Restating an interlocutor’s position in an incredulous tone of voice can sometimes serve legitimate dialectical ends. However, there are cases in which incredulous restatement is out of bounds. This article provides an analysis of one common instance of the inappropriate use of incredulous restatement, which the authors call “modus tonens.” The authors argue that modus tonens is vicious because it pragmatically implicates the view that one’s interlocutor is one’s cognitive subordinate and provides a cue to like-minded (...) onlookers that dialectical opponents are not to be treated as epistemic peers. (shrink)

Despite the widespread popularity of the Creating Shared Value discourse, its ‘business case’ and ‘win–win’ rhetoric remain problematic. This paper adds an inclusive development perspective to the debate, arguing that analysing CSV strategies through an inclusivity lens contributes to a better operationalisation of societal value; makes tensions and contradictions between economic and societal value explicit and uncovers processes of inclusion, exclusion and adverse inclusion. We illustrate this by analysing Nestlé’s CSV strategy in its cocoa supply chains in Ghana based on (...) content analysis of company documents, interviews with value chain actors and stakeholders, and focus groups with farmers. We ask how Nestlé frames and implements its CSV discourse in practice and how this relates to the social, relational and environmental dimensions of inclusive development. Findings show how the company addresses inclusive development dimensions in its corporate discourse, practices and business operations, and what trade-offs it faces. We then unmask the inherent tension between business objectives and societal interests and explain why the scope, issues addressed and societal impacts of CSV remain constrained. We conclude that CSV can help reduce a company’s impact on some persistent societal issues, but that its contribution to transformational change remains limited because the need to uphold competitive advantages and short-term financial performance narrows its ability to address all inclusivity dimensions. Legislation mandating responsible business conduct and due diligence can reduce this inherent tension by levelling the playing field between companies addressing inclusivity issues vis-à-vis those who do not. (shrink)

Das, was gesehen, gehört oder gedacht wird, begreift der Band 23 Manifeste zu Bildakt und Verkörperung nicht als ein passives, sondern aktives Gegenüber. Dieses zeigt sich in Bildern, Objekten, Tönen, Materialien, Wörtern oder Schriftzeichen, welche die Beiträge des Bandes im Sinne einer Kulturtheorie des Entgegenkommenden deuten. Diese gründet auf einer analytischen Herangehensweise, die die Gegenstände der Betrachtung in ihrer Eigenständigkeit respektiert, um den Modus ihrer Aktivität angemessen beschreiben zu können. Die versammelten Untersuchungen aus den Bereichen Kunst- und Bildwissenschaft, Philosophie, (...) Sprachphilosophie sowie Musik- und Filmwissenschaft, nähern sich programmatisch zentralen Begriffen von Active Matter bis zu Verkörperung. (shrink)

Chancy modus ponens is the following inference scheme: ‘probably φ’, ‘if φ, then ψ’, therefore, ‘probably ψ’. I argue that Chancy modus ponens is invalid in general. I further argue that the invalidity of Chancy modus ponens sheds new light on the alleged counterexample to modus ponens presented by McGee. I close by observing that, although Chancy modus ponens is invalid in general, we can recover a restricted sense in which this scheme of inference is (...) valid. (shrink)

The paper is concerned with a logical difficulty which Lionel Shapiro’s deflationist theory of logical consequence (as well as the author’s favoured, non-deflationist theory) gives rise to. It is argued that Shapiro’s non-contractive approach to solving the difficulty, although correct in its broad outlines, is nevertheless extremely problematic in some of its specifics, in particular in its failure to validate certain intuitive rules and laws associated with the principle of modus ponens. An alternative non-contractive theory is offered which does (...) not suffer from the same problem. (shrink)

Studie se zabývá analýzou politické teorie modu vivendi britského politického filosofa Johna Graye, přičemž za její hlavní cíl lze považovat především určení autorovy ideologické pozice v kontextu liberálního myšlení, jakož i posouzení koherence Grayovy teorie s koncepcí liberalismu strachu. Na základě kritické reflexe převažujícího univerzalistického pojetí liberalismu článek identifikuje a analyzuje stěžejní atributy Grayova specifického uchopení liberální teorie v podobě ideálu modu vivendi, etické teorie hodnotového pluralismu, univerzálního minima a hodnoty tolerance. V návaznosti na tuto identifikaci je následně zkoumán i (...) etický rozměr Grayovy politické teorie, jehož charakteristika umožňuje zhodnotit, do jaké míry lze autorovu teorii interpretovat v kontextu liberálního myšlení. V této souvislosti se studie rovněž snaží ukotvit Grayovu tvorbu v širším rámci alternativních projektů liberální teorie, když usiluje o prokázání principiálních paralel mezi Grayovým politickým modelem a politickým myšlením Bernarda Williamse jakožto stěžejním představitelem tzv. liberalismu strachu. Výzkum těchto paralel pak přispívá především k nastolení otázek souvisejících s možností důsledného odlišování politické a morální teorie a chápání konfliktu jakožto neodmyslitelné součásti politické reality v rámci současného liberalismu. The paper aims to analyse the political theory of modus vivendi by political philosopher John Gray and to determine the ideological standpoints of Gray's theory within the context of liberal thought as well as to assess its coherence with the concept of liberalism of fear. On the basis of a critical reflection of the prevailing universalistic conception of liberalism, the study identifies and analyses essential attributes of Gray's specific but controversial political theory: the ideal of modus vivendi; ethical theory of value pluralism; universal minimum and the value of toleration. Having interpreted all those main parts of the concept, the study is supposed to clarify also the ethical dimension of Gray's theory which makes it possible to decide to what extent the author might be identified as a liberal thinker. In this regard, the study endeavours to embed Gray's thought in a broader framework of alternative projects of liberal theory by demonstrating fundamental parallels between Gray's model and political thought of Bernard Williams as the main theoretician of liberalism of fear. Investigations of those parallels thus contributes towards articulating questions concerning the possibility of consistently distinguishing between the political and the moral theory as well as perception of a conflict as an ineradicable part of political reality in the framework of contemporary liberalism. (shrink)

If modus ponens is valid, then you should take up smoking.

A central task in contemporary political philosophy is to identify principles governing political life where citizens disagree deeply on important questions of value and, more generally, about the proper ends of life. The distinctively liberal response to this challenge insists that the state should as far as possible avoid relying on such contested issues in its basic structure and deliberations. David McCabe critically surveys influential defenses of the liberal solution and advocates modus vivendi liberalism as an alternative defense of (...) the liberal state. Acknowledging that the modus vivendi approach does not provide the deep moral consensus that many liberals demand, he defends the liberal state as an acceptable compromise among citizens who will continue to see it as less than ideal. His book will interest a wide range of readers in political philosophy and political theory. (shrink)

Is modus ponens valid for the indicative conditional? McGee [1985] famously presents several alleged counterexamples to this inference rule. More recently, Kolodny and MacFarlane [2010] and Willer [2010] argue that modus ponens is unreliable in certain hypothetical contexts. However, none of these attacks undermines an informational conception of logic on which modus ponens is valid.

A polity is grounded in a modus vivendi (MV) when its main features can be presented as the outcome of a virtually unrestricted bargaining process. Is MV compatible with the consensus-based account of liberal legitimacy, i.e. the view that political authority is well grounded only if the citizenry have in some sense freely consented to its exercise? I show that the attraction of MV for consensus theorists lies mainly in the thought that a MV can be presented as legitimated (...) through a realist account of public justification. Yet I argue that, because of persistent ethical diversity, that realism problematically conflicts with the liberal commitments that underpin the very ideas of consensus and public justification. Thus, despite the interest it has recently attracted from critics of political liberalism and deliberative democracy, MV is not an option for those wishing to ground liberal political authority in some form of consensus. So if realist and agonistic critiques are on target, then the fact that modus vivendi is not an option casts some serious doubt on the viability of the consensus view of liberal legitimacy. (shrink)

There is a renewed debate about modus ponens. Strikingly, the recent counterexamples in Cantwell, Dreier and MacFarlane and Kolodny are generated by restricted readings of the ‘if’-clause. Moreover, it can be argued on general grounds that the restrictor view of conditionals developed in Kratzer and Lewis leads to counterexamples to modus ponens. This paper provides a careful analysis of modus ponens within the framework of the restrictor view. Despite appearances to the contrary, there is a robust sense (...) in which modus ponens is valid, owing to the fact that conditionals do not only allow for restricted readings but have bare interpretations, too. (shrink)

This essay examines the promise of the notion of modus vivendi for realist political theory. I interpret recent theories of modus vivendi as affirming the priority of peace over justice, and explore several ways of making sense of this idea. I proceed to identify two key problems for modus vivendi theory, so conceived. Normatively speaking, it remains unclear how this approach can sustain a realist critique of Rawlsian theorizing about justice while avoiding a Hobbesian endorsement of absolutism. (...) And conceptually, the theory remains wedded to a key feature of social contract theory: political order is conceived as based on agreement. This construes the horizontal tensions among individual or group agents in society as prior to the vertical, authoritative relations between authorities and their subjects. Political authority thereby appears from the start as a solution to societal conflict, rather than a problem in itself. I argue that this way of framing the issue abstracts from political experience. Instead I attempt to rethink the notion of modus vivendi from within the lived experience of political conflict, as oriented not primarily toward peace, but political survival. With this shift of perspective, the idea of modus vivendi shows us, pace Bernard Williams, that the “first political question” is not how to achieve order and stability, but rather: what can I live with? (shrink)

In the recent paper “Naive modus ponens”, Zardini presents some brief considerations against an approach to semantic paradoxes that rejects the transitivity of entailment. The problem with the approach is, according to Zardini, that the failure of a meta-inference closely resembling modus ponens clashes both with the logical idea of modus ponens as a valid inference and the semantic idea of the conditional as requiring that a true conditional cannot have true antecedent and false consequent. I respond (...) on behalf of the non-transitive approach. I argue that the meta-inference in question is independent from the logical idea of modus ponens, and that the semantic idea of the conditional as formulated by Zardini is inadequate for his purposes because it is spelled out in a vocabulary not suitable for evaluating the adequacy of the conditional in semantics for non-transitive entailment. I proceed to generalize the semantic idea of the conditional and show that the most popular semantics for non-transitive entailment satisfies the new formulation. (shrink)

This paper defends a counterexample to Modus Tollens, and uses it to draw some conclusions about the logic and semantics of indicative conditionals and probability operators in natural language. Along the way we investigate some of the interactions of these expressions with 'knows', and we call into question the thesis that all knowledge ascriptions have truth-conditions.

This article deals with modus vivendi, toleration and power. On the face of it toleration and modus vivendi are in tension with each other, because of the power condition on toleration: that an agent is tolerant only if they have the power to engage in an alternative, non- or intolerant form of behaviour, and this seems to be absent in modus vivendi. The article argues that the scope of the power condition is unclear, but might be thought (...) much more extensive than usually supposed. This becomes clear when the agent’s thoughts are subjected to a counterfactual test, concerning what would occur in their ideal world. However it is in the nature of ideals that they cannot usually be subject to a counterfactual variation here, since they determine the ideal world’s content. The article concludes that only a commitment to the other party’s freedom for its own sake proves robust in the face of counterfactual idealisation, but that it is questionable whether the dispositions that characterise toleration should be subject to so demanding a test. (shrink)

Modus Darwin is a principle of inference that licenses the conclusion that two species have a common ancestor, based on the observation that they are similar. The present paper investigates the principle's probabilistic foundations.

McGee argued that modus ponens was invalid for the natural language conditional ‘If…then…’. Many subsequent responses have argued that, while McGee’s examples show that modus ponens fails to preserve truth, they do not show that modus ponens fails to preserve rational full acceptance, and thus modus ponens may still be valid in the latter informational sense. I show that when we turn our attention from indicative conditionals to subjunctive conditionals, we find that modus ponens does (...) not preserve either truth or rational full acceptance, and thus is not valid in either sense. In concluding I briefly consider how we can account for these facts. (shrink)

Contemporary political theory is characterised by a realistic critique of liberalism. Realist theorising is seen as avoiding foundational disagreements about justice mutating into second-order disputes concerning the justifiability of legitimate political institutions. In this sense, the realist critique challenges a key aspect of Rawls’ liberal project – that is, its justificatory constituency. McCabe’s Modus Vivendi Liberalism presents an interesting case of such a critique. Given the condition of deep pluralism that characterizes contemporary democracies, the liberal Justificatory Requirement (JR) should (...) be recast so to include those, illiberal or sceptical, who are excluded by Rawls’ justificatory constituency. This paper confronts McCabe’s modus vivendi justificatory project with Rawls view. It suggests that both views seem to endorse a practice-dependent account of political justice in which “politics is prior to morality”; yet the ways in which reasons are endorsed to justify the shared conception of political authority are significantly different in these two schemes. The paper shows that the most problematic aspect of McCabe contingent model is that it disconnects the idea of legitimacy from a conception of liberal political morality. On this account, political legitimacy that reflects the uncoercive character of extant institutions seems to be sufficient to meet the MVL JR. Yet, from a normative point of view, this might be not enough to ensure morally acceptable outcomes. In conclusion, the paper considers McCabe’s model as a version of ‘practice-independent’ moral theorizing committed to a transcendent view of ‘threshold morality’. This move, however, comes at the cost of sacrificing the theory’s premises of anti-perfectionism and realism. (shrink)

We establish a probabilized version of modus tollens, deriving from p(E|H)=a and p()=b the best possible bounds on p(). In particular, we show that p() 1 as a, b 1, and also as a, b 0. Introduction Probabilities of conditionals Conditional probabilities 3.1 Adams' thesis 3.2 Modus ponens for conditional probabilities 3.3 Modus tollens for conditional probabilities.

ABSTRACT ‘Modus Darwin’ is the name given by Elliott Sober to a form of argument that he attributes to Darwin in the Origin of Species, and to subsequent evolutionary biologists who have reasoned in the same way. In short, the argument form goes: similarity, ergo common ancestry. In this article, I review and critique Sober’s analysis of Darwin’s reasoning. I argue that modus Darwin has serious limitations that make the argument form unsuitable for supporting Darwin’s conclusions, and that (...) Darwin did not reason in this way. (shrink)

This chapter assesses John Gray’s modus vivendi-based justification for liberalism. I argue that his approach is preferable to the more orthodox deontological or teleological justificatory strategies, at least because of the way it can deal with the problem of diversity. But then I show how that is not good news for liberalism, for grounding liberal political authority in a modus vivendi undermines liberalism’s aspiration to occupy a privileged normative position vis-à-vis other kinds of regimes. So modus vivendi (...) can save liberalism from moralism, but at cost many liberals will not be prepared to pay. (shrink)

After some motivating remarks in Section 1, in Section 2 we show how to replace an axiomatic basis for any one of a broad range of sentential logics having finitely many axiom schemes and Modus Ponens as the sole proper rule, by a basis with the same axiom schemes and finitely many one-premiss rules. Section 3 mentions some questions arising from this replacement procedure , explores another such procedure, and discusses some aspects of the consequence relations associated with the (...) different axiomatizations in play. Several open problems are mentioned. An appendix briefly treats the issue of a similar ‘at most one-premiss rules’ reformulation of proof systems with sequent-to-sequent rules. (shrink)

In this paper I seek to explore how the idea of modus vivendi might help us to understand political legitimacy. A suitable conception of modus vivendi, I suggest, can represent a way of underpinning a viable and attractive account of political legitimacy. On my account a modus vivendi is basically a set of arrangements that are accepted as basis for conducting affairs by those who are party to them. Political legitimacy, I argue, is ultimately rooted in the (...) judgements of those subject to it, but is mediated through a language in which claims to it are argued and assessed. The thought is that the web of operative beliefs and values in any given society, which constitute the grounds of judgements about political legitimacy, are what sustains a modus vivendi around the basic political institutions and practices. On this view, legitimate political institutions and practices incline towards a modus vivendi in that they are the outcome of an historical and ongoing conglomeration of settlements reflecting shifting and conflicting values and interests, as well relative balances of power, both currently and in the past. The marriage of modus vivendi and political legitimacy, therefore, seeks to reflect the contingent and ‘negotiated’ character of basic political institutions and practices and an understanding of political legitimacy that sees it as mediated through an ongoing and emergent discourse of argument and judgement, which remains nonetheless always vulnerable to challenge and change. (shrink)

In recent years a number of political theorists, dissatisfied with what they see as a dominant but wrongheaded approach to political philosophy exemplified in what they call “liberal moralism,” have endorsed a modus vivendi approach as a framework for evaluating political institutions around the globe. In this paper I discuss this approach in the face of a serious challenge that can be raised against it. The challenge is to show that as an approach to global political morality modus (...) vivendi is both essentially different from the liberal moralism it rejects and normatively and conceptually compelling as a way of answering fundamental questions of political morality. To satisfy the first, global modus vivendi must avoid appealing to the parochial notions of universal norms, human nature, and human interests that are often said to mar liberal moralism. To satisfy the second, it must posit some universal moral standards of minimally decent treatment. In this chapter I pursue these challenges to determine whether modus vivendi is best seen as a genuine alternative to liberal moralism or instead simply as a more chastened and sensible version of that approach. (shrink)

The article discusses a methodological position that allows interpreting modes and, fist of all, musical modes as cosmographic and ethical objects without losing the approach to them as musical phenomena proper. The study is based on musical theoretical data relating to the period of Classical antiquity and the Middle Ages, as well as on the author's concept of modal ontology and the interpretation of modus as artistic content, developed by E.V. Nazaikinsky. In order to reveal the ontological prerequisites for (...) the unity of the musical modus with a cosmographic or ethical phenomenon, the author analyzes the ancient Chinese system of tones lü, Indian ragas, ancient tetrachords, the voices of the Russian Orthodox znamenny chant. The features of the correspondence of these musical phenomena to the periods of the year or day, elements, archetypal states of the human spirit, social laws are revealed. In the course of the analysis, the question is formulated about the nature of the connection between musical modes and non-musical reality: was it exclusively conventional, established by virtue of tradition, or did it have other, essential reasons? The search for unconventional foundations of the unity of musical modes with natural and socio-ethical phenomena leads to its ontological interpretation. The relevance of this research method is argued in the process of critical analysis of the semiotic approach to musical modes as references or conventional signs of objects. It also demonstrates the unproductiveness of the psychoemotional interpretation of musical modes as stimuli that cause certain emotional states. The result of the research is the development of a specific musical-ontological approach based on the methodology of modal analysis. This analysis aims at a syncretic understanding of unity. In the light of this approach, it was concluded that the concept of musical modus not only clarifies the rhythmic and harmonic laws of the musical language, but also embodies the interconnection of the phenomena of music, human spirit, nature, and space. (shrink)

So far, the value dimension underlying affectivity disorders has remained out of focus in phenomenological psychopathology. As early as at the beginning of the 20th century, however, German phenomenologist Max Scheler examined in depth the relationship between affectivity and value dimension through the concept of valueception (Wertnehmung). In this sense, a recent noteworthy contribution has been provided by John Cutting, who has drawn attention to the importance of Scheler’s analyses for psychiatry. In this work I take into consideration only two (...) aspects of Cutting’s proposal: 1) the relationship between the impairments of valueception and the perception of certain value classes; and 2) the interpretation of Scheler’s phenomenological reduction and its juxtaposition with the modus vivendi of schizophrenia. According to Cutting, in the modus vivendi of schizophrenia the valueception impairment entails putting vital values in brackets and focusing on personal values, with a process that recalls Scheler’s phenomenological reduction. Regarding the first aspect, I share Cutting’s starting point, but then shift the focus on how important the valueception is for the intersubjective dimension. In particular, I maintain that rather than compromising the perception of vital values, valueception impairments in the modus vivendi of schizophrenia interfere with the intersubjective dimension and are interwoven with a process of disembodiment. My thesis is that the modus vivendi of schizophrenia involves a disturbance of the intersubjective dimension that arises from the level of valueception and that determines the person’s self-referential closure. With regard to the second point, by analyzing Scheler’s phenomenological reduction, I sustain that its main objective is to increase both the interaction with otherness and the openness to the world (Weltoffenheit). As a consequence, the modus vivendi of schizophrenia, in my opinion, is not comparable, as Cutting claims, with Scheler’s phenomenological reduction, but goes in a different direction. (shrink)

Considering the instability of nonlinear dynamics, the deductive inference rule Modus ponens itself is not enough to guarantee the validity of reasoning sequences in the real physical world, and similar results cannot necessarily be obtained from similar causes. Some kind of stability hypothesis should be added in order to draw meaningful conclusions. Hence, the uncertainty of deductive inference appears to be like that of inductive inference, and the asymmetry between deduction and induction becomes unrecognizable such as to undermine the (...) basis for the fundamental cleavage between analytic truth and synthetic truth, as W. V. O. Quine pointed out. Induction is not inferior to deduction from a pragmatic point of view. (shrink)

Este artigo tem como objetivo compreender a institucionalização e o funcionamento do Conselho de Alimentação Escolar enquanto um conselho gestor de política pública no município de Ijuí, localizado no Noroeste do Estado do Rio Grande do Sul, bem como analisar sua atuação e os desafios da gestão. O referencial teórico utilizado foi de conselhos gestores de políticas públicas na perspectiva da gestão social. Trata-se de uma pesquisa exploratória, cuja estratégia de investigação foi o estudo de caso único, com abordagem qualitativa (...) dos dados coletados por meio de pesquisa documental e entrevistas. Os resultados apontam a atuação do CAE em Ijuí/RS como efetiva, apesar dos entraves enfrentados. O principal desafio identificado foi quanto à recomposição de seus membros, processo que está ocorrendo com êxito. Conclui-se que a institucionalização de um CAE ocorre a partir da interação entre os diferentes órgãos que compõem um programa governamental, como no caso do PNAE, e que o seu funcionamento depende da atuação efetiva de todos os atores envolvidos. (shrink)

In this chapter, I address the two closely related notions of modus vivendi and toleration. Drawing from conceptual clarifications and a distinction between different conceptions of toleration, I argue that an analogous discussion can be provided for the concept of modus vivendi and for a distinction between different conceptions of it. The resulting conceptions of modus vivendi, and especially a distinct ethical conception, allow for a more precise and more promising line of argument when it comes to (...) using the notion of modus vivendi in current debates in political philosophy. (shrink)

The first colleges of the Society of Jesus, since the foundation of the one at Messina in 1548, chose to follow the notably participative pedagogy of the University of Paris. The article shows why and how the option for the modus parisiensis was made. The University of Paris, which the first companions knew through having studied there, had an academic structure more centred on the professor's authority than at the other European universities. This, however, did not prevent numerous contacts (...) between the students and the teaching body, with each group having its precise rules. Parisian teaching was progressive and systematic, very open to the culture of the Renaissance, and to ancient languages and authors. The influence of the «Brothers of the Common Life» is clear, especially regards their attention to the human and spiritual formation of the students. (shrink)

"Theory of modus concipiendi in Richard Burthogge’s Epistemology" The paper focuses on the epistemology of Richard Burthogge, the lesser known seventeenth-century English philosopher and author, among other works, of the Organum Vetus & Novum (1678) and An Essay upon Reason and the Nature of Spirits (1694). Although his ideas had a minimal impact on the philosophy of his time, and have hitherto not been the subject of a detailed study, Burthogge’s writings contain a highly original concept of idealistic constructivism. (...) The most important claim of this approach is that the external objects are never presented to the mind directly, as they are in themselves, but always under the modus concipiendi, a particular form of conceiving or conceptualising, performed by the human cognitive powers (both intellectual and sensuous) in the manner and with the means determined by their structural and functional properties. Thus, Burthogge clearly anticipates Kant in claiming that the external world is unknowable in itself, being accessible to the human mind only through the phenomena that the mind itself co-produces. The paper provides an outline of the theory of modus concipiendi, including its historical context and idealistic consequences, preceded by the brief presentation of Burthogge’s epistemology. (shrink)

When we enquire into political legitimacy, we are, broadly speaking, exploring the question of whether a particular ruler or regime rules rightfully. We are interested in whether the rule is characterised by right or is merely a form of rule via coercion, a distinction that is usually put in terms of de jure and de facto order. While this question is basic to political experience, there nevertheless might be different ways in which it can be formulated which in turn will (...) influence what is going to count as an adequate answer. In this chapter I want to express some concerns as to the way in which much contemporary modus vivendi theories have either raised the question of political legitimacy or the sort of answer that it takes to be sufficient. That is to say, it has either tended to get the question wrong or the answer, or both. In the end, I want to suggest that modus vivendi can only represent a coherent and distinct political theory if it takes its Hobbesian heritage seriously and accept that the provision of order is both a necessary and a sufficient condition of legitimacy. Whether that is an attractive way of thinking about politics is a different question. (shrink)

ABSTRACT: This paper traces the earliest development of the most basic principle of deduction, i.e. modus ponens (or Law of Detachment). ‘Aristotelian logic’, as it was taught from late antiquity until the 20th century, commonly included a short presentation of the argument forms modus (ponendo) ponens, modus (tollendo) tollens, modus ponendo tollens, and modus tollendo ponens. In late antiquity, arguments of these forms were generally classified as ‘hypothetical syllogisms’. However, Aristotle did not discuss such arguments, (...) nor did he call any arguments ‘hypothetical syllogisms’. The Stoic indemonstrables resemble the modus ponens/tollens arguments. But the Stoics never called them ‘hypothetical syllogisms’; nor did they describe them as ponendo ponens, etc. The tradition of the four argument forms and the classification of the arguments as hypothetical syllogisms hence need some explaining. In this paper, I offer some explanations by tracing the development of certain elements of Aristotle’s logic via the early Peripatetics to the logic of later antiquity. I consider the questions: How did the four argument forms arise? Why were there four of them? Why were arguments of these forms called ‘hypothetical syllogisms’? On what grounds were they considered valid? I argue that such arguments were neither part of Aristotle’s dialectic, nor simply the result of an adoption of elements of Stoic logic, but the outcome of a long, gradual development that begins with Aristotle’s logic as preserved in his Topics and Prior Analytics; and that, as a result, we have a Peripatetic logic of hypothetical inferences which is a far cry both from Stoic logic and from classical propositional logic, but which sports a number of interesting characteristics, some of which bear a cunning resemblance to some 20th century theories. (shrink)

There are narrowest bounds for P(h) when P(e) = y and P(h/e) = x, which bounds collapse to x as y goes to 1. A theorem for these bounds -- bounds for probable modus ponens -- entails a principle for updating on possibly uncertain evidence subject to these bounds that is a generalization of the principle for updating by conditioning on certain evidence. This way of updating on possibly uncertain evidence is appropriate when updating by ’probability kinematics’ or ’Jeffrey-conditioning’ (...) is, and apparently in countless other cases as well. A more complicated theorem due to Karl Wagner -- bounds for probable modus tollens -- registers narrowest bounds for P(not h) when P(not e) = y and P(e/h) = x. This theorem serves another principle for updating on possibly uncertain evidence that might be termed ’contraditioning’, though it is for a way of updating that seems in practice to be frequently not appropriate. It is definitely not a way of putting down a theory -- for example, a random-chanc. (shrink)

While John Rawls made the notion of a “modus vivendi” prominent in political philosophy, he treats modus vivendi arrangements rather short and dismissively. On the other hand, some political theorists like John Gray praise modus vivendi as the only available and legitimate goal of politics. In the article I sketch the outlines of a different, more nuanced approach to modus vivendi arrangements. I argue that the moral standing of modus vivendi arrangements varies, and I try (...) to spell out the factors that determine the relative moral standing of modus vivendi arrangements. (shrink)

The precedent studies on the validity of Modus ponens and Modus tollens have been carried out with most regard to a major type of conditionals in which the conditional clause is a sufficient condition for the main clause. But we sometimes, in natural language arguments, find other types of conditionals in which the conditional clause is a necessary or necessary and sufficient condition for the main clause. In this paper I reappraise, on the basis of new definitions of (...) Modus ponens and Modus tollens, their validity/invalidity in natural language arguments in consideration of all types of conditionals. (shrink)

Modus Darwin is the name given by Elliott Sober to a form of argument that Sober attributes to Darwin in the Origin of Species, and to subsequent evolutionary biologists who have reasoned in the same way. In short, the argument form goes: Similarity, ergo common ancestry. In the present paper I review and critique Sober's analysis of Darwin's reasoning. I argue that modus Darwin has serious limitations that make the argument form unsuited for supporting Darwin's conclusions, and that (...) Darwin did not reason in this way. (shrink)

This article concerns the structure of defeasible arguments like: 'If Bob has red spots, Bob has the measles; Bob has red spots; therefore Bob has the measles.' The issue is whether such arguments have the form of modus ponens or not. Either way there is a problem. If they don't have the form of modus ponens, the common opinion to the contrary taught in leading logic textbooks is wrong. But if they do have the form of modus (...) ponens, doubts are raised about the conventional dogma that all arguments having the form of modus ponens are deductively valid. By carefully examining arguments on both sides of the issue, reasonable doubts are raised about the view that all arguments having a modus ponens form are valid. (shrink)

Medical diagnosis has been traditionally recognized as a privileged field of application for so called probabilistic induction. Consequently, the Bayesian theorem, which mathematically formalizes this form of inference, has been seen as the most adequate tool for quantifying the uncertainty surrounding the diagnosis by providing probabilities of different diagnostic hypotheses, given symptomatic or laboratory data. On the other side, it has also been remarked that differential diagnosis rather works by exclusion, e.g. by modus tollens, i.e. deductively. By drawing on (...) a case history, this paper aims at clarifying some points on the issue. Namely: 1) Medical diagnosis does not represent, strictly speaking, a form of induction, but a type, of what in Peircean terms should be called ‘abduction’ (identifying a case as the token of a specific type); 2) in performing the single diagnostic steps, however, different inferential methods are used for both inductive and deductive nature: modus tollens, hypothetical-deductive method, abduction; 3) Bayes’ theorem is a probabilized form of abduction which uses mathematics in order to justify the degree of confidence which can be entertained on a hypothesis given the available evidence; 4) although theoretically irreconcilable, in practice, both the hypothetical- deductive method and the Bayesian one, are used in the same diagnosis with no serious compromise for its correctness; 5) Medical diagnosis, especially differential diagnosis, also uses a kind of “probabilistic modus tollens”, in that, signs (symptoms or laboratory data) are taken as strong evidence for a given hypothesis not to be true: the focus is not on hypothesis confirmation, but instead on its refutation [Pr (¬ H/E1, E2, …, En)]. Especially at the beginning of a complicated case, odds are between the hypothesis that is potentially being excluded and a vague “other”. This procedure has the advantage of providing a clue of what evidence to look for and to eventually reduce the set of candidate hypotheses if conclusive negative evidence is found. 6) Bayes’ theorem in the hypothesis-confirmation form can more faithfully, although idealistically, represent the medical diagnosis when the diagnostic itinerary has come to a reduced set of plausible hypotheses after a process of progressive elimination of candidate hypotheses; 7) Bayes’ theorem is however indispensable in the case of litigation in order to assess doctor’s responsibility for medical error by taking into account the weight of the evidence at his disposal. (shrink)

In Summa theologiae, Ia, 75.5, Aquinas writes, "It is evident that all that is received in anything is received in it according to the mode of the receiver." Aquinas employs this principle throughout his career and across the full range of philosophical topics. Beginning with Quaestianes de veritate 2.5, he employs a more universal formulation which he applies even to divine being: "All that is in anything is in it according to the mode of that in which it is." As (...) modus is the term common to the principle's two formulations, I call it the modus principle. ;The dissertation is a comprehensive study of Thomas's use of the principle, based on computer research done with the Index Thomisticus and the St. Thomas CD-ROM. The 200 texts located are considered according to applications in the order of knowing, the order of being, and the order of predicating. In brief, Aquinas employs the modus principle and the term modus to give account of the intelligible coenactment in knowledge of the knower and the known; to give account of the entitative contrariety evident among beings; and to frame an analogy of being based on a primacy of existence. The principal conclusions drawn from the textual survey are that the modus principle belongs among the most basic axioms of Thomas's metaphysics, that it pertains directly to the metaphysical ultimate of his thought, namely esse, and that at the heart of the principle is a concept central to his metaphysics, namely modes of existence. ;When Aquinas subordinates formal contrariety to an actuality more ultimate than form, namely existence, a new concept of existential distinction emerges. Modus is a term of entitative contrariety that becomes necessary when a real duality of essence and existence is seen as necessary to all finite being. As Thomas traces this entitative composition to a participation in ipsum esse commune, and ultimately to a participation in ipsum esse per se subsistens, the term modus and the modus principle are seen to be in the service of his creationist metaphysics. (shrink)

The compositional structure of language might have led one to expect that a proper analysis of simple conditionals would have been adequate to determine the analysis of iterated conditionals. But McGee has presented an interesting group of examples that shows that this is not so for indicative conditionals. The examples are particularly arresting since they appear to show that modus ponens does not hold as a generally valid rule of inference for conditionals in natural language.

In a recent pair of publications, Richard Bradley has offered two novel no-go theorems involving the principle of Preservation for conditionals, which guarantees that one’s prior conditional beliefs will exhibit a certain degree of inertia in the face of a change in one’s non-conditional beliefs. We first note that Bradley’s original discussions of these results—in which he finds motivation for rejecting Preservation, first in a principle of Commutativity, then in a doxastic analogue of the rule of modus ponens —are (...) problematic in a significant number of respects. We then turn to a recent U-turn on his part, in which he winds up rescinding his commitment to modus ponens, on the grounds of a tension with the rule of Import-Export for conditionals. Here we offer an important positive contribution to the literature, settling the following crucial question that Bradley leaves unanswered: assuming that one gives up on full-blown modus ponens on the grounds of its incompatibility with Import-Export, what weakened version of the principle should one be settling for instead? Our discussion of the issue turns out to unearth an interesting connection between epistemic undermining and the apparent failures of modus ponens in McGee’s famous counterexamples. (shrink)

Modus ponens (from A and “if A then C” infer C) is one of the most basic inference rules. The probabilistic modus ponens allows for managing uncertainty by transmitting assigned uncertainties from the premises to the conclusion (i.e., from P(A) and P(C|A) infer P(C)). In this paper, we generalize the probabilistic modus ponens by replacing A by the conditional event A|H. The resulting inference rule involves iterated conditionals (formalized by conditional random quantities) and propagates previsions from the (...) premises to the conclusion. Interestingly, the propagation rules for the lower and the upper bounds on the conclusion of the generalized probabilistic modus ponens coincide with the respective bounds on the conclusion for the (non-nested) probabilistic modus ponens. (shrink)

Recently, there has been a shift away from traditional truth-conditional accounts of meaning towards non-truth-conditional ones, e.g., expressivism, relativism and certain forms of dynamic semantics. Fueling this trend is some puzzling behavior of modal discourse. One particularly surprising manifestation of such behavior is the alleged failure of some of the most entrenched classical rules of inference; viz., modus ponens and modus tollens. These revisionary, non-truth-conditional accounts tout these failures, and the alleged tension between the behavior of modal vocabulary (...) and classical logic, as data in support of their departure from tradition, since the revisionary semantics invalidate some of these patterns. I, instead, offer a semantics for modality with the resources to accommodate the puzzling data while preserving classical logic, thus affirming the tradition that modals express ordinary truth-conditional content. My account shows that the real lesson of the apparent counterexamples is not the one the critics draw, but rather one they missed: namely, that there are linguistic mechanisms, reflected in the logical form, that affect the interpretation of modal language in a context in a systematic and precise way, which have to be captured by any adequate semantic account of the interaction between discourse context and modal vocabulary. The semantic theory I develop specifies these mechanisms and captures precisely how they affect the interpretation of modals in a context, and do so in a way that both explains the appearance of the putative counterexamples and preserves classical logic. (shrink)