainly the second one. I try to show that there is room for a tertium genus between antinomies (deontic inconsistencies) and conflicts caused by strict empirical circumstances that I call ‘contextual antinomies’. There are situations in which the norms involved are not inconsistent but the conflict arises for logical reasons. My thesis is that many conflicts between fundamental legal rights fall in this category. I offer, in an appendix, a proposal of formalization of this kind of conflict and the elements involved in it. (shrink)

In legal decisions standpoints can be supported by formal and also by substantive interpretative arguments. Formal arguments consist of reasons the weight or force of which is essentially dependent on the authoritativeness that the reasons may also have: In this connection one may think of linguistic and systemic arguments. On the other hand, substantive arguments are not backed up by authority, but consist of a direct invocation of moral, political, economic, or other social considerations. Formal arguments can be analyzed (...) as exclusionary reasons: The authoritative character excludes—in principle—substantial counterarguments. Formal arguments are sometimes used to conceal value judgements based on substantial arguments. This paper deals with reconstructing problems regarding this strategic use of formal arguments in legal decisions, with a focus on linguistic argumentation. (shrink)

This paper presents a theory of reasoning with evidence in order to determine the facts in a criminal case. The focus is on the process of proof, in which the facts of the case are determined, rather than on related legal issues, such as the admissibility of evidence. In the literature, two approaches to reasoning with evidence can be distinguished, one argument-based and one story-based. In an argument-based approach to reasoning with evidence, the reasons for and (...) against the occurrence of an event, e.g., based on witness testimony, are central. In a story-based approach, evidence is evaluated and interpreted from the perspective of the factual stories as they may have occurred in a case, e.g., as they are defended by the prosecution. In this paper, we argue that both arguments and narratives are relevant and useful in the reasoning with and interpretation of evidence. Therefore, a hybrid approach is proposed and formally developed, doing justice to both the argument-based and the narrative-based perspective. By the formalization of the theory and the associated graphical representations, our proposal is the basis for the design of software developed as a tool to make sense of the evidence in complex cases. (shrink)

The paper reconstructs Luhmann’s conception of legal argumentation and justice especially focussing on the aspects of contingency and self-referring operative closure. The aim of his conception is to describe/explain in a disenchanted way—from an external, of “second order” point of view—the work on adjudication, which, rather idealistically, lawyers and judges present as being a matter of reason. As a consequence of some surface similarities with Derrida’s deconstructive philosophy of justice, Teubner proposes integrating the supposed reductive image of formal justice (...) described by Luhmann with the ideal conception of justice presented by Derrida. Here this kind of attempt is rejected as epistemologically wrong. In addition, Luhmann’s theory is argued to have other shortcomings, namely: the failure to understand the pragmatic function of principles, and the incapacity to describe the current legal questions linked with cultures and legal pluralism, which characterise our society. (shrink)

Approximately twenty years after it was necessary to fight for human rights, the time came when it was necessary to do it again. Or to begin at the very least to protect them very strongly and thoroughly in a preventive manner. Other methods and means will revert to time when human rights were formally anchored but their material establishment is not yet realized, or not at least to the extent expected corresponding to their real substance. The beginning of the 90’s (...) in Central and Eastern Europe was a success in that human rights began to be looked on as natural, forming the basis of democratic State respecting the rule of law. Today we are increasingly more often encountering the reality that human rights, on the contrary, to the same extent that they have been able to be established, they are losing in value. The biggest danger consists in the fact that limiting of human rights often is attended by silence, without wider public discussion or deliberations. The lack of qualified discussion during the limiting of human rights by way of laws and implementing regulations is however a systemic problem. Correction of its results can be often very complex and doing away with the causes a long term effort. It is dependent on the quality of representative democracy and of the civil society as well. This article is devoted to problem of implementation of evidence of data accompanying telecommunications traffic, the so-called data retention, and in its development from lack of legal regulation to roughly unconstitutional legal regulation and finally to hope for a reasonably constitutional solution. (shrink)

I discuss the attitude of Jewish law sources from the 2nd–:5th centuries to the imprecision of measurement. I review a problem that the Talmud refers to, somewhat obscurely, as impossible reduction. This problem arises when a legal rule specifies an object by referring to a maximized measurement function, e.g., when a rule applies to the largest part of a divided whole, or to the first incidence that occurs, etc. A problem that is often mentioned is whether there might be (...) hypothetical situations involving more than one maximal value of the relevant measurement and, given such situations, what is the pertinent legal rule. Presumption of simultaneous occurrences or equally measured values are also a source of embarrassment to modern legal systems, in situations exemplified in the paper, where law determines a preference based on measured values. I contend that the Talmudic sources discussing the problem of impossible reduction were guided by primitive insights compatible with fuzzy logic presentation of the inevitable uncertainty involved in measurement. I maintain that fuzzy models of data are compatible with a positivistic epistemology, which refuses to assume any precision in the extra-conscious world that may not be captured by observation and measurement. I therefore propose this view as the preferred interpretation of the Talmudic notion of impossible reduction. Attributing a fuzzy world view to the Talmudic authorities is meant not only to increase our understanding of the Talmud but, in so doing, also to demonstrate that fuzzy notions are entrenched in our practical reasoning. If Talmudic sages did indeed conceive the results of measurements in terms of fuzzy numbers, then equality between the results of measurements had to be more complicated than crisp equations. The problem of impossible reduction could lie in fuzzy sets with an empty core or whose membership functions were only partly congruent. Reduction is impossible may thus be reconstructed as there is no core to the intersection of two measures. I describe Dirichlet maps for fuzzy measurements of distance as a rough partition of the universe, where for any region A there may be a non-empty set of - _A, where the problem of impossible reduction applies. This model may easily be combined with probabilistic extention. The possibility of adopting practical decision standards based on -cuts is discussed in this context. I propose to characterize the uncertainty that was presumably capped by the old sages as U- uncertainty, defined, for a non-empty fuzzy set A on the set of real numbers, whose -cuts are intervals of real numbers, as U = 1/h 0 h log [1+]d, where h is the largest membership value obtained by any element of A and is the measure of the -cut of A defined by the Lebesge integral of its characteristic function. (shrink)

This handbook offers a deep analysis of the main forms of legal reasoning and argumentation from both a logical-philosophical and legal perspective. These forms are covered in an exhaustive and critical fashion, and the handbook accordingly divides in three parts: the first one introduces and discusses the basic concepts of practical reasoning. The second one discusses the main general forms of reasoning and argumentation relevant for legal discourse. The third one looks at their application (...) in law as well as at the different areas of legal reasoning. The handbook’s division in three parts reflects its conceptual architecture, since legal reasoning and argumentation are considered in relation to the more general types of reasoning. (shrink)

Rationality and reasonableness can be illustrated as Janus-faced concepts, not only in a descriptive diagnosis but also in a normative construction of adjudication, and in the analysis of its practical and rhetorical effects. Considering such an illustration, the present reflection returns to the discussion on the relevance of rationality and reasonableness in legal interpretation, aiming at distinguishing and/or connecting principles and criteria, beyond formally logical and/or procedurally argumentative decision-making, and, thus, within a normatively practical adjudication. Such an approach will (...) be presented in two main steps. In a first step, the rationality/reasonableness dichotomy will be discussed within a constitutive connection between principles and criteria in adjudication, and understanding legal principles as normatively substantial foundations to legal criteria—the former as axiological references filtered into the juridical system and the latter as their concretizations, and whose practical adequacy is rhetorically assigned by the interpretive communities involved in/by adjudication, and normatively referred both to their practical accordance to the axiological normativity of the principles they shall presuppose and to their suitability as practical operators to the problematic relevance of the sub judice cases. In a second step, and consequently, encompassing the projection of legal interpretation, in semiotic and in practical-normative perspectives, in order to discuss their constituting practical relevance in adjudication, the rationality/reasonableness dichotomy will be experimented within formal-logical procedures and within practical-dialectical connections between juridical problem and juridical system—therefore stating a discussion on the foundations, the intentionality and the consequences of adjudication, amongst deduction and analogy. (shrink)

The essay discusses the import of the separability thesis both for legal positivism and for contemporary legal practice. First, the place of the separability thesis in legal positivism will be explored, distinguishing between “standard positivism” and “post‐Hartian positivism.” Then I will consider various kinds of relations between law and morality that are worthy of jurisprudential interest, and explore, from a positivist point of view, what kind of relations between law and morality must be rejected, what kind of (...) such relations should be taken into account, and what kind of such relations are indeed of no import at all. The upshot of this analysis consists in highlighting the distinction between two different dimensions of legal validity (formal validity and material validity respectively), and in pointing out that the positivist separability thesis can apply to formal validity only. On the other hand, when the ascertainment of material validity is at stake, some form of moral reasoning may well be involved (here and now, it isnecessarilyinvolved). The essay concludes with some brief remarks on the persisting importance of the positivist jurisprudential project. (shrink)

Formal models of argumentation have been investigated in several areas, from multi-agent systems and artificial intelligence (AI) to decision making, philosophy and law. In artificial intelligence, logic-based models have been the standard for the representation of argumentative reasoning. More recently, the standard logic-based models have been shown equivalent to standard connectionist models. This has created a new line of research where (i) neural networks can be used as a parallel computational model for argumentation and (ii) neural networks can be (...) used to combine argumentation, quantitative reasoning and statistical learning. At the same time, non-standard logic models of argumentation started to emerge. In this paper, we propose a connectionist cognitive model of argumentation that accounts for both standard and non-standard forms of argumentation. The model is shown to be an adequate framework for dealing with standard and non-standard argumentation, including joint-attacks, argument support, ordered attacks, disjunctive attacks, meta-level attacks, self-defeating attacks, argument accrual and uncertainty. We show that the neural cognitive approach offers an adequate way of modelling all of these different aspects of argumentation. We have applied the framework to the modelling of a public prosecution charging decision as part of a real legal decision making case study containing many of the above aspects of argumentation. The results show that the model can be a useful tool in the analysis of legal decision making, including the analysis of what-if questions and the analysis of alternative conclusions. The approach opens up two new perspectives in the short-term: the use of neural networks for computing prevailing arguments efficiently through the propagation in parallel of neuronal activations, and the use of the same networks to evolve the structure of the argumentation network through learning (e.g. to learn the strength of arguments from data). (shrink)

This handbook offers a deep analysis of the main forms of legal reasoning and argumentation from both a logical-philosophical and legal perspective. These forms are covered in an exhaustive and critical fashion, and the handbook accordingly divides in three parts: the first one introduces and discusses the basic concepts of practical reasoning. The second one discusses the main general forms of reasoning and argumentation relevant for legal discourse. The third one looks at their application (...) in law as well as at the different areas of legal reasoning. The handbook’s division in three parts reflects its conceptual architecture, since legal reasoning and argumentation are considered in relation to the more general types of reasoning. (shrink)

In this article we introduce a logical structure for normative reasoning, called Normative Detachment Structure with Ideal Conditions, that can be used to represent the content of certain legal texts in a normalized way. The structure exploits the deductive properties of a system of bimodal logic able to distinguish between ideal and actual normative statements, as well as a novel formalization of conditional normative statements able to capture interesting cases of contrary-to-duty reasoning and to avoid deontic (...) paradoxes. Furthermore, we illustrate how the theoretical framework proposed can be mechanized to get an automated procedure of query-answering on an example of legal text. (shrink)

The concept of legal gap is tackled from a number of logical perspectives and semantic methods. After presenting our own goal (Section 1), a first introduction into legal logic refers to Bobbio’s works and his formalization of legal statements (Sections 2 and 3). Then Woleński’s contribution to the area is taken into account through his reference to the distinction between two juridical systems (viz. Common Law vs Civil Law) and the notion of conditional norms (Section 4). (...) The notion of reason is also highlighted in the case of Raz’s legal logic, thereby leading to a future connection with von Wright’s logic of truth and an analogy made with an anti-realist reading of truth-values and norms (Section 5). Our personal contribution is introduced through a reflection on how logic should deal with the logical form of norms (Section 6), before entering a number of crucial definitions and distinctions for the concepts of norm, legal statement, and promulgation (Section 7). The final point is a proposed semantics for legal statements, which is both many-valued and gap-friendly (Section 8). A distinction between a number of requirements for permission and forbiddance leads to a set of non-classical juridical systems in which non-permission and forbiddance are not equivalent with each other any more; this does justice to Woleński’s former distinction between Common Law and Civil Law, also leading ultimately to a non-classical square of legal oppositions in which several legal operators may collapse into other ones (Section 9). (shrink)

This paper analyses some current jurisprudential and conceptual issues in evidence and procedure from the perspective of a computational legal theory. It introduces a specific investigative device, Trojans operated by police during crime investigation, and analyses whether current formal approaches to legal reasoning can be modified in such a way that the software code underlying this device can represent the relevant legal constraints that should govern its operation. We will argue that traditional formalist theories of (...) class='Hi'>legal reasoning are typically restricted to reasoning within a system, and incapable therefore of making the notion of “legal system” sufficiently explicit. We discuss possibilities to expand on these approaches and identify the necessary elements of a computational theory of legal reasoning in an age of porous borders.Resumen:En este ensayo se analizan algunos tópicos conceptuales y filosóficos de actualidad sobre el procedimiento y las pruebas desde la óptica de una teoría del derecho computacional. En él se presenta un mecanismo específico de investigación, relativo a los “troyanos” operados por la policía durante la investigación de delitos, y analiza si los enfoques formales contemporáneos sobre el razonamiento jurídico pueden ser modificados de tal modo que el código de sofware que subyace a este mecanismo puede representar las limitaciones jurídicas relevantes que deberían regir su operación. Los autores sostienen que las teorías formalistas tradicionales del razonamiento jurídico se limitan por lo general al razonamiento dentro de un sistema y, por lo tanto, son incapaces de hacer la noción de “sistema jurídico” suficientemente explícita. Asimismo, se discuten las posibilidades de ampliar estos enfoques e identificar los elementos necesarios de una teoría computacional del razonamiento jurídico en una era de fronteras porosas. (shrink)

The article considers two different interpretations of the reason model of precedent pioneered by John Horty. On a plausible interpretation of the reason model, past cases provide reasons to prioritize reasons favouring the same outcome as a past case over reasons favouring the opposing outcome. Here I consider the merits of this approach to the role of precedent in legal reasoning in comparison with a closely related view favoured by some legal theorists, according to which past cases (...) provide reasons for undercutting (or ‘excluding’) reasons favouring the opposing outcome. After embedding both accounts within a general default logic, I note some important differences between the two approaches that emerge as a result of plausible distinctions between rebutting and undercutting defeat in formal models of legal reasoning. These differences stem from the ‘preference independence’ of undercutting defeat. Undercutting reasons succeed in defeating opposing reasons irrespective of their relative strength. As a result, the two accounts differ in their account of the way in which precedents constrain judicial reasoning. I conclude by suggesting that the two approaches can be integrated within a single model, in which the distinction between undercutting and rebutting defeat is used to account for the distinction between strict and persuasive forms of precedential constraint. (shrink)

This paper describes a model of legal reasoning and a logic for reasoning with rules, principles and goals that is especially suited to this model of legal reasoning. The paper consists of three parts. The first part describes a model of legal reasoning based on a two-layered view of the law. The first layer consists of principles and goals that express fundamental ideas of a legal system. The second layer contains legal (...) rules which in a sense summarise the outcome of the interaction of the principles and goals for a number of case types. Both principles, goals and rules can be used in legal arguments, but their logical roles are different. One characteristic of the model of legal reasoning described in the first part of the paper is that it takes these logical differences into account. Another characteristic is that it pays serious attention to the phenomena of reasoning about the validity and acceptance of rules, respectively principles and goals, and about the application of legal rules, and the implications of these arguments for the use of rules, principles and goals in deriving legal conclusions for concrete cases.The second part of the paper first describes a logic (Reason-Based Logic) that is especially suited to deal with legal arguments as described in terms of the previously discussed model. The facilities of the logic are illustrated by means of examples that correspond to the several aspects of the model. (shrink)

PurposeThe purpose of this paper is to profile everyday management and business strategies of 30 cyber cafés in Mumbai and contextualize them in the broader and pervasive culture of non‐formal economy.Design/methodology/approachThe paper conducts an ethnographic study of open‐ended interviews of cyber café owner/managers to understand everyday patterns of managing a cyber café. The field observations and literature review aid an understanding of non‐formal economy in Mumbai.FindingsThe paper finds three important insights: business with internet technologies, even at the level of a (...) small café, is expensive, requiring reasonable computing skills to maintain or expand business potential; in order to survive expense management several unauthorized practices are routinised and merge with the broader structures of non‐formal economy; and the non‐formality of business practices influence an open, liberal atmosphere to browse the internet and turn in a predominantly youth clientele.Research limitations/implicationsWith regulatory discourse on information and communication technologies centered on piracy and ill‐legality, informality of business practices in emerging economies provide an alternate premise to understand its nature and function. These challenge received notions of visualizing ICT as simply piracy and coming to terms with markets shaped and structured by non‐formal processes.Originality/valueThe study is one of the first on cyber cafés in Mumbai using the framework of non‐formal economy to analyse data. This paper presents the connections between a small ICT‐enabled business and the pervasive culture of non‐formal business relations in Mumbai. It also reports on the everyday organizational practices and client usages of internet cafés in India. (shrink)

This article describes the Vaccine/Injury Project Corpus, a collection of legal decisions awarding or denying compensation for health injuries allegedly due to vaccinations, together with models of the logical structure of the reasoning of the factfinders in those cases. This unique corpus provides useful data for formal and informal logic theory, for natural-language research in linguistics, and for artificial intelligence research. More importantly, the article discusses lessons learned from developing protocols for manually extracting the logical structure and generating (...) the logic models. It identifies sub-tasks in the extraction process, discusses challenges to automation, and provides insights into possible solutions for automation. In particular, the framework and strategies developed here, together with the corpus data, should allow “top–down” and contextual approaches to automation, which can supplement “bottom-up” linguistic approaches. Illustrations throughout the article use examples drawn from the Corpus. (shrink)

This book discusses theories of legal reasoning and provides an overall view of the rhetoric of legal justification. It shows how and why lawyers arguments can be rationally persuasive even though rarely, if ever, logically conclusive or compelling. It examines the role of "legal syllogism" and universality of legal reasoning, looking at arguments of consequentialism and principle, and concludes by questioning the infallibility of judges as lawmakers.

Photomechanical reprint of papers from 1970 to 1992 mostly in English, some in German or French: Foreword 1–4; LAW AS PRACTICE ‘La formation des concepts en sciences juridiques’ 7–33, ‘Geltung des Rechts – Wirksamkeit des Rechts’ 35–42, ‘Macrosociological Theories of Law’ 43–76, ‘Law & its Inner Morality’ 77–89, ‘The Law & its Limits’ 91–96; LAW AS TECHNIQUE ‘Domaine »externe« & domaine »interne« en droit’ 99–117, ‘Die ministerielle Begründung’ 119–139, ‘The Preamble’ 141–167, ‘Presumption & Fiction’ 169–185, ‘Legal Technique’187–198; LAW AS (...) LOGIC ‘Moderne Staatlichkeit und modernes formales Recht’ 201–207, ‘Heterogeneity & Validity of Law’ 209–218, ‘Leibniz & die Frage der rechtlichen Systembildung’ 219–232, ‘Law & its Approach as a System’ 233–255, ‘Logic of Law & Judicial Activity’ 258–288, ‘Kelsen’s Pure Theory of Law’ 289–293, ‘The Nature of the Judicial Application of Norms’ 295–314; LAW AS EXPERIENCE ‘The Socially Determined Nature of Legal Reasoning’317–374, ‘The Ontological Foundation of Law’ 375–390, ‘Is Law a System of Enactments?’ 391–398, ‘The Uniqueness of National Legal Cultures’ 399–411, ‘Institutions as Systems’ 413–424; LAW AS HISTORY ‘From Legal Customs to Legal Folkways’ 427–436, ‘Anthropological Jurisprudence?’ 437–457, ‘Law as a Social Issue’ 459–475, ‘Law as History?’477–484, ‘Rechtskultur – Denkkultur’ 485–489; w/ Curriculum Vitae & Bibliography, as well as Index & Indexes of normative materials & of names. (shrink)