Logic or rhetoric in law?

One of the most crucial questions in the philosophy of law deals with the very nature of legal reasoning. Does this reasoning belong to logic or to rhetoric? This debate, increasingly centered on rhetoric, is not merely a question of language use; it covers and indicates a more basic choice between formal legalism — focusing on rational deduction from the law — and pragmatic judiciarism — focusing on reasonable debate in the court. Today, it is necessary to circumscribe the respective fields of logic and rhetoric in the language of law, while showing how they are sometimes complementary in the resolution of legal problems. But, even when we have acknowledged the need for a rhetoric accompanied by logic, we have to define that rhetoric cautiously. I confront a narrow rhetoric, often called argumentation, with a wider one of interrogative nature. There are two conceptions of rationality at stake. Their comparison enables us to raise the question of the foundation of law, as a locus to use arguments, as well as to solve social problems.     

Formalization of the ad hominem argumentation scheme

In this paper, several examples from the literature, and one central new one, are used as case studies of texts of discourse containing an argumentation scheme that has now been widely investigated in literature on argumentation. Argumentation schemes represent common patterns of reasoning used in everyday conversational discourse. The most typical ones represent defeasible arguments based on nonmonotonic reasoning. Each scheme has a matching set of critical questions used to evaluate a particular argument fitting that scheme. The project is to study how to build a formal computational model of this scheme for the circumstantial ad hominem argument using argumentation tools and systems developed in artificial intelligence. It is shown how the formalization built using these tools is applicable to the tasks of identification, analysis and evaluation of the central case studied. One important implication of the work is that it provides a foundational basis for showing how other argumentation schemes can be formalized.     

Foundations of Everyday Practical Reasoning

“Since today is Saturday, the grocery store is open today and will be closed tomorrow; so let’s go today”. That is an example of everyday practical reasoning—reasoning directly with the propositions that one believes but may not be fully certain of. Everyday practical reasoning is one of our most familiar kinds of decisions but, unfortunately, some foundational questions about it are largely ignored in the standard decision theory: (Q1) What are the decision rules in everyday practical reasoning that connect qualitative belief and desire to preference over acts? (Q2) What sort of logic should govern qualitative beliefs in everyday practical reasoning, and to what extent is that logic necessary for the purposes of qualitative decisions? (Q3) What kinds of qualitative decisions are always representable as results of everyday practical reasoning? (Q4) Under what circumstances do the results of everyday practical reasoning agree with the Bayesian ideal of expected utility maximization? This paper proposes a rigorous decision theory for answering all of those questions, which is developed in parallel to Savage’s (1954) foundation of expected utility maximization. In light of a new representation result, everyday practical reasoning provides a sound and complete method for a very wide class of qualitative decisions; and, to that end, qualitative beliefs must be allowed to be closed under classical logic plus a well-known nonmonotonic logic—the so-called system ?.     

Evaluating Dialectical Structures

This paper develops concepts and procedures for the evaluation of complex debates. They provide means for answering such questions as whether a thesis has to be considered as proven or disproven in a debate or who carries a burden of proof. While being based on classical logic, this framework represents an (argument-based) approach to non-monotonic, or defeasible reasoning. Debates are analysed as dialectical structures, i.e. argumentation systems with an attack- as well as a support-relationship. The recursive status assignment over the arguments is conditionalised on proponents in a debate. The problem of multiple status assignments arising on circular structures is solved by showing that uniqueness can be guaranteed qua reconstruction of a debate. The notion of burden of proof as well as other discursive aims rational proponents pursue in a debate is defined within the framework.     

Reflective Argumentation: A Cognitive Function of Arguing

Why do we formulate arguments? Usually, things such as persuading opponents, finding consensus, and justifying knowledge are listed as functions of arguments. But arguments can also be used to stimulate reflection on one’s own reasoning. Since this cognitive function of arguments should be important to improve the quality of people’s arguments and reasoning, for learning processes, for coping with “wicked problems,” and for the resolution of conflicts, it deserves to be studied in its own right. This contribution develops first steps towards a theory of reflective argumentation. It provides a definition of reflective argumentation, justifies its importance, delineates it from other cognitive functions of argumentation in a new classification of argument functions, and it discusses how reflection on one’s own reasoning can be stimulated by arguments.     

Solving a Murder Case by Asking Critical Questions: An Approach to Fact-Finding in Terms of Argumentation and Story Schemes

In this paper, we look at reasoning with evidence and facts in criminal cases. We show how this reasoning may be analysed in a dialectical way by means of critical questions that point to typical sources of doubt. We discuss critical questions about the evidential arguments adduced, about the narrative accounts of the facts considered, and about the way in which the arguments and narratives are connected in an analysis. Our treatment shows how two different types of knowledge, represented as schemes, play a role in reasoning with evidence: argumentation schemes and story schemes.     

Practical Reasoning Arguments: A Modular Approach

This paper compares current ways of modeling the inferential structure of practical (goal-based) reasoning arguments, and proposes a new approach in which it is regarded in a modular way. Practical reasoning is not simply seen as reasoning from a goal and a means to an action using the basic argumentation scheme. Instead, it is conceived as a complex structure of classificatory, evaluative, and practical inferences, which is formalized as a cluster of three types of distinct and interlocked argumentation schemes. Using two real examples, we show how applying the three types of schemes to a cluster of practical argumentation allows an argument analyst to reconstruct the tacit premises presupposed and evaluate the argumentative reasoning steps involved. This approach will be shown to overcome the limitations of the existing models of practical reasoning arguments within the BDI and commitment theoretical frameworks, providing a useful tool for discourse analysis and other disciplines. In particular, applying this method brings to light the crucial role of classification in practical argumentation, showing how the ordering of values and preferences is only one of the possible areas of deep disagreement.     

Analogy Counterarguments: A Taxonomy for Critical Thinking

The presentation of analogical arguments in the critical thinking literature fails to reflect cognitive research on analogy. Part of the problem is that these treatments of analogy do not address counterarguments, an important aspect of the analysis of analogical argumentation. In this paper, I present a taxonomy of four counterarguments, false analogy, misanalogy, disanalogy, and counteranalogy, analyzed along two dimensions, orientation and effect. The counterarguments are treated in the framework of the multiconstraint theory of analogy (Holyoak and Thagard, 1995). This framework is also extended to account for the evidence brought to light by the consideration of counterarguments. The result is a psychologically motivated treatment of analogical arguments that will be useful both for critical and pedagogical purposes.     

A neural cognitive model of argumentation with application to legal inference and decision making

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).     

Towards a Richer Debate on Tissue Engineering: A Consideration on the Basis of NEST-Ethics

In their 2007 paper, Swierstra and Rip identify characteristic tropes and patterns of moral argumentation in the debate about the ethics of new and emerging science and technologies (or “NEST-ethics”). Taking their NEST-ethics structure as a starting point, we considered the debate about tissue engineering (TE), and argue what aspects we think ought to be a part of a rich and high-quality debate of TE. The debate surrounding TE seems to be predominantly a debate among experts. When considering the NEST-ethics arguments that deal directly with technology, we can generally conclude that consequentialist arguments are by far the most prominently featured in discussions of TE. In addition, many papers discuss principles, rights and duties relevant to aspects of TE, both in a positive and in a critical sense. Justice arguments are only sporadically made, some “good life” arguments are used, others less so (such as the explicit articulation of perceived limits, or the technology as a technological fix for a social problem). Missing topics in the discussion, at least from the perspective of NEST-ethics, are second “level” arguments—those referring to techno-moral change connected to tissue engineering. Currently, the discussion about tissue engineering mostly focuses on its so-called “hard impacts”—quantifiable risks and benefits of the technology. Its “soft impacts”—effects that cannot easily be quantified, such as changes to experience, habits and perceptions, should receive more attention.     

Some Artificial Intelligence Tools for Argument Evaluation: An Introduction

Even though tools for identifying and analyzing arguments are now in wide use in the field of argumentation studies, so far there is a paucity of resources for evaluating real arguments, aside from using deductive logic or Bayesian rules that apply to inductive arguments. In this paper it is shown that recent developments in artificial intelligence in the area of computational systems for modeling defeasible argumentation reveal a different approach that is currently making interesting progress. It is shown how these systems provide the general outlines for a system of argument evaluation that can be applied to legal arguments as well as everyday conversational arguments to assist a user to evaluate an argument.     

Analogical Reasoning in Ethics

In this article I am concerned with analogical reasoning in ethics. There is no doubt that the use of analogy can be a powerful tool in our ethical reasoning. The importance of this mode of reasoning is therefore commonly accepted, but there is considerable debate concerning how its structure should be understood and how it should be assessed, both logically and epistemically. In this paper, I first explain the basic structure of arguments from analogy in ethics. I then discuss the diversity of analogical arguments that can be found in ethics. I analyse their structure, assess them from a logical viewpoint, and show how they can be epistemically challenged and defended. The result of this investigation is that, contrary to a commonly held view, analogical reasoning can be a logically valid type of ethical reasoning that can provide reasons for action that are not worse than the reasons provided by any other kind of practical reasoning.     

Argumentation Without Arguments

A well-known ambiguity in the term ‘argument’ is that of argument as an inferential structure and argument as a kind of dialogue. In the first sense, an argument is a structure with a conclusion supported by one or more grounds, which may or may not be supported by further grounds. Rules for the construction and criteria for the quality of arguments in this sense are a matter of logic. In the second sense, arguments have been studied as a form of dialogical interaction, in which human or artificial agents aim to resolve a conflict of opinion by verbal means. Rules for conducting such dialogues and criteria for their quality are part of dialogue theory. Usually, formal accounts of argumentation dialogues in logic and artificial intelligence presuppose an argument-based logic. That is, the ways in which dialogue participants support and attack claims are modelled as the construction of explicit arguments and counterarguments (in the inferential sense). However, in this paper formal models of argumentation dialogues are discussed that do not presuppose arguments as inferential structures. The motivation for such models is that there are forms of inference that are not most naturally cast in the form of arguments (such as abduction, statistical reasoning and coherence-based reasoning) but that can still be the subject of argumentative dialogue. Some recent work in artificial intelligence is discussed which embeds non-argumentative inference in an argumentative dialogue system, and some general observations are drawn from this discussion.     

Disentangling Critical Questions from Argument Schemes

Critical questions have been understood in the framework of argument schemes from their conception. This understanding has influenced the process of evaluating arguments and the development of classifications. This paper argues that relating these two notions is detrimental to research on argument schemes and critical questions, and that it is possible to have critical questions without relying on argument schemes. Two objections are raised against the classical understanding of critical questions based on theoretical and analytical grounds. The theoretical objection presents the assumptions that are embedded in the idea of argument schemes delivering questions to evaluate arguments. The analytical objection, on the other hand, exposes the shortcomings of the theory when critical questions are used to evaluate real-life argumentation. After presenting these criticisms, a new theory of critical questions is sketched. This theory takes into account the dynamics of dialectical discussions to describe the function of critical questions and their implications for evaluating arguments.

     

On the Special Logic Thesis in Chinese Philosophy

I address the problem of whether philosophy can be international by its claim to represent rationality, hence universality. I argue in favor of this claim by focusing on the special logic thesis in Chinese philosophy. This thesis holds that a different type of logic must be used when studying the Chinese texts. I argue at length against the special logic thesis by examining the problem of human nature in the Confucian philosophers Mencius, Hsün Tzu and Kao Tzu. I show how their arguments can be reconstructed as inductive analogical arguments and as deductive argument. I then broaden the notion of the logic of argumentation into a discussion of metaphysical anti-essentialism and underdetermination in order to resolve the problem of human nature and also to show how the same types of logical analysis (more generally construed) can be applied to the arguments from these Confucian philosophers. Under my treatment, Kao Tzu, somewhat surprisingly, turns out to provide the most insight.     

Argumentation and Fallacy in the Justification of the 2003 War on Iraq

The present study examined how the pre-war debate of the US decision to invade Iraq (in March 2003) was discursively constructed in the US/British mainstream newspaper opinion/editorial (op/ed) argumentation. Drawing on theoretical insights from critical discourse analysis and argumentation theory, I problematised the fallacious discussion used in the pro-war op/eds to build up a ‘moral/legal case’ for war on Iraq based on adversarial (rather than dialogical) argumentation. The proponents of war deployed ‘instrumental rationality’ (ends-justify-means reasoning), ‘ethical necessity’ (Bush’s ‘Preemption Doctrine’) and ‘humanitarian virtue’ (the bombing of Iraq to ‘save’ Iraqis from Saddam’s pestilent tyranny) to justify the pending invasion of Iraq. Their arguments intertextually resonated with Bush administration’s ‘war on terror’ rhetoric in a way that created a form of indexical association through ‘recontextualisation’. The type of arguments marshalled by the pro-war op/ed commentators uncritically bolstered the set of US official ‘truth claims’ and ‘presuppositions’.     

Abstract argumentation and explanation applied to scientific debates

Abstract argumentation has been shown to be a powerful tool within many fields such as artificial intelligence, logic and legal reasoning. In this paper we enhance Dung’s well-known abstract argumentation framework with explanatory capabilities. We show that an explanatory argumentation framework (EAF) obtained in this way is a useful tool for the modeling of scientific debates. On the one hand, EAFs allow for the representation of explanatory and justificatory arguments constituting rivaling scientific views. On the other hand, different procedures for selecting arguments, corresponding to different methodological and epistemic requirements of theory evaluation, can be formulated in view of our framework.     

A Defense of Conduction: A Reply to Adler

In (2013) Jonathan Adler argued that conductive arguments, as they are commonly characterized, are impossible—that no such argument can exist. This striking contention threatens to undermine a topic of argumentation theory originated by Trudy Govier (1979) based on Carl Wellman (1971) and revisited by the papers in “Conductive argument, An overlooked type of defeasible reasoning” (ed. Blair and Johnson, 2011). I here argue that Adler’s dismissal of conductive arguments relies on a misreading of the term ‘non-conclusive’ used in the characterization of this type of reasoning and argument, and that as a result, his refutation fails. However, Adler’s critique raises other questions about conductive arguments that have to be answered.     

Towards Formal Representation and Evaluation of Arguments

The aim of this paper is to propose foundations for a formal model of representation and numerical evaluation of a possibly broad class of arguments, including those that occur in natural discourse. Since one of the most characteristic features of everyday argumentation is the occurrence of convergent reasoning, special attention should be paid to the operation ⊕, which allows us to calculate the logical force of convergent arguments with an accuracy not offered by other approaches.