What determines the strength of practical and cognitive presumptions?

This paper investigates the relationship between practical and cognitive presumptions. It argues that two types of presumptions come with different conceptions of strength. While the strength of a practical presumption is supposed to be correlated with the weight of rebuttal, the strength of a cognitive presumption is correlated with the degree of a proposition’s plausibility. However, the degree of plausibility is not necessarily correlated with the weight of the burden of rebuttal

Presumptions in argument: Epistemic versus social approaches

This paper responds to Kauffeld’s 2009 OSSA paper, considering the adequacy of his “commitment-based” approach to “ordinary presumptive practices” (which explains the communicative force of presumptions socially, through the moral motivation agents have to meet their obligations) to sup-ply an account of presumption fit for general application in normative theories of argument. The central issue here is whether socially-grounded presumptions are defeasible in the right sorts of ways so as to pro-duce “truth-tropic” presumptive inferences

Presumptions, and How They Relate to Arguments from Ignorance

By explaining the argument from ignorance in terms of the presumption of innocence, many textbooks in argumentation theory suggest that some arguments from ignorance might share essential features with some types of presumptive reasoning. The stronger version of this view, suggesting that arguments from ignorance and presumptive reasoning are almost indistinguishable, is occasionally proposed by Douglas Walton. This paper explores the nature and limits of the stronger proposal and argues that initial presumptions and arguments from ignorance are not closely connected. There are three main reasons. First, the argument from ignorance, unlike typical presumptive reasoning, is a negative kind of inference. Second, the typical initial presumption is sensitive to a broader set of defeaters and thus assumes a higher (negative) standard of acceptability. Third, in dialectical terms, initial presumption and argument from ignorance bring different attacking rights and obligations. I conclude that Waltonian intuition is unsupported or, at best, is limited only to practical presumptions and practical arguments from ignorance

Legal presumptions in the context of contemporary criminal justice. Different expressions of presumptions

Since Ancient Rome, presumption has occupied a strong position in jurisprudence. It is considered a legal category, a certain device of legal technique, which provides an opportunity to move from a known fact and its relation to other facts to an implied or supposed ‘fact’ when there is no or limited knowledge. In practice the use of presumptions helps to shorten the span of time used to solve a particular case. In such a way it saves means for the state and all the parties involved in legal procedure, and draws less on intellectual resources of participants involved in legal proceedings. Variety and prevalence of presumptions is based on three elements: social policy of the state, aspiration to optimize the law and aspiration to provide flexibility, consistency and clarity in legal relations. In nowadays jurisprudence, classification of presumptions into legal (in the narrow sense) and factual, deniable and undeniable ones are the most important because any legal presumption, in the broad sense, causes certain procedural consequences. Usually one of procedural parties gets relief from the burden of proof and upon the other one the burden is transferred (praesumptio iuris et de iure is an exception to this rule). Different presumptions serve different purposes, e.g. helping to go from a well-known fact to a supposedly known fact or to balance various potentials (opportunities) of the parties to the process in order to make them as equal as possible. This is due to the fact that the same term is used for various elements of legal technique that are of different origin and form. However, not all legal categories which fall under the term of ‘presumption’ can be recognised as being proper presumptions. In this article, while proceeding with the study of the conception of presumption,1 the meaning of presumptions is revealed, the way they are expressed is presented and, with the help of mathematical argumentation, an attempt is made to explain why iuris et de iure forms of presumptions should not fall under the category of legal presumptions

On the Differences Between Practical and Cognitive Presumptions

The study of presumptions has intensified in argumentation theory over the last years. Although scholars put forward different accounts, they mostly agree that presumptions can be studied in deliberative and epistemic contexts, have distinct contextual functions (guiding decisions vs. acquiring information), and promote different kinds of goals (non-epistemic vs. epistemic). Accordingly, there are "practical" and "cognitive" presumptions. In this paper, I show that the differences between practical and cognitive presumptions go far beyond contextual considerations. The central aim is to explore Nicholas Rescher's contention that both types of presumptions have a closely analogous pragmatic function, i.e., that practical and cognitive presumptions are made to avoid greater harm in circumstances of epistemic uncertainty. By comparing schemes of practical and cognitive reasoning, I show that Rescher's contention requires qualifications. Moreover, not only do practical and cognitive presumptions have distinct pragmatic functions, but they also perform different dialogical functions (enabling progress vs. preventing regress) and, in some circumstances, cannot be defeated by the same kinds of evidence. Hence, I conclude that the two classes of presumptions merit distinct treatment in argumentation theory

James Bradley Thayer, un precursor de la teoría de las presunciones

RESUMEN:James Bradley Thayer es habitualmente conocido en el ámbito del Derecho Constitucional por su conocido ensayo sobre el estándar del control de constitucionalidad (“The Origin and Scope of the American Doctrine of Constitutional Law” [1893]). Sin embargo, Thayer es también una de las figuras más importantes en el ámbito de la prueba en el Derecho. Este trabajo muestra la importancia de Thayer como precursor de la teoría de las presunciones en el derecho y en el razonamiento jurídico. El ensayo de Thayer sobre las presunciones, incluido en su libro A Preliminary Treatise on Evidence at the Common Law (1898), representa el locus classicus para teorizar sobre el concepto de presunción. El trabajo se divide en tres partes. En la primera parte se sitúa a Thayer en contexto. Saber quién es este autor es útil para entender mejor sus ideas. En la segunda parte se presenta la concepción de la prueba de Thayer. Finalmente, la tercera parte está dedicada a exponer la teoría de las presunciones de Thayer y a hacer um balance sobre la relevancia actual de su aportación ABSTRACT:James Bradley Thayer is traditionally known in the field of Constitutional Law for his influential essay on the standard of constitutional review (“The Origin and Scope of the American Doctrine of Constitutional Law” [1893]). However, Thayer is also one of the most outstanding figures in the Law of Evidence. This paper describes Thayer' significance as a forerunner of the theory of presumptions in Law and legal reasoning. His essay on presumptions, published in his A Preliminary Treatise on Evidence at the Common Law (1898), is the locus classics for theorizing on the concept of presumption. The paper is divided in three parts. The first part puts Thayer's thought in context. Knowing who the author is will be useful to better understand his ideas. The second part presents Thayer's conception of evidence. Finally the third part is dedicated to depict Thayer's theory of presumptions and assess the influence of his contribution today

The Presumptions of Meaning. Hamblin and Equivocation

When we use a word, we face a crucial epistemic gap: we ground our move on the fact that our interlocutor knows the meaning of the word we used, and therefore he can interpret our dialogical intention. However, how is it possible to know the other’s mind? Hamblin explained this dialogical problem advancing the idea of dialectical meaning: on his view, the use of a word is based on a set of presumptions. Building on this approach, the use of a word in a dialogue can be analyzed in terms of presumptive reasoning, while the manipulative strategies based on slanted or loaded terms or redefinitions can be conceived as forms of conflicts of presumptions. A presumptive approach to meaning can also ground different dialectical strategies to solve misunderstanding or definitional disagreements, or tactics to undermine the interlocutor’s arguments by advancing charges of equivocation