In this introductory chapter, I first offer an overview of the two themes addressed in the present collection - namely, disagreement and skepticism - and their connection, then present the purpose and content of the volume.

The question of whether the Pyrrhonist adheres to certain logical principles, criteria of justification, and inference rules is of central importance for the study of Pyrrhonism. Its significance lies in that, whereas the Pyrrhonist describes his philosophical stance and argues against the Dogmatists by means of what may be considered a rational discourse, adherence to any such principles, criteria, and rules does not seem compatible with the radical character of his skepticism. Hence, if the Pyrrhonist does endorse them, one must (...) conclude that he is inconsistent in his outlook. Despite its import, the question under consideration has not received, in the vast literature on Pyrrhonism of the past three decades, all the attention it deserves. In the present paper, I do not propose to provide a full examination of the Pyrrhonist’s attitude towards rationality, but to focus on the question of whether he endorses the law of non-contradiction (LNC). However, I will also briefly tackle the question of the Pyrrhonist’s outlook on both the canons of rational justification at work in the so-called Five Modes of Agrippa and the logical rules of inference. In addition, given that the LNC is deemed a fundamental principle of rationality, determining the Pyrrhonist’s attitude towards it will allow us to understand his general attitude towards rationality. (shrink)

This dissertation is on infinite regress arguments in philosophy. Its main goals are to explain what such arguments from many distinct philosophical debates have in common, and to provide guidelines for using and evaluating them. Two theories are reviewed: the Paradox Theory and the Failure Theory. According to the Paradox Theory, infinite regress arguments can be used to refute an existentially or universally quantified statement (e.g. to refute the statement that at least one discussion is settled, or the statement that (...) discussions are settled only if there is an agreed-upon criterion to settle them). According to the Failure Theory, infinite regress arguments can be used to demonstrate that a certain solution fails to solve an existentially or universally quantified problem (e.g. to demonstrate that a certain solution fails to settle all discussions, or that it fails to settle even one discussion). In the literature, the Paradox Theory is fairly well-developed, and this dissertation provides the Failure Theory with the same tools. (shrink)

In his Pyrrhonian Outlines , Sextus Empiricus employs an argument based upon the possibility of disagreement in order to show that one should not assent to a Dogmatic claim to which at present one cannot oppose a rival claim. The use of this argument seems to be at variance with the Pyrrhonian stance, both because it does not seem to accord with the definition of Skepticism and because the argument appears to entail that the search for truth is doomed to (...) failure. In the present paper, I examine the passages in which Sextus utilizes the argument from possible disagreement and offer an interpretation that makes the use of this argument compatible with the Pyrrhonian outlook. (shrink)

Pyrrhonism was one of the two main ancient skeptical traditions. In this second paper of the three‐part series devoted to ancient skepticism, I present and discuss some of the issues on Pyrrhonian skepticism which have been the focus of much attention in the recent literature. The topics to be addressed concern the outlooks of Pyrrho, Aenesidemus, and Sextus Empiricus.

In this article I examine M. Williams’ antisceptical strategy of considering skepticism as an unnatural position philosophically charged, which for him implies that skepticism has nothing to do with our epistemic practices. I admit that this strategy is really promising, especially when applied to Cartesian scepticism. However, when it faces an older ancestor of Cartesian scepticism, Pyrrhonian scepticism, this situation changes. I concentrate on Fogelin’s neopyrrhonist proposal and how Williams’ strategy would face it. I will defend that Pyrrhonian scepticism is (...) a completely natural kind of scepticism according to our epistemic practices. I will also maintain that this kind of skepticism is the unavoidable result of reflecting about those epistemic practices. (shrink)

Recent literature in epistemology has focused on the following argument for skepticism (SA): I know that I have two hands only if I know that I am not a handless brain in a vat. But I don't know I am not a handless brain in a vat. Therefore, I don't know that I have two hands. Part I of this article reviews two responses to skepticism that emerged in the 1980s and 1990s: sensitivity theories and attributor contextualism. Part II considers (...) the more recent ‘neo-Moorean’ response to skepticism and its development in ‘safety’ theories of knowledge. Part III argues that the skeptical argument set out in SA is not of central importance. Specifically, SA is parasitic on skeptical reasoning that is more powerful and more fundamental than that displayed by SA itself. Finally, Part IV reviews a Pyrrhonian argument for skepticism that is not well captured by SA, and considers a promising strategy for responding to it. (shrink)

In this paper, I examine how the Mode of Infinite Regress functions in Pyrrhonian scepticism. I argue that it is used both to generate an infinite regress of reasons and to show that such infinite regresses are epistemically defective. I clarify precisely how this occurs while examining the Mode’s efficaciousness and whether ancient philosophers might have accepted infinite regresses of reasons. I ultimately argue that they would not for reasons which have hitherto not been adequately appreciated and which shed further (...) light on how the Mode of Infinite Regress functions, its efficacy, and the relevant notions of justification at stake. (shrink)

The Cartesian arguments for external world skepticism are usually considered to be significant for at least two reasons: they seem to present genuine paradoxes and that providing an adequate response to these arguments would reveal something epistemically important about knowledge, justification, and/or our epistemic position to the world. Using only premises and reasoning the skeptic accepts, I will show that the most common Cartesian argument for external world skepticism leads to a previously unrecognized self-undermining dilemma: it either leads to a (...) reductio ad absurdum, or to avoid this reductio the skeptic must accept that this argument is epistemically idle—it does not provide any support for external world skepticism. Either way, this Cartesian argument cannot legitimately threaten or even call into question our beliefs about the external world. And thus, either way, this Cartesian argument for external world skepticism is not epistemically significant—it is not a genuine paradox and adequately responding to it need not reveal anything epistemically important. (shrink)

Is Buddhism’s attitude towards accepted forms of knowledge sceptical? Are Pyrrhonian scepticism and classical Buddhist scholasticism related in their respective applications and expressions of doubt? In what way and to what degree is Critical Buddhism an offshoot of modern scepticism? Questions such as these as well as related issues are explored in the present collection, which brings together examinations of systematic doubt in the traditions of Buddhism from a variety of perspectives. What results from the perceptive observations and profound analytical (...) insights of the seven essays is a rich and multi-faceted picture of two families of philosophical systems—scepticism and Buddhism—that seem both akin and at odds, both related and distant at the same time. (shrink)

The aim of this paper is to show how PH II constitutes an original, ambitious, and unified skeptical inquiry into logic. My thesis is that Sextus’s argument in Book II is meant to accomplish both its stated goal (to investigate the topics typically grouped together by dogmatists under the heading of “logic”) and an unstated goal. The unstated goal is, in my view, interesting in itself and sheds new light on Sextus’s methodology. The goal is: to suspend judgement on the (...) effectiveness of dogmatic methodologies. (shrink)

The five modes are a list of tools used by ancient sceptics to guide dogmatic people towards suspending their judgement. Attributed to Agrippa and used extensively by Sextus Empiricus, these modes are still widely discussed today by epistemologists and specialists in ancient philosophy. Scholars disagree, however, on how to understand the way the five modes are used together and what the logical form of the sceptical strategy behind their deployment is. This paper offers a reconstruction of the system of the (...) five modes that avoids these problems. In specific, unlike previous reconstructions, it includes a non-trivial version of the mode of relativity, avoids committing the sceptic to a normative principle and follows the textual evidence more closely. Moreover, I argue that the system can be better understood as a list of steps in a process, whose underlying logic can be expressed by a single algorithm. (shrink)

Scientific Ontology: Integrating Naturalized Metaphysics and Voluntarist Epistemology, Anjan Chakravartty (2017) New York: Oxford University Press, 296 pp., ISBN 978 0 19065 145 9, h/bk, £53.00.

Though ancient Pyrrhonian skepticism is apparently based on disagreement, this aspect of skepticism has been widely neglected in contemporary discussion on skepticism. The paper provides a rational reconstruction of the skeptical argument from disagreement that can be found in the books of Sextus Empiricus. It is argued that this argument forms a genuine skeptical paradox that has no fully satisfactory resolution. All attempts to resolve it make knowledge or justified belief either intuitively too easy or impossible.

One notable line of argument for epistemic relativism appeals to considerations to do with non-neutrality: in certain dialectical contexts—take for instance the famous dispute between Galileo and Cardinal Bellarmine concerning geocentrism—it seems as though a lack of suitably neutral epistemic standards that either side could appeal to in order to resolve their first-order dispute is itself—as Rorty influentially thought—evidence for epistemic relativism. In this essay, my aim is first to present a more charitable reformulation of this line of reasoning, one (...) that is framed not merely in terms of the availability of epistemic norms that are suitably neutral between interlocutors, but in terms of the availability of what I call Archimedean metanorms. Once this more charitable line of argument is developed, I show how, even though it avoids problems that face ‘non-neutrality’ versions of the argument, it nonetheless runs into various other problems that appear ultimately intractable and, further, that the strategy in question gives us no decisive reason to draw the relativist’s conclusion rather than the Pyrrhonian sceptic’s. (shrink)

Recent research has defended the surprising thesis that in many cases the search for truth is better off if the information exchanged between the members of an epistemic community is limited. This is what one may call the limited information thesis. There is, however, the possibility of an even more radical position than this: the thesis that any communication between peers has zero epistemic value and that the search for truth is better off if the truth-inquirer does not take into (...) consideration the truth-claims of her peers. This can be called the solitude thesis. The paper defends the claim that Descartes is a supporter of the solitude thesis with respect to metaphysical inquiry. The defense is facilitated by means of interpreting textual evidence found in Descartes’ essays Discourse on the Method, The Search for Truth and the Meditations on First Philosophy. (shrink)

An objection that has been raised to the conciliatory stance on the epistemic significance of peer disagreement known as the Equal Weight View is that it is self-defeating, self-undermining, or self-refuting. The proponent of that view claims that equal weight should be given to all the parties to a peer dispute. Hence, if one of his epistemic peers defends the opposite view, he is required to give equal weight to the two rival views, thereby undermining his confidence in the correctness (...) of the Equal Weight View. It seems that the same objection could be leveled against those who claim to suspend judgment in the face of pervasive unresolvable disagreements, as do the Pyrrhonian skeptics. In this paper, I explore the kind of response to the objection that could be offered from a neo-Pyrrhonian perspective, with the aim of better understanding the intriguing character of Pyrrhonian skepticism. (shrink)

This paper argues for the following three claims. First, the Agrippan mode from disagreement does not play a secondary role in inducing suspension of judgment. Second, the Pyrrhonist is not committed to the criteria of justification underlying the Five Modes of Agrippa, which nonetheless does not prevent him from non-doxastically assenting to them. And third, some recent objections to Agrippan Pyrrhonism raised by analytic epistemologists and experimental philosophers fail to appreciate the Pyrrhonist's ad hominem style of argumentation and the real (...) challenge posed by the mode from disagreement. (shrink)

O debate epistemológico ocorrido recentemente sobre o que veio a ser chamado de "o problema do desacordo racional" retomou a discussão, presente no ceticismo antigo, relativa ao significado epistêmico do desacordo. Similar ao cético pirrônico, alguns autores envolvidos no debate contemporâneo argumentaram que em contextos controversos, onde há desacordo sobre alguma questão específica, a atitude racional de ambos os lados do debate é a suspensão do juízo. Para esses autores, tal veredito deve ser estendido a diversas áreas do conhecimento humano, (...) resultando num ceticismo local relativo a tópicos controversos. Este artigo trata dessa problemática no campo científico. Em diversos episódios de controvérsia científica, cientistas exibem desacordos persistentes em que cada lado do debate mantém sua posição em face do desacordo. Nesse contexto, coloca-se a pergunta pela possibilidade do desacordo racional entre cientistas considerados pares epistêmicos. A partir da característica estrutural e dinâmica da ciência, argumenta-se que o desacordo racional entre cientistas é possível. Ou seja, diferente do que sustentam autores contemporâneos, no contexto científico o significado epistêmico do desacordo não é, necessariamente, o agnosticismo. Recent epistemological debate about what came to be called "the problem of rational disagreement" resumed the discussion, present among the ancient skeptics, on the epistemic significance of disagreement. Similar to the Pyrrhonian skeptic, some authors involved in the contemporary debate argued that in controversial contexts, where there is disagreement on some specific matter, the rational attitude of both sides of the debate is the suspension of judgment. For these authors, such a verdict should be extended to several fields of human knowledge, resulting in local skepticism regarding controversial topics. This article addresses this problematic in the scientific field. In several episodes of scientific controversy, scientists exhibit persistent disagreements where each side of the debate maintains his position in the face of disagreement. In this context, the question of the possibility of rational disagreement among scientists considered epistemic peers arises. From the structural and dynamic characteristics of science, it is argued that rational disagreement between scientists is possible. In other words, unlike the claims of contemporary authors, in the scientific context the epistemic significance of disagreement is not, necessarily, agnosticism. (shrink)

En la obra que ahora presentamos al público hispanoparlante, reunimos diez trabajos previamente publicados en lengua italiana que abordan importantes cuestiones que ocupan en este momento a los estudiosos de la filosofía helenística y romana. Sus autores son diez de los más importantes especialistas italianos actuales en el estudio de este periodo histórico.

This paper introduces and defends the paradigm response to external world skepticism. To understand it, consider an analogy. One of the hallmarks of being a bird is an ability to fly. A penguin lacks this hallmark and thus fails to be a paradigm bird. Likewise, there are various hallmarks of knowledge. Some of your external world beliefs lack some of these hallmarks, and thus fail to be paradigm cases of knowledge. Just as the inability of penguins to fly doesn’t prevent (...) them from being birds, likewise the lack of these hallmarks doesn’t prevent your beliefs from being knowledge. It just prevents them from being paradigm cases thereof. (shrink)

Pyrrhonism is the view that we should suspend all our beliefs in order to be rational and reach peace of mind. One of the main objections against this view is that it makes action impossible. One cannot suspend all beliefs and act normally at once. Yet, the question is: What is it about actions that they require beliefs? This issue has hardly been clarified in the literature. This is a bad situation, for if the objection fails and it turns out (...) that the Pyrrhonists found a way to secure peace of mind, we better know the details. In the following, I take up this systematic query and show how the objection can be made precise. Despite Sextus Empiricus? ingenious appearance/reality distinction, which is to ensure Pyrrhonism in this, I eventually argue that a life by appearances is quite unlike a normal life. (shrink)

My objective in this paper is to compare two philosophical problems, the problem of the criterion and the problem of deep disagreement, and note a core similarity which explains why many proposed solutions to these problems seem to fail along similar lines. From this observation, I propose a kind of skeptical solution to the problem of deep disagreement, and this skeptical program has consequences for the problem as it manifests in political epistemology and metaphilosophy.

This book on infinite regress arguments provides (i) an up-to-date overview of the literature on the topic, (ii) ready-to-use insights for all domains of philosophy, and (iii) two case studies to illustrate these insights in some detail. Infinite regress arguments play an important role in all domains of philosophy. There are infinite regresses of reasons, obligations, rules, and disputes, and all are supposed to have their own moral. Yet most of them are involved in controversy. Hence the question is: what (...) exactly is an infinite regress argument, and when is such an argument a good one? (shrink)

It is a common intuition that at least in some cases disagreement has skeptical consequences: the participants are not justified in persisting in their beliefs. I will argue that the currently popular non-dialectical and individualistic accounts of justification, such as evidentialism and reliabilism, cannot explain this intuition and defend the dialectical conception of justification that can explain it. I will also argue that this sort of justification is a necessary condition of knowledge by relying on Craig's genealogy of the concept (...) of knowledge. I will then respond to the accusation that the dialectical conception leads to radical skepticism. My response is partly concessive. It does lead to skepticism in areas where controversy prevails, such as philosophy, politics and religion, but this sort of skepticism is quite intuitive. Finally, I deal with the objection that my defense of skepticism about philosophy is self-refuting. (shrink)

Pyrrhonists provide a way of investigating the world in which conflicting views about a given topic are critically compared, assessed, and juxtaposed. Since Pyrrhonists are ultimately unable to decide between these views, they end up suspending judgment about the issues under examination. In this paper, I consider the question of whether Pyrrhonists can be realists or anti-realists about science, focusing, in particular, on contemporary philosophical discussions about it. Althoughprima faciethe answer seems to be negative, I argue that if realism and (...) anti-realism are understood as philosophical stances rather than particular doctrines—that is, if they are conceptualized in terms of a mode of engagement, a style of reasoning, and some propositional attitudes—the apparent tension between Pyrrhonism, realism, and anti-realism vanishes. The result is a first step in the direction of bringing Pyrrhonism to bear on contemporary debates in the philosophy of science. (shrink)

Se discute el análisis de M. Williams de la Concepción de la Fundamentación Previa de la justificación epistémica –una concepción supuestamente detrás del trilema de Agripa– y se le contrasta con la Concepción del Desafío por Defecto – la concepción alternativa de la justificación epistémica propugnada por Williams. Se argumenta que los privilegios epistémicos predeterminados de la CDD son un eufemismo para estipulaciones epistémicamente arbitrarias, asimismo se argumenta que mientras el CFP puede conducir a paradojas escépticas, la CDD conduce a (...) un pancriticismo paradójico y que cuál de estas dos paradojas preferir es un asunto de gusto o temperamento. Finalmente se arguye que la CDD no es ni una adecuada descripción de nuestra práctica filosófica, ni tampoco de nuestra práctica epistémica cotidiana. Se concluye entonces que la CFP es la concepción superior, aun si pudiese conducir al escepticismo pirrónico. Concluimos argumentando abiertamente en favor de un tipo de dogmatismo no epistémico con implicaciones pirrónicas para las presuposiciones absolutas de la ciencia Estas consecuencias, sin embargo, no tienen por qué ser incompatibles con la investigación científica. (shrink)

Much of present-day epistemology is divided between internalists and externalists. Different as these views are, they have in common that they strip justification from its dialectical component in order to block the skeptic’s argument from disagreement. That is, they allow that one may have justified beliefs even if one is not able to defend it against challenges and resolve the disagreements about them. Lammenranta (2008, 2011a) recently argued that neither internalism nor externalism convinces if we consider the argument in its (...) most interesting format. In this paper I zoom in on this debate, and fix further details of Lammenranta’s lead. Specifically, I will side with skepticism that justification is dialectical, yet only if certain conditions are in place. (shrink)

This article critically reviews a new collection on Pyrrhonism edited by Diego Machuca, Pyrrhonism in Ancient, Modern, and Contemporary Philosophy, which fits within the recent focus on the systematic, philosophical import of Pyrrhonism. In this article I both situate and summarize the problems posed by the authors regarding the Pyrrhonist's position (concerning its coherence, its theoretical motivation, and its practical motivation), and indicate to what extent Pyrrhonists might be able to meet them. I conclude that, so far, Pyrrhonism, i.e. the (...) view which propagates global suspension of belief, remains a promising option. (shrink)

The dissertation examines the nature and epistemic implications of epistemic source circularity. An argument exhibits this type of circularity when at least one of the premises is produced by a belief source the conclusion says is legitimate, e.g. a track record argument for the legitimacy of sense perception that uses premises produced by sense perception. In chapter one I examine this and several other types of circularity, identifying relevant similarities and differences between them. In chapter two I discuss the differences (...) between internalist and externalist analyses of justification. I examine in detail foundationalist and non-foundationalist versions of internalism, and go on to consider how one might characterize externalism: either negatively, by denying particular internalist theses, or positively, in terms of a theory offering different conditions for justification. I discuss the views of reliabilist foundationalists at length. In chapter three I present the internalist objection to externalism that the latter mistakenly permit one to be justified in believing the conclusion of an epistemic source circular inference. I explain the externalists' response that it is not in virtue of their externalism that they permit epistemic source circularity but rather their foundationalism; thus, internalist foundationalists must permit epistemic source circularity as well. I evaluate the positions of several internalists, most of them explicitly foundationalists, and argue that they too cannot avoid permitting epistemic source circularity. In the final chapter I consider whether such circularity is vicious, even though both internalist and externalist foundationalists permit it. I argue that one can sustain an objection to epistemic source circularity by imposing a non-question-begging requirement on justification and explain how respecting this requirement leads one to a non-foundationalist view. I conclude by considering the objection that question-begging leads to a certain arbitrariness in belief formation that should give the foundationalist pause when it comes to determining, at the beginning of inquiry, which beliefs are justified and which are not. The dissertation is primarily concerned with making clear the possible skeptical and non-skeptical positions one can take towards epistemic source circularity. I do not argue for the truth of a particular metaepistemology. (shrink)