Kearns and Star have previously recommended that we measure the degree to which a reason supports a conclusion, either about how to act or what to believe, as the conditional probability of the conclusion given the reason. I show how to properly formulate this recommendation to allow for dependencies and conditional dependencies among the considerations being aggregated. This formulation allows us to account for how considerations, which do not themselves favour a specific conclusion, can modify the strength of a reason (...) for that conclusion, and thus to explain the intensifiers and attenuators described by Dancy. The formulation also accounts for the workings of partial undercutters in epistemology. I then show how my account avoids the counterexamples that Brunero levied against probability-based theories of the strengths of reasons. My account supports the theory, suggested by Kearns and Star, that the strengths of reasons are measured by conditional probabilities. If my account is successful, then it will count in favour of the idea that the strengths of reasons are measured on the same scale as are conditional probabilities. (shrink)

This chapter explores global debunking arguments, debunking arguments that aim to give one a global defeater. I defend Alvin Plantinga’s view that global defeaters are possible and, once gained, are impossible to escape by reasoning. They thereby must be extinguished by other means: epistemically propitious actions, luck, or grace. I then distinguish between three types of global defeater—pure-undercutters, undercutters-because-rebutters, and undercutters-while-rebutters—and systematically consider how one can deflect such defeaters. Lastly, since I draw insights from the literature on perhaps the most (...) widely discussed global debunking argument in the literature, Plantinga’s evolutionary argument against naturalism, I end up responding to many potential problems for it. This includes the so-called conditionalization problem, as well as those raised by Bergmann (2002), Law (2012), Deem (2018), Hendricks and Anderson (2020), and Wielenberg (in Craig and Wielenberg (2021)). (shrink)

The Toulmin diagram layout is very familiar and widely used, particularly in the teaching of critical thinking skills. The conventional box-and-arrow diagram is equally familiar and widespread. Translation between the two throws up a number of interesting challenges. Some of these challenges (such as the relationship between Toulmin warrants and their counterparts in traditional diagrams) represent slightly different ways of looking at old and deep theoretical questions. Others (such as how to allow Toulmin diagrams to be recursive) are diagrammatic versions (...) of questions that have already been addressed in artificial intelligence models of argument. But there are further questions (such as the relationships between refutations, rebuttals and undercutters, and the roles of multiple warrants) that are posed as a specific result of examining the diagram inter-translation problem. These three classes of problems are discussed. To the first class are addressed solutions based on engineering pragmatism; to the second class, are addressed solutions drawn from the appropriate literature; and to the third class, fuller exploration is offered justifying the approaches taken in developing solutions that offer both pragmatic utility and theoretical interest. Finally, these solutions are explored briefly in the context of the Araucaria system, showing the ways in which analysts can tackle arguments either using one diagrammatic style or another, or even a combination of the two. (shrink)

Two notions from philosophical logic and linguistics are brought together and applied to the psychological study of defeasible conditional reasoning. The distinction between disabling conditions and alternative causes is shown to be a special case of Pollock’s (1987) distinction between ‘rebutting’ and ‘undercutting’ defeaters. ‘Inferential’ conditionals are shown to come in two varieties, one that is sensitive to rebutters, the other to undercutters. It is thus predicted and demonstrated in two experiments that the type of inferential conditional used as the (...) major premise of conditional arguments can reverse the heretofore classic, distinctive effects of defeaters. (shrink)

Why are personal attacks so powerful? In political debates, speeches, discussions and campaigns, negative character judgments, aggressive charges and charged epithets are used for different purposes. They can block the dialogue, trigger value judgments and influence decisions; they can force the interlocutor to withdraw a viewpoint or undermine his arguments. Personal attacks are not only multifaceted dialogical moves, but also complex argumentative strategies. They can be considered as premises for further arguments based on signs, generalizations or consequences. They involve tactics (...) for arousing emotions such as fear, hate or contempt, or for ridiculing the interlocutor. The twofold level of investigation presented in this paper is aimed at distinguishing the different roles that ad hominem have in a dialogue and bringing to light their hidden dimensions. The reasoning structure of each type of attack will be distinguished from the tactics used to increase its effectiveness and conceal its weaknesses. (shrink)

Two notions from philosophical logic and linguistics are brought together and applied to the psychological study of defeasible conditional reasoning. The distinction between disabling conditions and alternative causes is shown to be a special case of Pollock's (1987) distinction between ‘rebutting' and ‘undercutting' defeaters. ‘Inferential' conditionals are shown to come in two types, one that is sensitive to rebutters, the other to undercutters. It is thus predicted and demonstrated in two experiments that the type of inferential conditional used as the (...) major premise of conditional arguments can reverse the heretofore classic, distinctive effects of defeaters. (shrink)

Stephen Toulmin once observed that ”it has never been customary for philosophers to pay much attention to the rhetoric of mathematical debate’ [Toulmin et al., 1979, An Introduction to Reasoning, Macmillan, London, p. 89]. Might the application of Toulmin’s layout of arguments to mathematics remedy this oversight? Toulmin’s critics fault the layout as requiring so much abstraction as to permit incompatible reconstructions. Mathematical proofs may indeed be represented by fundamentally distinct layouts. However, cases of genuine conflict characteristically reflect an underlying (...) disagreement about the nature of the proof in question. (shrink)

Two notions from philosophical logic and linguistics are brought together and applied to the psychological study of defeasible conditional reasoning. The distinction between disabling conditions and alternative causes is shown to be a special case of Pollock’s (1987) distinction between ‘rebutting’ and ‘undercutting’ defeaters. ‘Inferential’ conditionals are shown to come in two varieties, one that is sensitive to rebutters, the other to undercutters. It is thus predicted and demonstrated in two experiments that the type of inferential conditional used as the (...) major premise of conditional arguments can reverse the heretofore classic, distinctive effects of defeaters. (shrink)

Two notions from philosophical logic and linguistics are brought together and applied to the psychological study of defeasible conditional reasoning. The distinction between disabling conditions and alternative causes is shown to be a special case of Pollock’s (1987) distinction between ‘rebutting’ and ‘undercutting’ defeaters. ‘Inferential’ conditionals are shown to come in two varieties, one that is sensitive to rebutters, the other to undercutters. It is thus predicted and demonstrated in two experiments that the type of inferential conditional used as the (...) major premise of conditional arguments can reverse the heretofore classic, distinctive effects of defeaters. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Review of Stephen Phillips' Jewel of Reflection on the Truth about Epistemology:A Complete and Annotated Translation of the Tattva-cintā-maṇiMichael Williams (bio)Stephen Phillips presents a translation and commentary on Gaṅgeśa Upādhyāya's Tattvacintāmaṇi, which is widely regarded as the foundational text of the Navya-Nyāya tradition. The importance of Gaṅgeśa's work to subsequent philosophy in India can hardly be overstated. In the centuries after his death, countless commentaries and dissertations were written (...) on the Tattvacintāmaṇi by Nyāya scholars in Mithila and Bengal. Recent [End Page 510] scholarship (David and Duquette 2021) has highlighted how the work of the Navya-Naiyāyikas came to influence intellectuals from all over the Indian subcontinent. The theories of Gaṅgeśa and his followers shaped discussions in diverse scientific fields, including Vedānta, Mīmāṃsā, grammatical science, and literary theory.Despite its pervasive impact on Indian thought, Navya-Nyāya has frequently been portrayed in a negative light by scholars. The Indologist Arthur Berriedale Keith (1921, p. 35) described the commentaries on Gaṅgeśa's work as "a vast mass of perverted ingenuity worthy of the most flourishing days of mediaeval scholasticism." Meanwhile, Swami Vivekananda bemoaned the "never ending Avacchinnas and Avacchedakas" of Navya-Nyāya prose.1Jonardon Ganeri (2011) has discussed how these negative stereotypes reach back to the political agenda of the British colonial government in India during the nineteenth century, and his work highlights the vitality and diversity of the discussion of metaphysics in the Bengali tradition of Navya-Nyāya. Nevertheless, there is no denying that much Navya-Nyāya work is extremely difficult to discuss and translate comprehensibly. Many scholars still think of Navya-Nyāya works as untranslatable, at least in the sense that their meaning could not be effectively communicated to a modern audience who are not already deeply familiar with the tradition. This would be tragic, given the potential of Navya-Nyāya philosophy to contribute to the growing cross-cultural conversation in philosophy.Phillips is the first scholar to translate the entire Tattvacintāmaṇi into another language. His work attempts to communicate the foundational text of the Navya-Nyāya tradition to a broad audience. In his introduction, Phillips says that his work aims to speak to analytic philosophers, Sanskritists, and "specialists whose interests span issues in contemporary philosophy and Gaṅgeśa's achievements" (2020, vol. 1, p. 1). Phillips worked with the late Ramanuja Tatacharya to read the Tattvacintāmaṇi's chapters on perception and inference. Tatacharya was recognized as one of the leading experts on Navya-Nyāya philosophy in the world during his lifetime, and Phillips' translation distils many of his insights into the text.Phillips' goal is to translate the Tattvacintāmaṇi into lucid English. He eschews what he terms the "error of literalism" (2020, 1:xvi), instead using idiomatic translations that draw on concepts from contemporary analytic philosophy. Unlike Daniel Ingalls (1951) and Cornelius Goekoop (1967), Phillips uses formalization in Property Predicate Logic comparatively rarely, deploying it selectively in contexts such as the discussion of the nature of pervasion (the Vyāptivāda) and the discussion of the "inferential undercutter" (the Upādhivāda), for instance. The introduction to the work is extremely clear and explains the translation using terms of modern analytic philosophy. Phillips presents a perspicuous introduction to the theory of inference, [End Page 511] which is necessary to understanding Gaṅgeśa's work, which constantly employs inferential arguments.Phillips' introductions to the individual chapters of the text are also very illuminating, and often contain original insights into the philosophy of the Tattvacintāmaṇi. For instance, his introduction to the Īśvaravāda argues, contra John Vattanky ([1989] 2011), that Gaṅgeśa himself was not entirely persuaded of the strength of the proofs for the existence of god (īśvara) that he puts forward in that chapter. Phillips argues that Gaṅgeśa may actually have sympathized to some extent with the Mīmāṃsā views he ultimately critiques there, detecting on Gaṅgeśa's part a "sympathy for certain atheistic... (shrink)