How do people make deductions? The orthodox view in psychology is that they use formal rules of inference like those of a “natural deduction” system.Deductionargues that their logical competence depends, not on formal rules, but on mental models. They construct models of the situation described by the premises, using their linguistic knowledge and their general knowledge. They try to formulate a conclusion based on these models that maintains semantic information, that expresses it parsimoniously, and that makes explicit something not directly (...) stated by any premise. They then test the validity of the conclusion by searching for alternative models that might refute the conclusion. The theory also resolves long-standing puzzles about reasoning, including how nonmonotonic reasoning occurs in daily life. The book reports experiments on all the main domains of deduction, including inferences based on prepositional connectives such as “if” and “or,” inferences based on relations such as “in the same place as,” inferences based on quantifiers such as “none,” “any,” and “only,” and metalogical inferences based on assertions about the true and the false. Where the two theories make opposite predictions, the results confirm the model theory and run counter to the formal rule theories. Without exception, all of the experiments corroborate the two main predictions of the model theory: inferences requiring only one model are easier than those requiring multiple models, and erroneous conclusions are usually the result of constructing only one of the possible models of the premises. (shrink)

As it is indicated in the title, this paper is devoted to the problem of defining mereological (collective) sets. Starting from basic properties of sets in mathematics and differences between them and so called conglomerates in Section 1, we go on to explicate informally in Section 2 what it means to join many objects into a single entity from point of view of mereology, the theory of part of (parthood) relation. In Section 3 we present and motivate basic axioms for (...) part of relation and we point to their most fundamental consequences. Next three sections are devoted to formal explication of the notion of mereological set (collective set) in terms of sums, fusions and aggregates. We do not give proofs of all theorems. Some of them are complicated and their presentation would divert the reader’s attention from the main topic of the paper. In such cases we indicate where the proofs can be found and analyzed by those who are interested. (shrink)

History and the modern sciences are characterized by what is sometimes called a “methodological naturalism” that disregards talk of divine agency. Some religious thinkers argue that this reflects a dogmatic materialism: a non-negotiable and a priori commitment to a materialist metaphysics. In response to this charge, I make a sharp distinction between procedural requirements and metaphysical commitments. The procedural requirement of history and the sciences—that proposed explanations appeal to publicly-accessible bodies of evidence—is non-negotiable, but has no metaphysical implications. The metaphysical (...) commitment is naturalistic, but is both a posteriori and provisional, arising from the fact that formore than 400 years no proposed theistic explanation has been shown capable ofmeeting the procedural requirement. I argue that there is nothing to prevent religious thinkers from seeking to overturn this metaphysically naturalistic stance. But in order to do so they would need to show that their proposed theistic explanations are the best available explanations of a range of phenomena. Until this has been done, the metaphysical naturalism of history and the sciences remains defensible. (shrink)

Résumé Partant du principe que la philosophie de la connaissance de Poincaré est cohérente, j’essaie de faire voir que son conventionnalisme en géométrie et en physique n’est qu’une conséquence de son intuitionnisme. Après avoir rappelé, dans la première section, ce qu’est l’intuitionnisme et décrit ce que l’intuitionnisme de Poincaré a de spécifique, je montre, dans la deuxième section, comment celui-ci retentit sur la conception de l’espace. Dans la troisième section, j’applique les conclusions précédemment établies à la question très controversée de (...) la découverte de la relativité restreinte en renvoyant dos à dos les historiens : il n’a rien manqué à Poincaré pour découvrir la relativité restreinte, car, cette théorie étant incompatible avec son intuitionnisme, il n’avait aucune raison d’y adhérer.Taking for granted that Poincaré’s epistemology is consistent, I attempt to show that his geometrical and physical conventionalism is no more than a consequence of his intuitionism. After having rehearsed the issues defining intuitionism and describing what is particular to Poincaré’s version in the first section of the paper, I show, in the second section, how Poincaré’s intuitionism influenced his conception of space. In the last section, I apply these now established conclusions to a very contested issue, the discovery of the special theory of relativity. Rejecting the view of historians on both sides of the issue, I argue that Poincaré had everything he would have needed to discover the special theory of relativity, but that since this theory is incompatible with his intuitionism, he had no reason to adopt it. (shrink)

We propose another positive illusion that fits with McKay & Dennett's (M&D's) criteria for adaptive misbeliefs. This illusion is pervasive in adult reasoning but we focus on its prevalence in children's developing theories. It is a strongly held conviction arising from normal functioning of the doxastic system that confers adaptive advantage on the individual.

Hugo Mercier and Dan Sperber have proposed an “argumentative theory of rea-soning” in which the function of reasoning is to devise and evaluate arguments intended to persuade. Mercier and Sperber note that the theory does not work when we reason alone or with people who share our beliefs. However, the theory also fails in deliberations involving “framework beliefs”—beliefs that are only indirectly related to empirical evidence but that have a particular importance for the believer because of their centrality to a (...) dense web of other beliefs and their connections to social practices. Framework beliefs not only include many ethical, religious, and political beliefs, but also paradigmatic scientific beliefs. An alterna-tive theory of reasoning, derived from philosophical pragmatism, is presented that explains the rigidity of framework beliefs and is more optimistic about individual reasoning. A consequence of the pragmatist theory is that certain types of bias and polarization are functional. (shrink)

When asked to contribute to this lecture series, my first thought was to talk about philosophy of biology, a new and increasingly influential field in philosophy, surely destined to have great impact in the coming years. But when a preliminary schedule for the series was circulated, I noticed that no one was speaking on language. Given the hegemony of philosophy of language at mid-century, after ‘the linguistic turn’, this seemed to require comment. How did philosophy of language achieve such status (...) at mid-century, and why is it losing it now? Has the Anglo-American tradition really begun to put the philosophy of language in better perspective? I hope so. Indeed, I will end with suggestions for how to keep it more securely in its proper place. (shrink)

We can characterise thought in two different ways. Which is preferred can have implications for important issues about reasoning and the norms that govern cognition. The first, which owes much to the picture of the mind encountered in Descartes' Meditations, observes that paradigmatic examples of thoughts and inferences are events and processes whose special characteristics stem from their being ‘mental’ occurrences. For example they are conscious or, if unconscious, they stand in some special relation to thought processes that are conscious. (...) They typically involve attitudes towards contents or propositions. In general, thoughts have a distinctive onto-logical status and this status depends upon their being mental and typically conscious. The second emphasises that thought is a kind of activity with a definite function. It involves the use of intelligence to solve problems, answer questions, make plans and so on. Thought should be studied as a kind of goal-directed activity. Those interested in the norms that govern thought should attend to the role of responsible disciplined reflection in carrying out this activity. (shrink)

Recent years have witnessed an increasing number of attempts to reconstruct Marxian theory in forms that can be assessed by reference to currently received standards in various disciplines. The work has even been said to establish a new paradigm: “analytical Marxism.” One doesn't have to endorse this claim to recognize a good deal of merit in the work. Through creative application of state-of-the-art methods to traditional Marxian issues, researchers have promoted productive cross-fertilization with non-Marxian programs and have revealed many problems (...) that must be resolved for fruitful development of Marxian theory. Marx's work can be relevant to today's problems only if it is examined from vantage points provided by subsequent scientific and philosophical achievements. Moreover, critical engagement with the best science of the day has been an essential part of the Marxian theoretical project from the beginning. (shrink)

This thesis is on the history and philosophy of logic and semantics. Logic can be described as the ‘science of reasoning’, as it deals primarily with correct patterns of reasoning. However, logic as a discipline has undergone dramatic changes in the last two centuries: while for ancient and medieval philosophers it belonged essentially to the realm of language studies, it has currently become a sub-branch of mathematics. This thesis attempts to establish a dialogue between the modern and the medieval traditions (...) in logic, by means of ‘translations’ of the medieval logical theories into the modern framework of symbolic logic, i.e. formalizations. One of its conclusions is that, when properly understood within their own framework, the interest of medieval logical theories for modern investigations go beyond mere historical interest, but that a thorough conceptual analysis of such theories must be undertaken in order to avoid conceptual misprojections. While such translations of medieval into modern logic have been attempted before, the approach presented here is innovative in that attention is paid to the similarities as well as to the dissimilarities between the two traditions, and to what can be learned from the medieval masters for modern investigations in logic and semantics. (shrink)

This paper considers the connection between concepts, conceptual schemes and grammar in Wittgenstein’s last writings. It lists eight claims about concepts that one can garner from these writings. It then focuses on one of them, namely that there is an important difference between conceptual and factual problems and investigations. That claim draws in its wake other claims, all of them revolving around the idea of a conceptual scheme, what Wittgenstein calls a ‘grammar’. I explain why Wittgenstein’s account does not fall (...) prey to Davidson’s animadversions against the idea of a conceptual scheme as a force operating on a pre-conceptual content. In the sequel I deny that the distinction between grammatical and empirical propositions disappears in the last writings: it is neither deliberately abandoned, nor willy-nilly undermined by the admission of hinge propositions in On Certainty or by the role accorded to agreement in judgement. (shrink)

As demonstrated by several example displays, color illusions challenge color realism, because they involve a one-to-many reflectance-to-color mapping. Solving this problem by differentiating between veridical and illusory colors corresponding to the same reflectance is hampered because of the lack of an appropriate criterion. However, the difference between veridical and illusory color perception can still be maintained.

Vision scientists are interested in three diverse entities: physical stimuli, neural states, and consciously perceived colors, and in the mapping rules among the three. In this worldview, the three kinds of entities have coequal status, and views that attribute color exclusively to one or another of them, such as color realism, have no appeal.

Byrne & Hilbert propose that color can be identified with explicit properties of physical surfaces. I argue that this claim must be qualified to take into account constraints needed to make recovery of surface color information possible. When these constraints are satisfied, then a biological visual system can establish a correspondence between perceived surface color and specific surface properties.

Byrne & Hilbert's thesis, that color be associated with reflectance-type, is questioned on the grounds that it is far from clear that the human visual system is able to determine a surface's reflectance-type with sufficient accuracy. In addition, a (friendly) suggestion is made as to how to amend the definition of reflectance-type in terms of CIE (Commission Internationale de l'Eclairage) coordinates under a canonical illuminant.

The problem of nonreflectors perceived as colored is the central problem for Byrne & Hilbert's (B&H's) physicalism. Vision scientists and other interested parties need to consider the motivation for their account of “productance physicalism.” Is B&H's theory motivated by scientific concerns or by philosophical interests intended to preserve a physicalist account of color as a posteriori necessary?

We argue that any theory of color physicalism must include consideration of ecological interactions. Ecological and sensorimotor contingencies resulting from relative surface motion and observer motion give rise to measurable effects on the spectrum of light reflecting from surfaces. These contingencies define invariant manifolds in a sensory-spatial space, which is the physical underpinning of all subjective color experiences.

The present note will be concerned only with Sir Partha Dasgupta's recent article in this journal (Dasgupta 2005). What is more, it will concentrate on those parts of the article which contain a serious misreading of Hilary Putnam's position on the entanglement of facts, theories and values. These philosophical matters can perhaps be clarified for economist readers (they should require no clarification for philosophers) by considering, to begin with, Dasgupta's interpretation of the Bergson–Samuelson position. What (Bergson) Burk (1938) and Samuelson (...) (1947) were doing, according to Dasgupta, was to establish ‘the ethical foundations of the subject. . .over five decades ago’ (Dasgupta 2005: 221–2).2 Thus a major theme of the article is heard at once: economics is supposedly based on sound ethical foundations, and these can be traced (it is supposed) to specific work written long ago, and hence needing no augmentation. These ethical foundations, it is claimed, ‘are now regarded to be a settled matter’ (2005: 222). (shrink)

Scientific discourse leaves implicit a vast amount of knowledge, assumes that this background knowledge is taken into account – even taken for granted – and treated as undisputed. In particular, the terminology in the empirical sciences is treated as antecedently understood. The background knowledge surrounding a theory is usually assumed to be true or approximately true. This is in sharp contrast with logic, which explicitly ignores underlying presuppositions and assumes uninterpreted languages. We discuss the problems that background knowledge may cause (...) for the formalization of scientific theories. In particular, we will show how some of these problems can be addressed in the context of the computational representation of scientific theories. (shrink)

Jim Mackenzie; Evers & Walker and Forms of Knowledge, Journal of Philosophy of Education, Volume 19, Issue 2, 30 May 2006, Pages 199–209, https://doi.org/10.

If identity is to be taken as a relation, not between any object and itself, nor between expressions , but between "intensions" or Fregean "Sinnen" of individual constants , then not only definite descriptions but also grammatically proper names ought to have intensions. This, however, has been repudiated by J. St. Mill and, more recently and more persuasively, by Saul Kripke. So an attempt will be made to interpret proper names as definite descriptions sui generis, namely, "rigid" descriptions referring to (...) the way the bearer of the name is called, in certain contexts, in the real world. To avoid circularity or a vicious regressus in infinitum, however, one has to do this on the basis of a distinction between "names" and "name-radicals". (shrink)

Two fundamental categories of any ontology are the category of objects and the category of universals. We discuss the question whether either of these categories can be infinite or not. In the category of objects, the subcategory of physical objects is examined within the context of different cosmological theories regarding the different kinds of fundamental objects in the universe. Abstract objects are discussed in terms of sets and the intensional objects of conceptual realism. The category of universals is discussed in (...) terms of the three major theories of universals: nominalism, realism, and conceptualism. The finitude of mind pertains only to conceptualism. We consider the question of whether or not this finitude precludes impredicative concept formation. An explication of potential infinity, especially as applied to concepts and expressions, is given. We also briefly discuss a logic of plural objects, or groups of single objects (individuals), which is based on Bertrand Russell’s (1903, The principles of mathematics, 2nd edn. (1938). Norton & Co, NY) notion of a class as many. The universal class as many does not exist in this logic if there are two or more single objects; but the issue is undecided if there is just one individual. We note that adding plural objects (groups) to an ontology with a countable infinity of individuals (single objects) does not generate an uncountable infinity of classes as many. (shrink)

In order to understand consciousness one would benefit from developing a more eclectic intellectual style. Consciousness is, as proposed by almost everyone except the stubborn reductionists, a truly mysterious concept. Its study and dissection merits a multidisciplinary approach. Waving this multidisciplinary flag has positively enlarged the discussion and neurologists, psychiatrists, mathematicians, and so on, have moved to the philosophy of mind arena, first with caution and now with a more powerful voice. Identifying what we mean by consciousness is a first (...) step even when we want to deny its existence. The link between consciousness and some other mental activity is a logical next step and there is abundant literature doing this, but not all of them differentiate among associated yet different phenomena. (shrink)

Che cosa vuol dire per le espressioni del nostro linguaggio avere un significato? Secondo un approccio oggi sostanzialmente standard in semantica, avere significato vuol dire prima di tutto avere un contenuto rappresentazionale, cioè poter rappresentare qualcosa. Secondo un inferenzialista come Robert Brandom, invece, le espressioni del nostro linguaggio hanno contenuto perché sono inserite in una rete di relazioni inferenziali, rispetto alla quale possono essere utilizzate per dare e richiedere ragioni. Il libro di Pietro Salis, Pratiche discorsive razionali, presenta e discute (...) alcuni degli aspetti più interessanti dell'inferenzialismo normativo di Brandom. Si tratta della seconda monografia in lingua italiana dedicata alla filosofia del linguaggio brandomiana dopo quella di Giovagnoli (2004). Per trovare elementi di paragone con il lavoro di Salis occorre allora guardare alle pubblicazioni in lingua inglese. Tra queste ci sono le raccolte di saggi curate da Stekeler-Weithofer (2008), Prien e Schweikard (2008), e Weiss e Wanderer (2010). Ma anche le introduzioni monografiche di Wanderer (2008) e Turbanti (2017). La prima di queste introduzioni, in particolare, è quella più simile al libro di Salis, soprattutto dal punto di vista tematico. (shrink)

Recent defenders of Philippa Foot, such as Michael Thompson and John Hacker-Wright, have argued that it is a mistake to think that Ft aims to justify a substantive conception of human soundness and defect. instead, she relies on the acceptance of certain groundless moral norms to underwrite her views about what is characteristically human. I maintain that this is a weakness and that the Footian-style proponent of natural normativity needs to provide a story about how we might achieve justified self-confidence (...) regarding moral norms. In this paper, I offer a coherentist model for doing so, thereby addressing the justification gap. (shrink)

A definition of a property P is impredicative if it quantifies over a domain to which P belongs. Due to influential arguments by Ramsey and Gödel, impredicative mathematics is often thought to possess special metaphysical commitments. It seems that an impredicative definition of a property P does not have the intended meaning unless P already exists, suggesting that the existence of P cannot depend on its explicit definition. Carnap (1937 [1934], p. 164) argues, however, that accepting impredicative definitions amounts to (...) choosing a "form of language" and is free from metaphysical implications. This paper explains this view in its historical context. I discuss the development of Carnap’s thought on the foundations of mathematics from the mid-1920s to the mid-1930s, concluding with an account of Carnap’s (1937 [1934]) non-Platonistic defense of impredicativity. This discussion is also important for understanding Carnap’s influential views on ontology more generally, since Carnap’s (1937 [1934]) view, according to which accepting impredicative definitions amounts to choosing a "form of language", is an early precursor of the view Carnap presents in "Empiricism, Semantics and Ontology" (1956 [1950]), according to which referring to abstract entities amounts to accepting a "linguistic framework". (shrink)

Plural Logic is an extension of First-Order Logic with plural terms and quantifiers. When its plural terms are interpreted as denoting more than one object at once, Plural Logic is usually taken to be ontologically innocent: plural quantifiers do not require a domain of their own, but range plurally over the first-order domain of quantification. Given that Plural Logic is equi-interpretable with Monadic Second-Order Logic, it gives us its expressive power at the low ontological cost of a first-order language. This (...) makes it a valuable tool in various areas of philosophy. Some authors believe that Plural Logic can be extended into an even more expressive logic, Higher-Level Plural Logic, by adding higher-level plural terms and quantifiers to it. The basic idea is that second-level plurals stand to plurals like plurals stand to singulars. Allegedly, Higher-Level Plural Logic enjoys the expressive power of type theory while, again, committing us only to the austere ontology of a first-order language. Were this really the case, Higher-Level Plural Logic would be a very useful tool, extending and strengthening some of the applications of Plural Logic. However, while the notions of plural reference and quantification enjoy widespread acceptance today, their higher-level counterparts have been received with scepticism. The main objection raised against them is that higher-level plural reference is unintelligible. This has been argued, among others, on the grounds that there are no higher-level plurals in natural language and that, if there were any, they could be eliminated. In this thesis, after introducing the debate on plurals in Chapters 1 and 2, I turn to defending the legitimacy of the notion of higher-level plural reference. To this end, in Chapter 3, I present and elucidate the notion. Next, in Chapter 4, I show that some natural languages clearly contain these expressions and that they do so in an ineliminable manner. Finally, in Chapters 5 and 6, I develop a semantics for higher-level plurals that employs only devices previously well-understood by English speakers. To finish, in Chapter 7, I describe an application of Higher-level Plural Logic: a strengthening of the neo-Fregean programme. After describing my proposal, I turn to the issue of the logical status of this formalism and defend an optimistic take on the matter. (shrink)

I have argued elsewhere for a deflationary conception of metaphysics, which takes well-formed metaphysical questions to be answerable using nothing more mysterious than empirical information and descriptive and normative conceptual work. Here I examine the ways in which our practices of metaphysics should change, if we adopt the deflationary reconception of metaphysics. Adopting this approach does not mean abandoning metaphysics, but it does lead to important differences regarding which debates and positions are worth taking seriously. It also requires us to (...) reevaluate which criteria for choosing metaphysical views are appropriate – particularly where debates about existence are concerned. (shrink)

According to W. V. Quine, science advocates a physicalist ontology and an empiricist epistemology. However, Quine’s ontological physicalism includes the abstract objects of mathematics, such as numbers or sets. So, Quine’s commitments to empiricism are firm but not permanent. Quine has incorporated various elements of pragmatic thought into his philosophical outlook, that is why I advocate that Quine’s philosophy decidedly gives to the pragmatic view of empiricism.

Uncertainty is an intriguing aspect of social life. Uncertainty is epistemic, future-oriented, and implies that we can neither predict nor foresee what will happen when acting. In cases in which no institutionalized certainty about future states exists, or can be generated, judgment is needed. This article presents the forms by which uncertainty is reduced as a result of judgments made about different alternatives in a process involving several actors. This type of uncertainty may exist, for example, about which artist is (...) the best, which offer in the market is more valuable, which football team is better than all the rest, or which research proposal will get a grant. The result of different forms of uncertainty reduction is increased certainty concerning alternatives in relation to one another, such as good and bad, rank lists, scores, quality assessment, and “winner and losers.” Based on the result, uncertainty is reduced and action is facilitated. The forms are structural and comprise roles; may be legitimate in a smaller or larger domain; and may exist in all spheres of life, as exemplified in sports competitions, in labor markets, and in the ranking of universities. Three forms of uncertainty reduction based on judgment are identified in this article: (1) decision, made by an authority; (2) valuation, by means of which order arises as a result of actors ascribing values; and (3) contest, by which an order is the result of direct struggle. (shrink)

The broad aim of this thesis is to explore fruitful connections between ideology theory and the philosophy of possible worlds. Ideologies are full of modal concepts, such as possibility, potential, necessity, essence, contingency and accident. Typically, PWs are articulated for the analysis and illumination of modal concepts. That naturally suggests a method for theorising ideological modality, utilising PW theory. The specific conclusions of the thesis proffer a number of original contributions to knowledge: 1) PWs should only be used for explication (...) and not as evidence or criteria of assessment in ideology theory. The estimation of utopian possibilities, human essences and freedoms must be determined by extrinsic criteria. PWs can serve only as a window or means of expression but not as a set of evaluative premises. 2) For this purpose, a modified version of Lewisian genuine realism, with its device of counterpart theory, is the best approach; the alternative theories risk constricting possibilities or smuggling in assumptions that ought to be objects of analysis in ideology theory. This is instructive, since ideology theorists are prone to pick and choose favoured aspects of modal philosophy without further argument. 3) Conclusions and suggest the adoption of GR or fictionalist GR. Overall, the actualist options are less adequate. Fictionalism, by contrast, is a worthwhile contender, but it too presents comparative weaknesses which reinforce GR’s standing as a potent challenger to the modal metaphysician. Therefore, this thesis presents additional reasons to think GR true. The conclusions are not knockdown, and I draw out incentives and consequences for adopting alternative stances. The various chapters also provide specific details for comprehending and debating ideological modals. (shrink)

Jim Mackenzie; Evers & Walker and Forms of Knowledge, Journal of Philosophy of Education, Volume 19, Issue 2, 30 May 2006, Pages 199–209, https://doi.org/10.