The present paper elaborates a deductivist account of natural language argu-ment in the context of pragma-dialectics. It reviews earlier debates, criticizes some standard misconceptions in the literature, and argues that the identification and analysis of deductive argument schemes can be the basis of a compelling theory of argumentative discourse.

Deductivism has been variously presented as an evaluative thesis and as an interpretive one. I argue that deductivism fails as a universal evaluative thesis, and as such that its value as an interpretive thesis must be supported on other grounds. As a reconstructive strategy, deductivism is justified only on the grounds that an arguer is, or ought to be, aiming at the deductive standard of evidence. As such, the reconstruction of an argument as deductive must be supported (...) by contextual and situational factors including facts about the arguer. Further, the plausibility of deductivism as a normative thesis is not tied to its plausibility as a descriptive or interpretive thesis. (shrink)

This essay proposes and defends a general thesis concerning the nature of fallacies of reasoning. These in distinctive ways are all said to be deductively invalid. More importantly, the most accurate, complete and charitable reconstructions of these species and specimens of the informal fallacies are instructive with respect to the individual character of each distinct informal fallacy. Reconstructions of the fallacies as deductive invalidities are possible in every case, if deductivism is true, which means that in every case they (...) should be formalizable in an expressively comprehensive formal symbolic deductive logic. The general thesis is illustrated by a detailed examination of Walter Burleigh's paradox in his c. 1323 work, De Puritate Artis Logicae Tractatus Longior (Longer Treatise on the Purity of Logic), as a challenge to the deductive validity of hypothetical syllogism. The paradox has the form, ‹If I call you a swine, then I call you an animal; if I call you an animal, then I speak truly; therefore, if I call you a swine, then I speak truly'. Several solutions to the problem are considered, and the inference is exposed as an instance of the common deductive fallacy of equivocation. (shrink)

Deductivism says that a mathematical sentence s should be understood as expressing the claim that s deductively follows from appropriate axioms. For instance, deductivists might construe “2+2=4” as “the sentence ‘2+2=4’ deductively follows from the axioms of arithmetic”. Deductivism promises a number of benefits. It captures the fairly common idea that mathematics is about “what can be deduced from the axioms”; it avoids an ontology of abstract mathematical objects; and it maintains that our access to mathematical truths requires (...) nothing beyond our ability to make logical deductions. Sections 1 and 2 define and motivate deductivism in more detail. Section 3 covers four authors (Russell, Hilbert, Pasch, Curry) who have endorsed deductivism at some point. Section 4 aims to clarify what semantic claim deductivists make. Sections 5–9 review objections to deductivism and possible replies. (shrink)

"Deductivism" is the thesis that all logic is deductive. Stove lays out the arguments for the existence of non-deductive logic.

In Gemes (1990) I examined certain formal versions of hypothetico-deductivism (H-D) showing that they have the unacceptable consequence that "Abe is a white raven" confirms "All ravens are black"! In Gemes (1992) I developed a new notion of content that could save H-D from this bizarre consequence. In this paper, I argue that more traditional formulations of H-D also need recourse to this new notion of content. I present a new account of the vexing notion of the natural axiomatization (...) of a theory. The notion is used to construct a form of H-D that allows for the type of selective confirmation without which Glymour (1980a,b) claims H-D is hopeless. (shrink)

Since Christensen refuted the Bootstrap theory of confirmation in 1990, there have been some trials to improve the Hypothetico-Deductive theory of confirmation. After some trials, Gemes (1998) declared that his revised version completely overcame the difficulties of Hypothetico-Deductivism without generating any new difficulties. In this paper, I will assert that Gemes's revised version encounters some new difficulties, so it cannot be a true alternative to the Bootstrap theory of confirmation and to classical Hypothetico-Deductivism. Also I will assert that, (...) in principle, such new difficulties cannot be overcome by any trials dependent only on formal logic. (shrink)

: Any precise version of H-D needs to handle various problems, most notably, the problem of selective confirmation: Precise formulations of H-D should not have the consequence that where S confirms T, for any T', S confirms T&T'. It is the perceived failure of H-D to solve such problems that has lead John Earman to recently conclude that H-D is "very nearly a dead horse". This suggests the following state of play: H-D is an intuitively plausible idea that breaks down (...) in the attempt to give it a precise formulation. Indeed I think that fairly captures the view among specialists in the field of confirmation theory. Here I argue that the truth about H-D is largely the reverse: H-D can be given a precise formulation that avoids the longstanding technical problems, however, it relies on a fundamentally unsound philosophical intuition. The bulk of this paper involves reviewing the problems affecting previous attempts at giving precise formulations of H-D and displaying some recent versions that can handle these problems. It then briefly explains why the basic intuition behind H-D is itself unsound, namely, because H-D involves a tacit assumption of inductive scepticism. Finally, the historical relation between H-D and the positivists' quest for a criterion of empirical significance will be reconsidered with the surprising result that having glossed H-D as fundamentally unsound it is concluded that a sound version of the criterion of empirical significance is now available. The demarcation criterion, the positivists' philosopher's stone that serves to separate claims with empirical significance from claims lacking empirical significance having finally been found, it is argued that we should regard empirical significance as just one among a variety of virtues and not follow the positivists in taking it to be a sin qua non for all meaningful statements. (shrink)

The non-justificationist deductivism (or critical rationalism) of Karl Popper constitutes the only approach to human knowledge, including of course the natural and social sciences, that is capable of overcoming all the failings, and the plain contradictions, of the traditional doctrine of inductivism and of its modern incarnation, Bayesianism.

Your use of the JSTOR archive indicates your acceptance of J STOR’s Terms and Conditions of Use, available at http://www.jstor.org/about/terms.html. J STOR’s Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non—commercial use.

Alleged counter-examples deployed in Park [Erkenntnis 60: 229–240] against the account of selective hypothetico-deductive confirmation offered in Gemes [Erkenntnis 49: 1–20] are shown to be ineffective. Furthermore, the reservations expressed in Gemes [ibid] and [Philosophy of Science 62: 477–487] about hypothetico-deductivism are retracted and replaced with the conclusion that H-D is a viable account of confirmation that captures much of the practice of working scientists. However, because it cannot capture cases of inference to the best explanation and cases of (...) the observational confirmation of statistical hypotheses, it is concluded that H-D cannot supply a complete theory of confirmation. (shrink)

It has been a traditional claim that Newtonian inductivism sharply contradicts Cartesian deductivism, and that Newton's rejection of the method of hypothesis is intended as a criticism of the Cartesian scientific methodology. There have been some sharp attacks against the received view that Descartes aimed at the construction of a purely a priori science, but despite this two beliefs still dominate even recent interpretations of Descartes' work. The first is the belief that a significant part of Descartes' natural philosophy (...) was meant to be a priori, and the second is the belief that the Cartesian empirical scientific method was a version of the method of hypothesis. Also, new light has been shed on Newton's famed inductivism and his rejection of the method of hypothesis, a light which shows first, that the traditional inductive interpretation of Newton's method falls significantly short of capturing the richness of this method, and second, that hypotheses play an important role in shaping the conceptual framework in which Newton's work was developed. Despite these recent interpretations, however, an accurate account of Newton's experimental method and an examination of the exact scope and significance of Newton's critique and rejection of the method of hypothesis are still needed. ;The central thesis of this dissertation is that a study of the methodological work and actual scientific practice of Descartes and Newton reveals profound similarities that can be traced back to their employment of the same scientific method of discovery, namely the method of analysis. To that end, I have undertaken a comparative study of the methodological and scientific work of both thinkers. I argue that the official Cartesian method is not the method of hypothesis, and that Descartes did not think any of the parts of his science to be purely a priori. I also argue that the content of Newtonian methodology exceeds that of simple induction, and I try to reconstruct this method as accurately as possible. The conclusion is reached that both Newton and Descartes employed the same scientific method, and that the differences in the fruits delivered by this method are due to the differences between the conceptual frameworks within which Descartes' and Newton's thoughts were developed. (shrink)

The contrast between the two approaches alluded to in the title has gained a certain prominence in our own day. With the knowledge of hindsight it will be of interest therefore to study its incidence in an earlier period, in the writings of Whewell and Mill, Which may thus yield added significance for a later generation. Right at the start there is a difficulty. Not all inductivists agree on their principles, or their interpretation of the logic of scientific reasoning, and (...) the same is true of deductivism, and the differences can therefore be discussed only in connection with individual writers. When this is done, we do find moreover some considerable variations in the treatment of their respective doctrines by the members of each of our two schools. To define these differences, we need a finer structure of elements of classification, indicative of criteria for the acceptance of scientific hypotheses. (shrink)

John Fox argued that deductivism must be supplemented with ‘epistemic syllogisms’, non-deductive arguments whose vindication is trivial if deductivism is correct. I resist this attempt to surpass deductivism.

In “Deductivism as an Interpretative Strategy: A Reply to Groarke’s Defense of Reconstructive Deductivism,” David Godden distinguished two notions of deductivism. On the one hand, as an interpretative thesis, deductivism is the view that all-natural language argumentation must be interpreted as being deductive. On the other hand, as an evaluative thesis, deductivism is the view that for a conclusion to follow, it has to follow of necessity from the premises—or, in other words, that being a (...) good inference implies being deductive. The main goal of this paper is to show that evaluative deductivism is wrong. (shrink)

The aim of this thesis is to understand and critically evaluate deductivism as a theory of inferential sufficiency in informal logic. I distinguish three different types of deductivism: strong normative deductivism, weak normative deductivism, and reconstructive deductivism. I also discuss some potential justificatory strategies that might be invoked in an attempt to justify strong normative deductivism and reconstructive deductivism. I apply this categorization scheme to develop an interpretation of Leo Groarke's version of reconstructive (...) deductivism. I then evaluate some of the criticisms of deductivism raised in the informal logic literature. I focus in particular on the criticisms of Ralph Johnson and Trudy Govier. I follow up this evaluation by raising some problems for the justificatory strategies used to support deductivism. I also show how these problems apply to Groarke's reconstructive deductivism. (shrink)

We use recently developed approaches in argumentation theory in order to revamp the hypothetico-deductive model of confirmation, thus alleviating the well-known paradoxes the H-D account faces. More specifically, we introduce the concept of dialectic confirmation on the background of the so-called theory of dialectical structures (Betz 2010, 2012b). Dialectic confirmation generalises hypothetico-deductive confirmation and mitigates the raven paradox, the grue paradox, the tacking paradox, the paradox from conceptual difference, and the problem of surprising evidence.

There seem to be some very good reasons for a philosopher of science to be a deductivist about scientific reasoning. Deductivism is apparently connected with a demand for clarity and definiteness in the reconstruction of scientists' reasonings. And some philosophers even think that deductivism is the way around the problem of induction. But the deductivist image is challenged by cases of actual scientific reasoning, in which hard-to-state and thus discursively ill-defined elements of thought nonetheless significantly condition what practitioners (...) accept as cogent argument. And arguably, these problem cases abound. For example, even geometry--for most of its history--was such a problem case, despite its exactness and rigor. It took a tremendous effort on the part of Hilbert and others, to make geometry fit the deductivist image. Looking to the empirical sciences, the problems seem worse. Even the most exact and rigorous of empirical sciences--mechanics--is still the kind of problem case which geometry once was. In order for the deductivist image to fit mechanics, Hilbert's sixth problem (for mechanics) would need to be solved. This is a difficult, and perhaps ultimately impossible task, in which the success so far achieved is very limited. I shall explore some consequences of this for realism as well as for deductivism. Through discussing links between non-monotonicity, skills, meaning, globality in cognition, models, scientific understanding, and the ideal of rational unification, I argue that deductivists can defend their image of scientific reasoning only by trivializing it, and that for the adequate illumination of science, insights from anti-deductivism are needed as much as those which come from deductivism. (shrink)

In his paper, "Explanations of Irrelevance" (1983), Paul Horwich proposes an amended version of hypothetico-deductivism, (H-D * ). In this discussion note it is shown that (H-D * ) has the consequence that "A is a non-black raven" confirms "All ravens are black" relative to any tautology! It is noted that Horwich's (H-D * ) bears a strong resemblance to Hempel's prediction criterion of confirmation and that the prediction criterion faces the same obstacle. A related problem for hypothetico-deductivism (...) in its simplest form--that is, E confirms H iff E is an (observational) consequence of H--is displayed. The discussion concludes with a suggestion about how (H-D * ) and simple hypothetico-deductivism might be amended in order to avoid these results. (shrink)

“Deductivism” is a broad label for various theories that emphasize the importance of deductive argument in contexts of rational discussion. This paper makes a case for a very specific form of deductivism. The paper highlights the dialectical importance of advancing deductively valid arguments in natural-language reasoning. Sections 2 and 3 explain the various forms that deductivism has taken. Section 4 makes a case for a particular form of deductivism. Section 5 discusses the value of deductive argument (...) in law. Section 6 concludes and acknowledges critical questions that need to be addressed more fully in future work. (shrink)

Konolige''s technical notion of belief based on deduction structures is briefly reviewed and its usefulness for the design of artificial agents with limited representational and deductive capacities is pointed out. The design of artificial agents with more sophisticated representational and deductive capacities is then taken into account. Extended representational capacities require in the first place a solution to the intensional context problems. As an alternative to Konolige''s modal first-order language, an approach based on type-free property theory is proposed. It considers (...) often neglected issues, such as the need for a more general account of thede dicto-de re distinction, and quasi-indicators. Extended deductive capacities require a subdivision of Konolige''s notion of belief into two distinct technical notions,potential anddispositional belief. The former has to do with what an artificial agent could in principle come to actively believe, given enough time and its specific logical competence; the latter with what an agent can be assumed to believe with respect to a specific goal to be fulfilled. (shrink)

The paper provides a qualified defence of Bruce Waller’s deductivist schema for a priori analogical arguments in ethics and law. One crucial qualification is that the schema represents analogical arguments as complexes composed of one deductive inference but also of one non-deductive subargument. Another important qualification is that the schema is informed by normative assumptions regarding the conditions that an analogical argument must satisfy in order for it to count as an optimal instance of its kind. Waller’s schema is defended (...) from criticisms formulated by Trudy Govier, Marcello Guarini and Lilian Bermejo-Luque. (shrink)

Clark Glymour has argued that hypothetico-deductivism, which many take to be an important method of scientific confirmation, is hopeless because it cannot be reconstructed in classical logic. Such reconstructions, as Glymour points out, fail to uphold the condition of relevance between theory and evidence. I argue that the source of the irrelevant confirmations licensed by these reconstructions lies not with hypothetico-deductivism itself, but with the classical logic in which it is typically reconstructed. I present a new reconstruction of (...) hypothetico-deductivism in relevance logic that does maintain the condition of relevance between theory and evidence. Hence, if hypothetico-deductivism is an important rationale in science, we have good reason to believe that the logic underlying scientific discourse is captured better by relevance logic than by its classical counterpart. (shrink)

Hypothetico-deductivists have struggled to develop qualitative confirmation theories not raising the so-called tacking by disjunction paradox. In this paper, I analyze the difficulties yielded by the paradox and I argue that the hypothetico-deductivist solutions given by Gemes (1998) and Kuipers (2000) are questionable because they do not fit such analysis. I then show that the paradox yields no difficulty for the Bayesian who appeals to the Total Evidence Condition. I finally argue that the same strategy is unavailable to the hypothetico-deductivist.

Poincaré’s conventionalism has been interpreted in many writings as a philosophical position emerged by reflection on certain scientific problems, such as the applicability of geometry to physical space or the status of certain scientific principles. In this paper I would like to consider conventionalism as a philosophical position that emerged from Poincaré’s scientific practice. But not so much from dealing with scientific problems, as from the use of two specific methodologies proper to modern mathematics and the modern natural sciences: methodological (...) structuralism and the hypothetical-deductive method—thus, as a philosophical position which emerged from a way (or rather, two ways) ofdoingscience. With this approach, I try to deepen the analysis of connections between Poincaré’s scientific practice and his philosophy. (shrink)

This paper responds to two aspects of Ralph Johnson's Manifest Rationality (2000). The first is his critique of deductivism. The second is his failure to make room for some species of argument (e.g., visual and kisceral arguments) proposed by recent commentators. In the first case, Johnson holds that argumentation theorists have adopted a notion of argument which is too narrow. In the second, that they have adopted one which is too broad. I discuss the case Johnson makes for both (...) claims, and possible objections to his analysis. (shrink)

a recent paper, Fábio Perin Shecaira proposes a defence of Waller’s deductivist schema for moral analogical argumentation. This defence has several flaws, the most important of them being that many good analogical arguments would be deemed bad or deficient. Additionally, Shecaira misrepresents my alternative account as something in between deductivism and non-deductivism. This paper is both an attempt at solving this misunderstanding and an analysis and criticism of Waller and Shecaira’s forms of deductivism.

Stove argues that Popper and his successors in the philosophy of science, Kuhn, Lakatos and Feyerabend, were irrationalists because they were deductivists. That is, they believed all logic is deductive, and thus denied that experimental evidence could make scientific theories logically more probable. The book was reprinted as Anything Goes (1998) and Scientific Irrationalism: Origins of a Postmodern Cult (1998).

William Whewell tried to explain how scientific knowledge of necessary and certain truth was possible by tracing it to ideas that arose not out of experience but had an independent origin in the mind. Although Whewell has generally been regarded as an a priorist in some sense and as a proponent of hypothetico-deductivism, Snyder tries to show that he can be assimilated to the twentieth-century inductivist mainstream. She fails to make her case, however, in part because she fails to (...) pay sufficient attention to Whewell’s insistence that scientific discovery is beyond the reach of method and always involves happy guesses. (shrink)