I present a case for a rapprochement between aspects of rationalism and scientific realism, by way of a general framework employing modal epistemology and elements of 2-dimensional semantics (2DS). My overall argument strategy is meta-inductive: The bulk of this paper establishes a “base case,” i.e., a concretely constructive example by which I demonstrate this linkage. The base case or constructive example acts as the exemplar for generating, in a constructively ‘bottom-up’ fashion, a more generally rigorous case for (...) class='Hi'>rationalism-realism qua modal epistemology. The exemple I choose in D. Chalmers’ (2002) modal rationalism and R. Giere’s (1985, 1988) constructive realism. I show by way of a thorough analysis how Giere’s claims concerning modal scope are characterized as instances of Chalmers’ modal rationalism, both weak and strong. In essence, as I demonstrate via Chalmers’ notions, ceteris paribus the constructive realist ultimately opts for a comparatively wider gate, characterized by modal reasoning, to lead from the rooms of conceivability qua thought experiments and models, to the pastures of metaphysical possibility. Chalmers likewise tries to erect such a wider gate, in his general conceivability-possibility theses. Anti-realists, on the other hand, see a narrower passage and my contention herein is that they suffer from modal myopia, which hopefully the ‘corrective vision’ of Chalmers’ modal rationalism can restore. In the introduction and concluding sections I sketch out suggestions of constructing ‘inductive steps’ from my base case, to generate more extensively general claims regarding realism qua rationalism. -/- . (shrink)

In this paper, we argue that ‘Weak Modal Rationalism’, which is the view that ideal primary positive conceivability entails primary metaphysical possibility, is self-defeating. To this end, we outline two reductio arguments against ‘Weak Modal Rationalism’. The first reductio shows that, from supposing that ‘Weak Modal Rationalism’ is true, it follows that conceivability both is and is not conclusive evidence for possibility. The second reductio shows that, from supposing that ‘Weak (...) Modal Rationalism’ is true, it follows that it is possible that ‘Weak Modal Rationalism’ is necessarily false, and hence that ‘Weak Modal Rationalism’ is false. We then argue that adopting a weaker position according to which conceivability is merely prima facie evidence for possibility provides limited protection from our criticism of conceivability arguments. (shrink)

It used to be thought that rational coherence and metaphysical possibility went hand in hand. Kripke and Putnam put a spanner in the works by proposing examples of propositions which seem to violate this principle. I will propose a nuanced form of modal rationalism consistent with the Kripke/putnam cases. The rough idea is that rational coherence entails possibility when you grasp the essential nature of what you’re conceiving of.

The objection from the insolvability of principle-based modal disagreements appears to support the claim that there are no objective modal facts, or at the very least modal facts cannot be accounted for by modal rationalist theories. An idea that resurfaced fairly recently in the literature is that the use of ordinary empirical statements presupposes some prior grasp of modal notions. If this is correct, then the idea that we may have a total agreement concerning empirical (...) facts and disagree on modal facts, which is the starting point of the objection from the insolvability of modal disagreement, is undercut. This paper examines the no-separation thesis and shows that some of the arguments against the classical (empiricist) distinction between empirical and modal statements fail to be conclusive if they are taken to defend a strong notion of metaphysical possibility. The no-separation thesis appears to work only in theoretical frameworks where metaphysical modalities are considered (broadly) conceptual. For these reasons, the no-separation thesis cannot save modal rationalism from the insolvability of modal disagreement. (shrink)

In this chapter, it is suggested that our epistemic access to metaphysical modality generally involves rationalist, a priori elements. However, these a priori elements are much more subtle than ‘traditional’ modal rationalism assumes. In fact, some might even question the ‘apriority’ of these elements, but I should stress that I consider a priori and a posteriori elements especially in our modal inquiry to be so deeply intertwined that it is not easy to tell them apart. Supposed metaphysically (...) necessary identity statements involving natural kind terms are a good example: the fact that empirical input is crucial in establishing their necessity has clouded the role and content of the a priori input, as I have previously argued. For instance, the supposed metaphysically necessary identity statement involving water and its microstructure can only be established with the help of a controversial a priori principle concerning the determination of chemical properties by microstructure. The Kripke-Putnam framework of modal epistemology fails precisely because it is unclear whether the required a priori element is present. My positive proposal builds on E. J. Lowe’s work. Lowe holds that our knowledge of metaphysical modality is based on our knowledge of essence. Lowe’s account strives to offer a uniform picture of modal epistemology: essence is the basis of all our modal knowledge. This is the basis of Lowe’s modal rationalism. I believe that Lowe’s proposal is on the right lines in the case of abstract objects, but I doubt that it can be successfully applied to the case of natural kinds. Accordingly, the case of natural kinds will be my main focus and I will suggest that modal rationalism, at least as it is traditionally understood, falls short of explaining modal knowledge concerning natural kinds. Yet, I think that Lowe has identified something of crucial importance for modal epistemology, namely the essentialist, a priori elements present in our modal inquiry. The upshot is that rather than moving all the way from modal rationalism to modal empiricism, a type of hybrid approach, ‘empirically-informed modal rationalism ’, can be developed. (shrink)

In this paper, I discuss the main characteristics of the epistemology of modal rationalism by proceeding from the critical investigation of Peacocke’s theory of modality. I build on arguments by Crispin Wright and Sonia Roca-Royes, which are generalised and supplemented by further analysis, in order to show that principle-based accounts have little prospects of succeeding in their task of providing an integrated account of the metaphysics and the epistemology of modality. I argue that it is unlikely that we (...) will able to develop an exhaustive and accurate principle-based account that discriminates objectively between correct and deviant modal knowledge. Even if such an account can be formulated, a non-circular way of justifying its necessity also seems to be out of our reach. (shrink)

A consequence relation is strongly classical if it has all the theorems and entailments of classical logic as well as the usual meta-rules (such as Conditional Proof). A consequence relation is weakly classical if it has all the theorems and entailments of classical logic but lacks the usual meta-rules. The most familiar example of a weakly classical consequence relation comes from a simple supervaluational approach to modelling vague language. This approach is formally equivalent to an account of logical consequence according (...) to which α1, ..., αn entails β just in case □α1, ..., □αn entails □β in the modal logic S5. This raises a natural question: If we start with a different underlying modal logic, can we generate a strongly classical logic? This paper explores this question. In particular, it discusses four related technical issues: (1) Which base modal logics generate strongly classical logics and which generate weakly classical logics? (2) Which base logics generate themselves? (3) How can we directly characterize the logic generated from a given base logic? (4) Given a logic that can be generated, which base logics generate it? The answers to these questions have philosophical interest. They can help us to determine whether there is a plausible supervaluational approach to modelling vague language that yields the usual meta-rules. They can also help us to determine the feasibility of other philosophical projects that rely on an analogous formalism, such as the project of defining logical consequence in terms of the preservation of an epistemic status. (shrink)

The paper begins with a clarification of the notions of intuition (and, in particular, modal intuition), modal error, conceivability, metaphysical possibility, and epistemic possibility. It is argued that two-dimensionalism is the wrong framework for modal epistemology and that a certain nonreductionist approach to the theory of concepts and propositions is required instead. Finally, there is an examination of moderate rationalism’s impact on modal arguments in the philosophy of mind -- for example, Yablo’s disembodiment argument and (...) Chalmers’s zombie argument. A less vulnerable style of modal argument is defended, which nevertheless wins the same anti-materialist conclusions sought by these other arguments. (shrink)

This dissertation contains four independent essays addressing a cluster of related topics in the philosophy of mind. Chapter 1: “Fundamentality Physicalism” argues that physicalism can usefully be conceived of as a thesis about fundamentality. The chapter explores a variety of other potential formulations of physicalism (particularly modal formulations), contrasts fundamentality physicalism with these theses, and offers reasons to prefer fundamentality physicalism over these rivals. Chapter 2:“Modal Rationalism and the Demonstrative Reply to the Master Argument Against Physicalism” introduces (...) the Master Argument Against Physicalism and investigates its crucial premise: the inference from an a priori gap between the physical and consciousness to a lack of necessitation between the two. I argue against the strong form of modal rationalism that underwrites the master argument and offer a more moderate rationalist view. I offer a novel demonstrative reply to the master argument, according to which a connection between conscious experience and demonstratives, not dualism, is the source of the epistemic gap between consciousness and the physical. Chapter 3: “Conceptual Mastery and the Knowledge Argument” argues that Frank Jackson’s famous anti-physicalist knowledge argument featuring Mary, a brilliant neuroscientist raised in a black and white room, founders on a dilemma. Either (i) Mary cannot know the relevant experiential truths because of trivial obstacles that have no bearing on the truth of physicalism or (ii) once the obstacles have been removed, Mary can know the relevant truths. Chapter 4: “Toward a Theory of Conceptual Mastery” investigates the question “Under what conditions does a thinker fully understand, or have mastery of, a concept?” I argue against three views of conceptual mastery, according to which conceptual mastery is a matter of holding certain beliefs, being disposed to make certain inferences, or having certain intuitions. I propose and respond to objections to my own “meaning postulate view” of the conditions under which a thinker has mastery of a concept. (shrink)

This paper develops an account of the meaning of `ought', and the distinction between weak necessity modals (`ought', `should') and strong necessity modals (`must', `have to'). I argue that there is nothing specially ``strong'' about strong necessity modals per se: uses of `Must p' predicate the (deontic/epistemic/etc.) necessity of the prejacent p of the actual world (evaluation world). The apparent ``weakness'' of weak necessity modals derives from their bracketing whether the necessity of the prejacent is verified in the (...) actual world. `Ought p' can be accepted without needing to settle that the relevant considerations (norms, expectations, etc.) that actually apply verify the necessity of p. I call the basic account a modal-past approach to the weak/strong necessity modal distinction (for reasons that become evident). Several ways of implementing the approach in the formal semantics/pragmatics are critically examined. The account systematizes a wide range of linguistic phenomena: it generalizes across flavors of modality; it elucidates a special role that weak necessity modals play in discourse and planning; it captures contrasting logical, expressive, and illocutionary properties of weak and strong necessity modals; and it sheds light on how a notion of `ought' is often expressed in other languages. These phenomena have resisted systematic explanation. In closing I briefly consider how linguistic inquiry into differences among necessity modals may improve theorizing on broader philosophical issues. (shrink)

The article argues against attempts to combine ontological realism about modality with the rejection of modal rationalism and it suggests that modal realism requires modal rationalism. /// El artículo da argumentos en contra de que se intente combinar el realismo ontológico sobre la modalidad con el rechazo del racionalismo modal y sugiere que el realismo modal exige racionalismo modal.

Weakly Aggregative Modal Logic (WAML) is a collection of disguised polyadic modal logics with n-ary modalities whose arguments are all the same. WAML has some interesting applications on epistemic logic and logic of games, so we study some basic model theoretical aspects of WAML in this paper. Specifically, we give a van Benthem-Rosen characterization theorem of WAML based on an intuitive notion of bisimulation and show that each basic WAML system Kn lacks Craig Interpolation.

We defend the view of epistemic `must' as weak and claim that `must p' is used when the speaker does not know p. Novel arguments for this well-known account are provided. The theory is extended to epistemic future.

Metaphysical rationalism, the doctrine which affirms the Principle of Sufficient Reason (the PSR), is out of favor today. The best argument against it is that it appears to lead to necessitarianism, the claim that all truths are necessarily true. Whatever the intuitive appeal of the PSR, the intuitive appeal of the claim that things could have been otherwise is greater. This problem did not go unnoticed by the great metaphysical rationalists Spinoza and Leibniz. Spinoza’s response was to embrace necessitarianism. (...) Leibniz’s response was to argue that, despite appearances, rationalism does not lead to necessitarianism. This paper examines the debate between these two rationalists and concludes that Leibniz has persuasive grounds for his opinion. This has significant implications both for the plausibility of the PSR and for our understanding of modality. (shrink)

This article proposes a way of blocking the zombie argument against materialism. The central idea—which can be motivated in various ways, but which I will motivate by drawing on recent work by Wolfgang Schwarz—is that sentences reporting conscious experience are modally inert, roughly in the sense that adding them to a description of a metaphysically possible scenario always results in a description of a metaphysically possible scenario. This is notable in that it leads to a way of blocking the zombie (...) argument, which is perfectly compatible with modal rationalism and with the view that conceivability entails possibility. (shrink)

The paper explores the project of an ambitious modal epistemology that attempts to combine the a priori methods of Chalmers’ 2D semantics with Kripke’s modal metaphysics. I argue that such a project is not viable. The ambitious modal epistemology involves an inconsistent triad composed of (1) Modal Monism, (2) Two-Dimensionalism, and what I call (3) “Metaphysical Kripkeanism”. I present the three theses and show how only two of those can be true at a time. There is (...) a fundamental incompatibility between Chalmers’ Modal Rationalism and Kripke’s modal metaphysics. Specifically, Chalmers’ conceivability entails possibilities that a Kripkean rejects as genuinely metaphysical. However, three positive stances in modal epistemology emerge from the combinations that the triad allows. One of those offers a promising way forward for 2D modal epistemologies. But it comes with a cost, as it requires abandoning modal monism and reshaping the scope of what a priori conceivability can give us access to. (shrink)

We present an inferentialist account of the epistemic modal operator might. Our starting point is the bilateralist programme. A bilateralist explains the operator not in terms of the speech act of rejection ; we explain the operator might in terms of weak assertion, a speech act whose existence we argue for on the basis of linguistic evidence. We show that our account of might provides a solution to certain well-known puzzles about the semantics of modal vocabulary whilst (...) retaining classical logic. This demonstrates that an inferentialist approach to meaning can be successfully extended beyond the core logical constants. (shrink)

Modal rationalists uphold a strong constitutive relationship between a priori cognition and modal cognition. Since both a priori cognition and modal cognition have been taken to be characteristic of philosophical insights, I will critically assess an ambitious modal rationalism and an associated ambitious methodological rationalism. I begin by examining Kripkean cases of the necessary a posteriori in order to characterize the ambitious modal rationalism that will be the focus of my criticism. I (...) then argue that there is a principled association between this view in the epistemology of modality and an ambitious methodological rationalist picture of the nature of philosophical insights. On the basis of this discussion, I criticize ambitious modal rationalism and argue that the critique indicates some principled limits of generating philosophical insights by a priori modal cognition. Hence, my central diagnosis is that ambitious methodological rationalists are overly ambitious in the role that they assign a priori modal cognition in philosophical methodology. -/-. (shrink)

Recent work on the imagination has stressed the epistemic significance of imaginative experiences, notably in justifying modal beliefs. An immediate problem with this is that modal beliefs appear to admit of justification through the mere exercise of rational capacities. For instance, mastery of the concepts of square, circle, and possibility should suffice to form the justified belief that a square circle is not possible, and mastery of the concepts of pig, flying, and possibility should suffice to form a (...) justified belief that a flying pig is possible. It is thus unnecessary to try to imagine a square circle or a flying pig to justify these beliefs. In this paper, I consider three ways to defend the epistemic role of imagination in modal epistemology against this challenge. One claims that modal beliefs simply admit of justification by two separate sources: rational capacities and imaginative experience. Another holds that while beliefs about logical or conceptual modality can be justified entirely by rational capacities, beliefs about metaphysical modality require imaginative experiences. The third, which I defend, is the idea that imagination is relevant in the first instance not to modal knowledge but to modal understanding: even where imaginative experience is unnecessary for the justification of modal beliefs, it is indispensable for directly grasping certain modal propositions. (shrink)

Though the study of grounding is still in the early stages, Kit Fine, in ”The Pure Logic of Ground”, has made a seminal attempt at formalization. Formalization of this sort is supposed to bring clarity and precision to our theorizing, as it has to the study of other metaphysically important phenomena, like modality and vagueness. Unfortunately, as I will argue, Fine ties the formal treatment of grounding to the obscure notion of a weak ground. The obscurity of weak (...) ground, together with its centrality in Fine’s system, threatens to undermine the extent to which this formalization offers clarity and precision. In this paper, I show how to overcome this problem. I describe a system, the logic of strict ground (LSG) and demonstrate its adequacy; I specify a translation scheme for interpreting Fine’s weak grounding claims; I show that the interpretation verifies all of the principles of Fine’s system; and I show that derivability in Fine’s system can be exactly characterized in terms of derivability in LSG. I conclude that Fine’s system is reducible to LSG. (shrink)

This collection highlights the new trend away from rationalism and toward empiricism in the epistemology of modality. Accordingly, the book represents a wide range of positions on the empirical sources of modal knowledge. Readers will find an introduction that surveys the field and provides a brief overview of the work, which progresses from empirically-sensitive rationalist accounts to fully empiricist accounts of modal knowledge. Early chapters focus on challenges to rationalist theories, essence-based approaches to modal knowledge, and (...) the prospects for naturalizing modal epistemology. The middle chapters present positive accounts that reject rationalism, but which stop short of advocating exclusive appeal to empirical sources of modal knowledge. The final chapters mark a transition toward exclusive reliance on empirical sources of modal knowledge. They explore ways of making similarity-based, analogical, inductive, and abductive arguments for modal claims based on empirical information. Modal epistemology is coming into its own as a field, and this book has the potential to anchor a new research agenda. (shrink)

The paper argues against Peacocke's moderate rationalism in modality. In the first part, I show, by identifying an argumentative gap in its epistemology, that Peacocke's account has not met the Integration Challenge. I then argue that we should modify the account's metaphysics of modal concepts in order to avoid implausible consequences with regards to their possession conditions. This modification generates no extra explanatory gap. Yet, once the minimal modification that avoids those implausible consequences is made, the resulting account (...) cannot support Peacocke's moderate rationalism. (shrink)

ABSTRACTLinguistic evidence supports the claim that certain, weak rejections are less specific than assertions. On the basis of this evidence, it has been argued that rejected sentences cannot be premisses and conclusions in inferences. We give examples of inferences with weakly rejected sentences as premisses and conclusions. We then propose a logic of weak rejection which accounts for the relevant phenomena and is motivated by principles of coherence in dialogue. We give a semantics for which this logic is (...) sound and complete, show that it axiomatizes the modal logic KD45 and prove that it still derives classical logic on its asserted fragment. Finally, we defend previous logics of strong rejection as being about the linguistically preferred interpretations of weak rejections. (shrink)

This paper is about three of the most prominent debates in modern epistemology. The conclusion is that three prima facie appealing positions in these debates cannot be held simultaneously. The first debate is scepticism vs anti-scepticism. My conclusions apply to most kinds of debates between sceptics and their opponents, but I will focus on the inductive sceptic, who claims we cannot come to know what will happen in the future by induction. This is a fairly weak kind of scepticism, (...) and I suspect many philosophers who are generally anti-sceptical are attracted by this kind of scepticism. Still, even this kind of scepticism is quite unintuitive. I’m pretty sure I know (1) on the basis of induction. (1) It will snow in Ithaca next winter. Although I am taking a very strong version of anti-scepticism to be intuitively true here, the points I make will generalise to most other versions of scepticism. (Focussing on the inductive sceptic avoids some potential complications that I will note as they arise.) The second debate is a version of rationalism vs empiricism. The kind of rationalist I have in mind accepts that some deeply contingent propositions can be known a priori, and the empiricist I have in mind denies this. Kripke showed that there are contingent propositions that can be known a priori. One example is Water is the watery stuff of our acquaintance. (‘Watery’ is David Chalmers’s nice term for the properties of water by which folk identify it.) All the examples Kripke gave are of propositions that are, to use Gareth Evans’s term, deeply necessary (Evans, 1979). It is a matter of controversy presently just how to analyse Evans’s concepts of deep necessity and contingency, but most of the controversies are over details that are not important right here. I’ll simply adopt Stephen Yablo’s recent suggestion: a proposition is deeply contingent if it could have turned out to be true, and could have turned out to be false (Yablo, 2002)1. Kripke did not provide examples of any deeply contingent propositions knowable a priori, though nothing he showed rules out their existence.. (shrink)

The philosophy of necessity and possibility has flourished in the last half-century, but much less attention has been paid to the question of how we know what can be the case and what must be the case. Many friends of modal metaphysics and many enemies of modal metaphysics have agreed that while empirical discoveries can tell us what is the case, they cannot shed much light on what must be the case or on what non-actual possibilities there are. (...) In this paper, in contrast, I discuss and defend naturalistic approaches to discovering the facts about necessity and possibility. After some remarks about what methodological naturalism in philosophy might amount to, I argue that naturalistic method in modal investigations may not need to be particularly revisionary of much of what is currently being done in modal investigation. I then discuss a number of respects in which a naturalistic orientation in modal investigation may improve on our current epistemic situation. (shrink)

Dugundji proved in 1940 that most parts of standard modal systems cannot be characterized by a single finite deterministic matrix. In the eighties, Ivlev proposed a semantics of four-valued non-deterministic matrices (which he called quasi-matrices), in order to characterize a hierarchy of weak modal logics without the necessitation rule. In a previous paper, we extended some systems of Ivlev’s hierarchy, also proposing weaker six-valued systems in which the (T) axiom was replaced by the deontic (D) axiom. In (...) this paper, we propose even weaker systems, by eliminating both axioms, which are characterized by eight-valued non-deterministic matrices. In addition, we prove completeness for those new systems. It is natural to ask if a characterization by finite ordinary (deterministic) logical matrices would be possible for all those Ivlev-like systems. We will show that finite deterministic matrices do not characterize any of them. (shrink)

My goal in this paper is to show that Kant’s prohibition on certain kinds of knowledge of things-in-themselves is motivated less by his anti-soporific encounter with Hume than by his new view of the distinction between “real” and “logical” modality, a view that developed out of his reflection on the rationalist tradition in which he was trained. In brief: at some point in the 1770’s, Kant came to hold that a necessary condition on knowing a proposition is that one be (...) able to prove that all the items it refers to are either really possible or really impossible. Most propositions about things-in-themselves, in turns out, cannot meet this condition. I conclude by suggesting that the best interpretation of this modal condition is as a kind of coherentist constraint. (shrink)

Recent research on algebraic models of _quasi-Nelson logic_ has brought new attention to a number of classes of algebras which result from enriching (subreducts of) Heyting algebras with a special modal operator, known in the literature as a _nucleus_. Among these various algebraic structures, for which we employ the umbrella term _intuitionistic modal algebras_, some have been studied since at least the 1970s, usually within the framework of topology and sheaf theory. Others may seem more exotic, for their (...) primitive operations arise from algebraic terms of the intuitionistic modal language which have not been previously considered. We shall for instance investigate the variety of _weak implicative semilattices_, whose members are (non-necessarily distributive) meet semilattices endowed with a nucleus and an implication operation which is not a relative pseudo-complement but satisfies the postulates of Celani and Jansana’s strict implication. For each of these new classes of algebras we establish a representation and a topological duality which generalize the known ones for Heyting algebras enriched with a nucleus. (shrink)

Some central epistemological notions are expressed by sentential operators O that entail the possibility of knowledge in the sense that 'Op' entails 'It is possible to know that p'. We call these modal-epistemological notions. Using apriority and being in a position to know as case studies, we argue that the logics of modal epistemological notions are extremely weak. In particular, their logics are not normal and do not include any closure principles.

According to principles of modal security, evidence undermines a belief only when it calls into question certain purportedly important modal connections between one’s beliefs and the truth (e.g., safety or sensitivity). Justin Clarke-Doane and Dan Baras have advanced such principles with the aim of blocking evolutionary moral debunking arguments. We examine a variety of different principles of modal security, showing that some of these are too strong, failing to accommodate clear cases of undermining, while others are too (...) weak, failing to do their advertised work of blocking evolutionary moral debunking arguments. If there is a security principle that slips between the horns of this dilemma—one that is both viable and debunker-blocking—it remains to be formulated. (shrink)

A prevailing thought is that generics have a covert modal operator at logical form. I claim that if this is right, the covert generic modality is a weak necessity modal. In this paper, I pr...

My topic is moderate modal skepticism in the spirit of Peter van Inwagen. Here understood, this is a conservative version of modal empiricism that severely limits the extent to which an ordinary agent can reasonably believe “exotic” possibility claims. I offer a novel argument in support of this brand of skepticism: modal skepticism grounds an attractive (and novel) reply to Humean skepticism. Thus, I propose that modal skepticism be accepted on the basis of its theoretical utility (...) as a tool for dissolving philosophical paradox. (shrink)

Actualists of a certain stripe—dispositionalists—hold that metaphysical modality is grounded in the powers of actual things. Roughly: p is possible iff something has, or some things have, the power to bring it about that p. Extant critiques of dispositionalism focus on its material adequacy, and question whether there are enough powers to account for all the possibilities we intuitively want to countenance. For instance, it seems possible that none of the actual contingent particulars ever existed, but it is impossible to (...) explain this by appealing to the powers of some actual thing or things to bring it about. I argue instead that dispositionalism, in the simple form championed by its proponents, is formally inadequate. Dispositionalists interpret the modal operators as simple existential claims about powers, but if we interpret the operators that way, the resulting system of modal logic is too weak to capture metaphysical modality. I argue that we can modify the standard dispositionalist interpretations of the operators to secure formal adequacy, but at the cost of accepting that not all modality is grounded in powers. This, I shall suggest, is not a bad thing—the resulting theory still has powers at its core and has certain attractive features, in addition to formal adequacy, that the standard theory lacks. (shrink)

The subject of the first section is Carnapian modal logic. One of the things I will do there is to prove that certain description principles, viz. the ''self-predication principles'', i.e. the principles according to which a descriptive term satisfies its own descriptive condition, are theorems and that others are not. The second section will be devoted to Carnapian modal arithmetic. I will prove that, if the arithmetical theory contains the standard weak principle of induction, modal truth (...) collapses to truth. Then I will propose a different formulation of Carnapian modal arithmetic and establish that it is free of collapse. Noteworthy is that one can retain the standard strong principle of induction. I will occupy myself in the third section with Carnapian epistemic logic and arithmetic. Here too it is claimed that the standard weak principle of induction is invalid and that the alternative principle is valid. In the fourth and last section I will get back to the self-predication principles and I will point to some of the consequences if one adds them to Carnapian Epistemic arithmetic. The interaction of self-predication principles and the strong principle of induction results in a collapse of de re knowability. (shrink)

In his program of analytic pragmatism, Robert Brandom has presented a thoroughgoing reinterpretation of the place of analytic philosophy in the history of philosophy by linking his own non-representational ‘inferentialist’ approach to semantics to the rationalist – idealist tradition, and in particular, to Hegel. Brandom, however, has not been without his critics in regard to both his approach to semantics and his interpretation of Hegel. Here I single out four interlinked problematic areas facing Brandom's inferentialist semantics – his approach of (...) perceptual content, to de re attitudes, to perceptual experience and to modality, and then go on to contrast the different approach to these issues that is found in Hegel. While Hegel can helpfully be understood as anticipating an inferentialist semantics as Brandom claims, his is a weak inferentialism in contrast to Brandom's strong version. With his weakly inferentialist approach Hegel can, I suggest, be seen as providing a solution to the tangle of problems.. (shrink)

One common objection against the Principle of Sufficient Reason is that it leads to a highly counterintuitive position, namely, necessitarianism. In this paper, drawing on Avicenna’s modal theory, I differentiate between two versions of necessitarianism: strong necessitarianism and weak necessitarianism. I argue that the modal intuition driving this objection pertains to strong necessitarianism, while the Principle of Sufficient Reason, at most, leads to weak necessitarianism.

This essay expands upon the suggestion that Lessing's infamous ‘ditch’ is actually three ditches: temporal, metaphysical, and existential gaps. It examines the complex problems these ditches raise, and then proposes that Kierkegaard's Fragments and Postscript exhibit a similar triadic organizational structure, which may signal a deliberate attempt to engage and respond to Lessing's three gaps. Viewing the Climacean project in this way offers an enhanced understanding of the intricacies of Lessing's rationalist approach to both religion and historical truth, and illuminates (...) Climacus's subjective response to Lessing. (shrink)

The traditional conception of risk is probabilistic, according to which the degree of risk of an event is determined by the probability of its occurence. Recently this view was challenged by Duncan Pritchard (2015, 2016), who suggested a modal theory of risk, centered in the idea that the riskiness of events depends on the modal distance between the actual world and worlds where the event obtains. What is attractive about this theory, according to Pritchard, is that it explains (...) our judgement about cases in which two equally probable events seem to have different degrees of risk. The modal theory of risk, however, has its own shortcomings: according to Bricker (2018), there are cases in which risk judgements are not tracking modal distance; there is also the problem of determining the risk of events that occur in the actual world, since the theory seems to imply that they are maximally risky because the actual world is maximally similar to itself (EBERT; SMITH; DURBACH, 2020). The modal conception of risk is also at odds with the most natural forms of reasoning over the morality of risk imposition. I begin exploring the two conceptions of risk, emphasizing their strenghts and weaknesses. I then argue that the probabilistic conception can be defended from objections, and a pluralistic theory of risk, although less unified, deserves to be considered. -/- . (shrink)

I propose a new reading of Hegel’s discussion of modality in the ‘Actuality’ chapter of the Science of Logic. On this reading, the main purpose of the chapter is a critical engagement with Spinoza’s modal metaphysics. Hegel first reconstructs a rationalist line of thought — corresponding to the cosmological argument for the existence of God — that ultimately leads to Spinozist necessitarianism. He then presents a reductio argument against necessitarianism, contending that as a consequence of necessitarianism, no adequate explanatory (...) accounts of facts about finite reality can be given. (shrink)

The idea that justified modal belief can be accounted for in terms of empirically justified, non-modal belief is enjoying increasing popularity in the epistemology of modality. One alleged reason to prefer modal empiricism over more traditional, rationalist modal epistemologies is that empiricism avoids the problem with the integration challenge that arise for rationalism, assuming that we want to be realists about modal metaphysics. In this paper, I argue that given two very reasonable constraints on (...) what it means to meet the integration challenge for modality, empiricism is currently at best on a par with, but potentially worse off than, rationalist alternatives, with respect to the integration challenge. (shrink)

Part 1 [Hodes, 2021] “looked under the hood” of the familiar versions of the classical propositional modal logic K and its intuitionistic counterpart. This paper continues that project, addressing some familiar classical strengthenings of K and GL), and their intuitionistic counterparts. Section 9 associates two intuitionistic one-step proof-theoretic systems to each of the just mentioned intuitionistic logics, this by adding for each a new rule to those which generated IK in Part 1. For the systems associated with the intuitionistic (...) counterparts of D and T, these rules are “pure one-step”: their schematic formulations does not use □ or ♢. For the systems associated with the intuitionistic counterparts of K4, etc., these rules meet these conditions: neither □ nor ♢ is iterated; none use both □ and ♢. The join of the two systems associated with each of these familiar logics is the full one-step system for that intuitionistic logic. And further “blended” intuitionistic systems arise from joining these systems in various ways. Adding the 0-version of Excluded Middle to their intuitionistic counterparts yields the one-step systems corresponding to the familiar classical logics. Each proof-theoretic system defines a consequence relation in the obvious way. Section 10 examines inclusions between these consequence relations. Section 11 associates each of the above consequence relations with an appropriate class of models, and proves them sound with respect to their appropriate class. This allows proofs of some failures of inclusion between consequence relations. Section 12 proves that the each consequence relation is complete or weakly complete, that relative to its appropriate class of models. The Appendix presents three further results about some of the intuitionistic consequence relations discussed in the body of the paper. For Keywords, see Part 1. (shrink)

The distinction between true belief and knowledge is one of the most fundamental in philosophy, and a remarkable effort has been dedicated to formulating the conditions on which true belief constitutes knowledge. For decades, much of this epistemological undertaking has been dominated by a single strategy, referred to here as the modal approach. Shared by many of the most widely influential constraints on knowledge, including the sensitivity, safety, and anti-luck/risk conditions, this approach rests on a key underlying assumption — (...) the modal profiles available to known and unknown beliefs are in some way asymmetrical. The first aim of this paper is to deconstruct this assumption, identifying its plausibility with the way in which epistemologists frequently conceptualize human perceptual systems as excluding certain varieties of close error under conditions conducive to knowledge acquisition. The second aim of this paper is to then argue that a neural phase phenomenon indicates that this conceptualization is quite likely mistaken. This argument builds on the previous introduction of this neural phase to the context of epistemology, expanding the use of neural phase cases beyond relatively narrow questions about epistemic luck to a much more expansive critique of the modal approach as a whole. (shrink)

I argue that recent rationalists' accounts of a priori knowledge suffer from two substantial weaknesses: an inadequate phenomenology of a priori insight , and the error of psychologism. I show that Husserl's theory of a priori knowledge presents a defensible and viable alternative for the contemporary rationalist, an alternative that addresses both the ontology and phenomenology of rational intuition, as well as such contemporary concerns as the possibility and character of a priori error, the empirical defeasibility of a priori claims, (...) the relation of mind to necessity, and the role of conception and imagination in a priori knowledge. Consequently, I conclude that Husserl's theory provides the needed response to the 20 th century critique of rationalism, and its attendant a priorism, as mysterious and obscure. (shrink)

After qualifying in which sense ‘realism’ can be applied to eighteenth-century views about morality, I argue that while Kant shares with traditional moral realists several fundamental claims about morality, he holds that those claims must be argued for in a radically different way. Drawing on his diagnosis of the serious weaknesses of traditional moral realism, Kant proposes a novel approach that revolves around a hybrid view about moral obligation. Since his solution to that central issue combines elements of realism with (...) elements of voluntarist ascent, Kant’s position can be characterized as an idealist version of moral realism or, more specifically, as the combination of a strong realism about the moral law with an idealist account of moral obligation. (shrink)

Reasons for action is a widely employed methodology in practical philosophy, and especially in moral philosophy. Reasons are facts that explain and justify actions. But, conceptually, if reasons were causes, incontinent actions would be impossible. When an agent ranks an evaluation about what to do as his best judgement, it entails that he has a reason for acting as that judgement prescribes. But when an agent acts incontinently, he acts in accordance to an intention that is not aligned with his (...) best evaluative judgement. Yet, if the agent’s best evaluative judgement provides him a reason for action, this reason should also be his strongest reason, and therefore, the strongest cause. How then can it be possible that an agent incontinently acts according to a reason of inferior causal strength? In this paper, I analyze how Davidson’s argument for the possibility of incontinent actions interacts with his causal theory of actions. I argue that Davidson’s proposal does not fully respect the two principles of intentional rationality, that he himself claims to be compelling. Lastly, I sketch some initial steps that might be helpful to drawing more precise conceptual distinctions in terms of the rationality of incontinent actions. (shrink)

Several of the most compelling anti-materialist arguments are motivated by the supposed existence of an unbridgeable epistemic gap between first-person subjective knowledge about one’s own conscious experience and third-personally acquired knowledge. The two with which this paper is concerned are Frank Jackson’s ‘knowledge argument’ and David Chalmers’s ‘modal argument’. The knowledge argument and the modal argument are often taken to function as ‘two sides of the same coin … in principle each succeeds on its own, but in practice (...) they work best in tandem’. This paper disagrees with the above claim, and argues that when considered together the knowledge argument and modal arguments illuminate each other’s weaknesses. These weaknesses become apparent when we acknowledge the epistemic richness of the cognitive aspect of perceptual experience, and question the epistemic role that any non-cognitive aspect might play. Closer examination of judgments about what it’s like to have a perceptual experience reveals fundamental problems with the knowledge argument, and when these problems are exposed, the two arguments can no longer ‘buttress each other where help is needed’. It becomes clear that neither is likely to succeed on its own, and when taken together both are destabilized. (shrink)

The purpose of this study is to propose new similarity measures namely rough variational coefficient similarity measure under the rough neutrosophic environment. The weighted rough variational coefficient similarity measure has been also defined. The weighted rough variational coefficient similarity measures between the rough ideal alternative and each alternative are xxxxx calculated to find the best alternative. The ranking order of all the alternatives can be determined by using the numerical values of similarity measures. Finally, an illustrative example has been provided (...) to show the effectiveness and validity of the proposed approach. Comparisons of decision results of existing rough similarity measures have been provided. (shrink)

This paper is devoted to present Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method for multi-attribute group decision making under rough neutrosophic environment. The concept of rough neutrosophic set is a powerful mathematical tool to deal with uncertainty, indeterminacy and inconsistency. In this paper, a new approach for multi-attribute group decision making problems is proposed by extending the TOPSIS method under rough neutrosophic environment. Rough neutrosophic set is characterized by the upper and lower approximation operators and the (...) pair of neutrosophic sets that are characterized by truth-membership degree, indeterminacy membership degree, and falsity membership degree. In the decision situation, ratings of alternatives with respect to each attribute are characterized by rough neutrosophic sets that reflect the decision makers’ opinion. Rough neutrosophic weighted averaging operator has been used to aggregate the individual decision maker’s opinion into group opinion for rating the importance of attributes and alternatives. Finally, a numerical example has been provided to demonstrate the applicability and effectiveness of the proposed approach. (shrink)