The book presents Transparent Intensional Logic in several of its latest realisations in such a way that it makes a case for the system and demonstrates how the theory can be applied to a wide range of cases.

In this paper, we examine a number of relevant logics’ variable sharing properties from the perspective of theories of topic or subject-matter. We take cues from Franz Berto’s recent work on topic to show an alignment between families of variable sharing properties and responses to the topic transparency of relevant implication and negation. We then introduce and defend novel variable sharing properties stronger than strong depth relevance—which we call cn-relevance and lossless cn-relevance—showing that the properties are satisfied by the (...) weak relevant logics and , respectively. We argue that such properties address a sort of semantic lossiness of strong depth relevance. (shrink)

This paper explores the logical consequences of the the thesis that all of the essential properties of consciousness can be known introspectively (Completeness, called "Strong Transparency" in the paper, following D.M. Armstrong's older terminology). It is argued that it can be known introspectively that consciousness does not have complete access to its essential properties; and it is show how this undermines conceivability arguments for dualism.

This paper shows how to conservatively extend classical logic with a transparent truth predicate, in the face of the paradoxes that arise as a consequence. All classical inferences are preserved, and indeed extended to the full (truth—involving) vocabulary. However, not all classical metainferences are preserved; in particular, the resulting logical system is nontransitive. Some limits on this nontransitivity are adumbrated, and two proof systems are presented and shown to be sound and complete. (One proof system allows for Cut—elimination, but (...) the other does not.). (shrink)

The book is about logical analysis of natural language. Since we humans communicate by means of natural language, we need a tool that helps us to understand in a precise manner how the logical and formal mechanisms of natural language work. Moreover, in the age of computers, we need to communicate both with and through computers as well. Transparent Intensional Logic is a tool that is helpful in making our communication and reasoning smooth and precise. It deals with all (...) kinds of linguistic context in a fully compositional and anti-contextual way. (shrink)

It is shown that: classicality is connected with various criteria some of which are fulfilled by TIL while some other are not; some more general characteristic of classicality connects it with philosophical realism whereas anti-realism is connected with non-classical logics; TIL is highly expressive due to its hyperintensionality, which makes it possible to handle procedures as objects sui generis. Thus TIL is classical in obeying principles of realism and non-classical in transcending some principles taught by textbooks of classical logic.

In Voyous, Jacques Derrida develops his argument starting from the presupposition that democracy as such is the entity whose integrity and immunity are at stake and, therefore, under investigation. This gesture reflects the setting in which ten years before, in Foi et savoir, he had cast his reasoning about the logic of immunity. There, it was one of the sources of religion, the immunity of the sacred, that operated according to this logic. The hyphen between these two essays, beside Derrida’s (...) own crossed references, is the genealogical reasoning on the meaning and essence of the concept of democracy: contrary to what Derrida claims, it will be maintained that Athenian democracy had a clear immune matrix, whose constant exercise is clearly defined, in spite of himself, by Vernant, and it will be shown how modern democracy has been forced to change policy. Modern democracy is an entity characterized by an immune deficiency. In order to save Derrida’s intuition from both the collapse of different vantage points and from a quite bizarre reticence in taking into account of the immune value of rituals, our starting point will be René Girard’s œuvre and his reading of the role of immune logic in sacred systems and, more generally, in modernity. The threshold between the auto-immune reaction, immune deficiency and auto-immune disease, between the sacrifice who delimits and constitutes the self and the holocauste du peuple en détail, is the space where, constantly exposed to the risk of auto-denial, democracy lives. (shrink)

In this essay we develop a theory of discourse reports. The theory provides a common set of structural and interpretive principles that together account for the truth conditions of direct, indirect and mixed reports. A distinguishing feature of our view is the assumption that the complement sentence of a report divides exclusively and exhaustively into regions that characterize the content of the reported utterance and regions that characterize the form of the utterance. This assumption implies that mixed reports do not (...) imply full direct or indirect reports. We discuss a classical David‐sonian proposal by Herman Cappelen and Ernest Lepore which conflicts with our theory on this latter point and show that it is unable to account for many of the phenomena we discuss. (shrink)

Starting with the observation that transparency has become a concept so familiar that one hardly ever stops to consider the presuppositions and consequences of its usage, the chapter analyses transparency demands as a specific way of exercising power. By doing so, the author shows that the intrinsic logic of transparency leads to paradoxical effects. Any attempts to realize complete transparency undermine its own preconditions. As Vogelmann argues, instead of providing more visibility and clarity, transparency makes its objects “invisible” and the (...) intensification of transparency demands produces self-censorship. The chapter concludes that transparency claims undermine the distinction between the private and the public and threaten the individual autonomy. (shrink)

This paper presents several important results for Transparent Intensional Logic (TIL). The conversions that are standardly taken to be valid – namely restricted β-conversion by name and β-reduction by value – are shown to be invalid. The core principle on which their validity is based – the so-called Compensation Principle – is also shown to be invalid. Further, the paper demonstrates the flaws of the proof of the Compensation Principle.

This paper presents several important results for Transparent Intensional Logic. The conversions that are standardly taken to be valid – namely restricted β-conversion by name and β-reduction...

For Tarski logics, there are simple criteria that enable one to conclude that two premise sets are equivalent. We shall show that the very same criteria hold for adaptive logics, which is a major advantage in comparison to other approaches to defeasible reasoning forms. A related property of Tarski logics is that the extensions of equivalent premise sets with the same set of formulas are equivalent premise sets. This does not hold for adaptive logics. However a (...) very similar criterion does. We also shall show that every monotonic logic weaker than an adaptive logic is weaker than the lower limit logic of the adaptive logic or identical to it. This highlights the role of the lower limit for settling the adaptive equivalence of extensions of equivalent premise sets. (shrink)

In Transparent Intensional Logic we can recognize two distinct notions of computation that loosely correspond to term rewriting and term interpretation as known from lambda calculus. Our goal will be to further explore these two notions and examine some of their properties.

In a 2010 paper Daley argues, contra Fodor, that several syntactically simple predicates express structured concepts. Daley develops his theory of structured concepts within Tichý’s Transparent Intensional Logic . I rectify various misconceptions of Daley’s concerning TIL. I then develop within TIL an improved theory of how structured concepts are structured and how syntactically simple predicates are related to structured concepts.

The American Journal of Bioethics, Volume 12, Issue 9, Page 45-47, September 2012.

It is sometimes objected that Tichý’s logic is not a logic because it underestimates deduction, providing only logical analyses of expressions. I argue that this opinion is wrong. First of all, to detect valid arguments, which are formulated in a language, there needs to be logical analysis to ascertain which semantical entities are involved. Entailment is defined as an extralinguistic affair relating those constructions. The validity of an argument, composed of propositional constructions, stems from the properties of the constructions. Such (...) properties are displayed by the derivation rules of Tichý’s system of deduction. (shrink)

We demonstrate how to validly quantify into hyperintensional contexts involving non-propositional attitudes like seeking, solving, calculating, worshipping, and wanting to become. We describe and apply a typed extensional logic of hyperintensions that preserves compositionality of meaning, referential transparency and substitutivity of identicals also in hyperintensional attitude contexts. We specify and prove rules for quantifying into hyperintensional contexts. These rules presuppose a rigorous method for substituting variables into hyperintensional contexts, and the method will be described. We prove the following. First, it (...) is always valid to quantify into hyperintensional attitude contexts and over hyperintensional entities. Second, factive empirical attitudes validate, furthermore, quantifying over intensions and extensions, and so do non-factive attitudes, both empirical and non-empirical , provided the entity to be quantified over exists. We focus mainly on mathematical attitudes, because they are uncontroversially hyperintensional. (shrink)

This paper presents and defends a way to add a transparent truth predicate to classical logic, such that and A are everywhere intersubstitutable, where all T-biconditionals hold, and where truth can be made compositional. A key feature of our framework, called STTT (for Strict-Tolerant Transparent Truth), is that it supports a non-transitive relation of consequence. At the same time, it can be seen that the only failures of transitivity STTT allows for arise in paradoxical cases.

In his paper ‘The logic of temporal discourse’, Pavel Tichý pointed out that contemporary systems of logic were unable to sufficiently formalise tenses. He therefore suggested temporal specification in transparent intensional logic (TIL), a system of logic that he developed. Discussing contemporary systems of logic, Tichý also took into account the system of Arthur N. Prior, who developed the first systems of modern temporal logic, and his criticism was also addressed to Prior. Tichý only focused, however, on Prior’s early (...) systems of temporal logic. Patrick Blackburn recently raised the awareness that Prior also developed systems of hybrid logic in his latest periods. From the point of view of temporal specification, this system is particularly interesting as the system has greater expressive power than Prior’s early systems of temporal logic. It could also consequently deal with the problematic specifications of tenses that Pavel Tichý pointed out. It is not only the formal criterion that make Tichý and Prior’s approach suitable for comparison. Both logicians shared similar views on time and logic. All these convictions also influenced their systems of logic. The aim of this paper is to demonstrate that the temporal propositions that Tichý introduced as problematic could be formalised in Prior’s hybrid temporal logic. I will also compare formalisations in TIL and hybrid logic and Tichý and Prior’s views that influenced their systems of logic. (shrink)

Pavel Tichy (1936-1994) was a Czech philosopher who originally studied and worked at Charles University in Prague, and spent the second half of his life in New Zealand as a political refugee. Early in his career he invented intensional logic, simultaneously with Richard Montague, but published his version in 1971, slightly after Montague's 1970 papers, and has never been recognised for this achievement. But this was only the beginning of his work. He developed a highly original theory of semantics called (...) Transparent Intensional Logic, which is the basis of an important research program based in the Czech Republic and Slovenia. He published a wide range of original work in semantics, philosophy of logic and language, philosophy of science, and metaphysics; but despite the indisputable quality of this work, he has gained little contemporary recognition. This article provides a brief introduction to his work, focussing mainly on basic ideas of his intensional semantics and his theory of 'constructions'. (shrink)

This paper defends the claim that although ‘Superman is Clark Kent and some people who believe that Superman flies do not believe that Clark Kent flies’ is a logically inconsistent sentence, we can still utter this sentence, while speaking literally, without asserting anything false. The key idea is that the context-sensitivity of attitude reports can be - and often is - resolved in different ways within a single sentence.

The recent wave of whistleblowers and cyber-dissidents, from Julian Assange to Edward Snowden, has declared war against surveillance. In this context, transparency is presented as an attainable political goal that can be delivered in flesh and bones by spectacular and quasi-messianic moments of disclosure. The thesis of this article is that, despite its progressive promise, the project of releasing classified documents is in line with the Orwellian cold war trope of Big Brother rather than with the complex geography of surveillance (...) today. By indicting the US federal government as the principal agent of surveillance, the ‘logic of the leak’ obfuscates that today’s surveillance is conducted mostly by the private sector in the form of dataveillance. What should we think, then, of this new fetish of transparency? Is it a symptom of the castigation of a desire for surveillance, the wish to be constantly observed and closely inspected? I claim that the meaning of the ‘expository society’, as Bernard Harcourt calls it, depends on how we interpret secrets. For secrets are not only temporary conditions of occultation that can, and should, be indiscriminately exposed, but sites of agency. In this perspective, the emancipatory promise hangs on the right to the secret, assumed as the right not to answer and not to belong. (shrink)

We prove how to validly quantify into hyperpropositional contexts de dicto in Transparent Intensional Logic. Hyperpropositions are sentential meanings and attitude complements individuated more finely than up to logical equivalence. A hyperpropositional context de dicto is a context in which only co-hyperintensional propositions can be validly substituted. A de dicto attitude ascription is one that preserves the attributee’s perspective when one complement is substituted for another. Being an extensional logic of hyperintensions, Transparent Intensional Logic validates all the rules (...) of extensional logic, including existential quantification. Yet the rules become more exacting when applied to hyperintensional contexts. The rules apply to only some types of entities, because the existence of only some types of entities is entailed by a hyperpropositional attitude de dicto. The insight that the paper offers is how a particular logic of hyperintensions is capable of validating quantifying-in in a principled and rigorous manner. This result advances the community-wide understanding of how to logically manipulate hyperintensions. (shrink)

Boghossian argued that externalism is incompatible with a transparency thesis according to which we can know a priori whether any two of our occurrent thoughts have the same or distinct content, and that this transparency thesis is integral to our commonsense conception of rationality, which requires the apriority of our logical abilities. Stalnaker offered a detailed compatibilist response to Boghossian. Boghossian criticized this response, and Stalnaker replied. But the outcome of that important discussion remained unclear, partly because it was unclear (...) how to understand the amended transparency thesis at which Stalnaker was gesturing. My aim in this paper is to settle the matter. I wish to clarify the terms of the debate, also by highlighting the relevant commitments of Stalnaker’s two-dimensionalist account, and to show that his compatibilist response, which appeals to diagonal propositions, is unsuccessful. (shrink)

If contextual values can play necessary and beneficial roles in scientific research, to what extent should science communicators be transparent about such values? This question is particularly pressing in contexts where there appears to be significant resistance among some non-experts to accept certain scientific claims or adopt science-based policies or recommendations. This paper examines whether value transparency can help promote non-experts’ warranted epistemic trust of experts. I argue that there is a prima facie case in favor of transparency because (...) it can promote four conditions that are thought to be required for epistemic trustworthiness. I then consider three main arguments that transparency about values is likely to be ineffective in promoting such trust (and may undermine it). This analysis shows that while these arguments show that value transparency is not sufficient for promoting epistemic trust, they fail to show that rejecting value transparency as a norm for science communicators is more likely to promote warranted epistemic trust than a qualified norm of value transparency (along with other strategies). Finally, I endorse a tempered understanding of value transparency and consider what this might require in practice. (shrink)

This paper is the twin of (Duží and Jespersen, in submission), which provides a logical rule for transparent quantification into hyperprop- ositional contexts de dicto, as in: Mary believes that the Evening Star is a planet; therefore, there is a concept c such that Mary be- lieves that what c conceptualizes is a planet. Here we provide two logical rules for transparent quantification into hyperpropositional contexts de re. (As a by-product, we also offer rules for possible- world propositional (...) contexts.) One rule validates this inference: Mary believes of the Evening Star that it is a planet; therefore, there is an x such that Mary believes of x that it is a planet. The other rule validates this inference: the Evening Star is such that it is believed by Mary to be a planet; therefore, there is an x such that x is believed by Mary to be a planet. Issues unique to the de re variant include partiality and existential presupposition, sub- stitutivity of co-referential (as opposed to co-denoting or synony- mous) terms, anaphora, and active vs. passive voice. The validity of quantifying-in presupposes an extensional logic of hyperinten- sions preserving transparency and compositionality in hyperinten- sional contexts. This requires raising the bar for what qualifies as co-denotation or equivalence in extensional contexts. Our logic is Tichý’s Transparent Intensional Logic. The syntax of TIL is the typed lambda calculus; its highly expressive semantics is based on a procedural redefinition of, inter alia, functional abstraction and application. The two non-standard features we need are a hyper- intension (called Trivialization) that presents other hyperintensions and a four-place substitution function (called Sub) defined over hy- perintensions. (shrink)

The recent wave of whistleblowers and cyber-dissidents, from Julian Assange to Edward Snowden, has declared war against surveillance. In this context, transparency is presented as an attainable political goal that can be delivered in flesh and bones by spectacular and quasi-messianic moments of disclosure. The thesis of this article is that, despite its progressive promise, the project of releasing classified documents is in line with the Orwellian cold war trope of Big Brother rather than with the complex geography of surveillance (...) today. By indicting the US federal government as the principal agent of surveillance, the ‘logic of the leak’ obfuscates that today’s surveillance is conducted mostly by the private sector in the form of dataveillance. What should we think, then, of this new fetish of transparency? Is it a symptom of the castigation of a desire for surveillance, the wish to be constantly observed and closely inspected? I claim that the meaning of the ‘expository society’, as Bernard Harcourt calls it, depends on how we interpret secrets. For secrets are not only temporary conditions of occultation that can, and should, be indiscriminately exposed, but sites of agency. In this perspective, the emancipatory promise hangs on the right to the secret, assumed as the right not to answer and not to belong. (shrink)

Transparency in business and society is one of the challenges raised in the encyclical Caritas in Veritate by Benedict XVI. This paper focuses on the issue by extending the literature on business ethics, corporate social responsibility, and corporate transparency in two dimensions. First, it reviews the understanding and framing of the transparency issue in Caritas in Veritate and in a selection of relevant Catholic Social Teaching (CST) publications. Second, this paper provides normative indications for corporate transparency decisions which reflect four (...) permanent principles of CST, that is, the common good, solidarity, subsidiarity, and respect for the human being. Inasmuch as human beings are worthy of love for their own sakes, the dimension of gift should always be present in relationships among them. This paper also provides insights for further studies on corporate transparency and the impact of religion on business ethics and corporate social responsibility. (shrink)

Adding a transparent truth predicate to a language completely governed by classical logic is not possible. The trouble, as is well-known, comes from paradoxes such as the Liar and Curry. Recently, Cobreros, Egré, Ripley and van Rooij have put forward an approach based on a non-transitive notion of consequence which is suitable to deal with semantic paradoxes while having a transparent truth predicate together with classical logic. Nevertheless, there are some interesting issues concerning the set of metainferences validated (...) by this logic. In this paper, we show that this logic, once it is adequately understood, is weaker than classical logic. Moreover, the logic is in a way similar to the paraconsistent logic LP. (shrink)

Epistemic transparency tells us that, if an agent S knows a given proposition p , then S knows that she knows that p . This idea is usually encoded in the so-called KK principle of epistemic logic. The paper develops an argument in favor of a moderate version of KK , which I dub quasi-transparency , as a normative rather than a descriptive principle. In the second Section I put forward the suggestion that epistemic transparency is not a demand of (...) ideal rationality, but of ideal epistemic responsibility, and hence that ideally responsible agents verify transparency principles of some sort; I also contend that their satisfaction should not be tied to an internalist epistemology. The central argument in favor of transparency is then addressed in Sections 3 to 8, through the development of a formal system. I show that, in a well-behaved formal setting, a moderate version of transparency is imposed upon us as a result of a number of independent decisions on the structure of higher-order probabilities, as long as we request that our probability and knowledge attributions cohere with each other. Thus I give a rationale to build a model for a hierarchy of languages with different levels of knowledge and probability operators; we obtain an analogous to KK for successive knowledge operators without actually demanding transitivity. The formal argument reinforces the philosophical intuition that epistemic transparency is an important desideratum we should not be too ready to dismiss. (shrink)

Emotivists like Ayer claim that moral sentences are devoid of cognitive meaning since they only evince attitudinal approval or disapproval of actions. In this paper, I explore two non-classical sem...

Since the 1990s the so-called transparency of experience has played a crucial role in core debates in philosophy of mind. However, recent developments in the literature have made transparency itself quite opaque. The very idea of transparent experience has become quite fuzzy, due to the articulation of many different notions of transparency and transparency theses. Absent a unified logical space where these notions and theses can be mapped and confronted, we are left with an overall impression of conceptual chaos. (...) This is a problem, given the constant and ubiquitous references to transparency in the literature and its prominent position in the contemporary philosophy of mind. My goal in this paper is to restore clarity through proper analysis of the mutual relations between the different transparency theses. This allows me to uncover a unitary multidimensional logical space where existing (as well as possible) views can be properly singled out and located. (shrink)

The paradoxical logic of transparency and mediation Transparency is the metaphor of our time. Whether in government or corporate governance, finance, technology, health or the media – it is ubiquitous today, and there is hardly a current debate that does not call for more transparency. But what does this word actually stand for and what are the consequences for the life of individuals? Can knowledge from the arts, and its play of visibility and invisibility, tell us something about the paradoxical (...) logics of transparency and mediation? This Obscure Thing Called Transparency gathers contributions by international experts who critically assess the promises and perils of transparency today. (shrink)

In his paper “Explaining Deductive Inference” Prawitz states what he calls «a fundamental problem of logic and the philosophy of logic»: the problem of explaining «Why do certain inferences have the epistemic power to confer evidence on the conclusion when applied to premisses for which there is evidence already?». In this paper I suggest a way of articulating, and partly modifying, the intuitionistic answer to this problem in such a way as to both answer Prawitz’s problem and satisfy a requirement (...) I argue to be crucial for any epistemic theory of the meaning of the logical constants: the requirement that evidence is epistemically transparent. (shrink)

This article proposes that the prime ideals of the university - those of truth, knowledge, justice, and emancipation - are also those that currently produce unjust practices "outside" and "within". Using the work of Jacques Derrida and Paul Virilio, the article argues that the central problem of the university today consists not so much of a neo-liberalisation, but of the speeding-up of these ideals through their enmeshment with techniques of calculation, vision, and prediction. The current university therefore suffers from what (...) it with Derrida identifies as an "auto-immune disease," in which the acceleration of its foundational aspirations have led to a near-total subjugation of all and everything to an oppressive quest for transparency. However, the article proposes via Virilio that this totalising transparency paradoxically also produces more blindness, accidents, and unknowability. It hopes to illustrate this with some examples in the teaching scene as well by working through some of its own conceptual tensions. The other logic of the university today, the article finally proposes, consists of a "dark" or stealth functionality, opening up the promise of a radically different future and unanticipated resistance despite itself. (shrink)

Do facts about water have a priori, transparent, reductive explanations in terms of microphysics? Ned Block and Robert Stalnaker hold that they do not. David Chalmers and Frank Jackson hold that they do. In this paper I argue that Chalmers.

Free logic is an important field of philosophical logic that first appeared in the 1950s. J. Karel Lambert was one of its founders and coined the term itself. The essays in this collection explore the philosophical foundations of free logic and its application to areas as diverse as the philosophy of religion and computer science. Amongst the applications on offer are those to the analysis of existence statements, to definite descriptions and to partial functions. The volume contains a proof that (...) free logics of any kind are non-extensional and then uses that proof to show that Quine's theory of predication and referential transparency must fail. The purpose of this collection is to bring an important body of work to the attention of a new generation of professional philosophers, computer scientists and mathematicians. (shrink)

This article is about the problem of non-disclosure of an assumed method and approach to international law. That makes some real and current issues of international more difficult to grasp – and how to debate about something if there is a misunderstanding of the basics? The problem is depicted with two examples: the attitude of international law toward the statehood of Taiwan along with the on-going development of the Responsibility to Protect doctrine. Both reveal the clash between so-called black-letterism and (...) a policy-approach to international law. Meanwhile the doctrinal method is fully functional and mostly accepted in domestic law, though often contested in international law. But after all, international law being sui generis law is not just an instance of the domestic-type law which is the effect of particular features of the international community. (shrink)

L'expérience de la connaissance nous enseigne qu'il n'y a pas de Réalité Dernière, que tout train en cache un autre. Une évidence qu'il n'est pas facile d'accepter, d'où l'idée de ce train ultime, celui qui ne cacherait plus rien. La transparentisme postule l'existence, au-delà de la perception immédiate, d'un monde, d'un niveau de lecture, complètement intelligible, i.e, explicite et immédiat. D'où cette croyance en de prétendus "rayons X du savoir" qui nous dévoileraient l'envers de l'Univers.

In Part 1 the reader is introduced to some standard systems of modal logic and encouraged through a series of exercises to become proficient in manipulating these logics. The emphasis is on possible world semantics for modal logics and the semantic emphasis is carried into the formal method, Jeffrey-style truth-trees. Standard truth-trees are extended in a simple and transparent way to take possible worlds into account. Part 2 systematically explores the applications of modal logic to philosophical issues (...) such as truth, time, processes, knowledge and belief, obligation and permission. Accessible, authoritative, and assured, Modal Logics and Philosophy requires no more background than the completion of a standard introductory logic course. It will be welcomed not only by students looking for a bridge between introductory logic texts and the high-level technical literature but as a guide to, and exploration of, work at the forefront of logic and philosophy. (shrink)

The first edition, published by Acumen in 2000, became a prescribed textbook on modal logic courses. The second edition has been fully revised in response to readers' suggestions, including two new chapters on conditional logic, which was not covered in the first edition. "Modal Logics and Philosophy" is a fully comprehensive introduction to modal logics and their application suitable for course use. Unlike most modal logic textbooks, which are both forbidding mathematically and short on philosophical discussion, "Modal (...) class='Hi'>Logics and Philosophy" places its emphasis firmly on showing how useful modal logic can be as a tool for formal philosophical analysis. In part 1 of the book, the reader is introduced to some standard systems of modal logic and encouraged through a series of exercises to become proficient in manipulating these logics. The emphasis is on possible world semantics for modal logics and the semantic emphasis is carried into the formal method, Jeffrey-style truth-trees. Standard truth-trees are extended in a simple and transparent way to take possible worlds into account. Part 2 systematically explores the applications of modal logic to philosophical issues such as truth, time, processes, knowledge and belief, obligation and permission. (shrink)

Theories where truth is a naive concept fall under the following dilemma: either the theory is subject to Curry’s Paradox, which engenders triviality, or the theory is not trivial but the resulting conditional is too weak. In this paper we explore a number of theories which arguably do not fall under this dilemma. In these theories the conditional is characterized in terms of non-deterministic matrices. These non-deterministic theories are similar to infinitely-valued Łukasiewicz logic in that they are consistent and their (...) conditionals are quite strong. The difference is the following: while Łukasiewicz logic is \-inconsistent, the non-deterministic theories might turn out to be \-consistent. (shrink)

Human beings are among the species with the best color perception of all mammals. Yet, transparency can be perceived in scenes in which color cues point to opacity. Why do we ignore such color cues? Here we argue that colors, rather than being passively registered, must be actively recreated and then bound to other stimulus attributes. In this process, the visual system faces fundamental problems, some of which are logically impossible to solve. The resulting unreliability of color perception may go (...) some way toward explaining why color cues cannot usually veto transparency percepts. Other stimulus attributes, however, affect transparency perception strongly even though they are not processed in foolproof ways either. How come? We argue that our trichromatic color perception is likely to have been a late, and for that reason less than fully integrated, addition to an already existing visual system that was colorblind to red and green. (shrink)

Dutch Book Arguments (DBAs) have been invoked to support various requirements of rationality. Some are plausible: probabilism and conditionalization. Others are less so: credal transparency and reflection. Anna Mahtani has argued for a new understanding of DBAs which, she claims, allow us to keep the DBAs for probabilism (and perhaps conditionalization) and reject the DBAs for credal transparency and reflection. I argue that Mahtani’s new account fails as (a) it does not support highly plausible requirements of rational coherence and (b) (...) it does not, even setting aside the first objection, succeed in undermining the DBAs for credal transparency or reflection. (shrink)