There is ample evidence from literature and clinical practice indicating mathematical difficulties in individuals with ADHD, even when there is no concomitant diagnosis of developmental dyscalculia. What factors underlie these difficulties is still an open question. Research on dyscalculia and neurotypical development suggests visual perception of numerosity (the number sense) as a building block for math learning. Participants with lower numerosity estimation thresholds (higher precision) are often those with higher math capabilities. Strangely, the role of numerosity perception in math skills (...) in ADHD has been neglected, leaving open the question whether math difficulties in ADHD also originate from a deficitary visual number sense. In the current study we psychophysically measured numerosity thresholds and accuracy in a sample of children/adolescents with ADHD, but not concomitant dyscalculia (N = 20, 8–16 years). Math abilities were also measured by tasks indexing different mathematical competences. Numerosity performance and math scores were then compared to those obtained from an age-matched control group (N = 20). Bayesian statistics indicated no difference between ADHD and controls on numerosity perception, despite many of the symbolic math tasks being impaired in participants with ADHD. Moreover, the math deficits showed by the group with ADHD remained substantial even when numerosity thresholds were statistically regressed out. Overall, these results indicate that math difficulties in ADHD are unlikely to originate from an impaired visual number sense. (shrink)

Many philosophers have been attracted to the idea of using the logical form of a true sentence as a guide to the metaphysical grounds of the fact stated by that sentence. This paper looks at a particular instance of that idea: the widely accepted principle that disjunctions are grounded in their true disjuncts. I will argue that an unrestricted version of this principle has several problematic consequences and that it’s not obvious how the principle might be restricted in order to (...) avoid them. My suggestion is that, instead of trying to restrict the principle, we should distinguish between metaphysical and conceptual grounds and take the principle to apply exclusively to the latter. This suggestion, if correct, carries over to other prominent attempts at using logical form as a guide to ground. (shrink)

This paper defends the view that one's own mental states are metaphysically privileged vis-à-vis the mental states of others, even if only subjectively so. This is an instance of a more general view called Subjectivism, according to which reality is only subjectively the way it is. After characterizing Subjectivism in analogy to two relatively familiar views in the metaphysics of modality and time, I compare the Subjectivist View of the Mental with Egocentric Presentism, a version of Subjectivism recently advocated by (...) Caspar Hare. I argue that the Subjectivist View of the Mental goes a considerable way towards solving certain long-standing philosophical puzzles having to do with the unity of consciousness, the contents of self-awareness and the intransmissibility of experiential knowledge through testimony. (shrink)

Relativists make room for the possibility of “faultless disagreement” by positing the existence of subjective propositions, i.e. propositions true from some points of view and not others. We discuss whether the adoption of this position with respect to a certain domain of discourse is compatible with a realist attitude towards the matters arising in that domain. At first glance, the combination of relativism and realism leads to an unattractive metaphysical picture on which reality comprises incoherent facts. We will sketch the (...) contours of a realist-relativist position called “subjectivism”, which avoids this result by giving up the assumption that the points of view of different subjects are all metaphysically “on a par”. (shrink)

This paper argues that what is currently the most popular version of temporal Fragmentalism—‘unstructured’ temporal Fragmentalism, as I shall call it—faces a problem of Tensed Belief Explosion. Four possible solutions to this problem are reviewed and shown to be wanting; two more promising ones risk fostering scepticism about the existence of tensed facts—hence, about Fragmentalism itself. The tentative moral is that unstructured versions of Fragmentalism are at best unmotivated and at worst seriously flawed.

This paper discusses an argument by Norton to the effect that reversible processes in thermodynamics have paradoxical character, due to the infinite-time limit. For Norton, one can “dispel the fog of paradox” by adopting a distinction between idealizations and approximations, which he himself puts forward. Accordingly, reversible processes ought to be regarded as approximations, rather than idealizations. Here, we critically assess his proposal. In doing so, we offer a resolution of his alleged paradox based on the original work by Tatiana (...) Ehrenfest-Afanassjeva on the foundations of thermodynamics. (shrink)

We introduce a sequent calculus B for a new logic, named basic logic. The aim of basic logic is to find a structure in the space of logics. Classical, intuitionistic, quantum and non-modal linear logics, are all obtained as extensions in a uniform way and in a single framework. We isolate three properties, which characterize B positively: reflection, symmetry and visibility. A logical constant obeys to the principle of reflection if it is characterized semantically by an equation binding it with (...) a metalinguistic link between assertions, and if its syntactic inference rules are obtained by solving that equation. All connectives of basic logic satisfy reflection. To the control of weakening and contraction of linear logic, basic logic adds a strict control of contexts, by requiring that all active formulae in all rules are isolated, that is visible. From visibility, cut-elimination follows. The full, geometric symmetry of basic logic induces known symmetries of its extensions, and adds a symmetry among them, producing the structure of a cube. (shrink)

The first issue of Artificial Intelligence and Law journal was published in 1992. This paper provides commentaries on nine significant papers drawn from the Journal’s second decade. Four of the papers relate to reasoning with legal cases, introducing contextual considerations, predicting outcomes on the basis of natural language descriptions of the cases, comparing different ways of representing cases, and formalising precedential reasoning. One introduces a method of analysing arguments that was to become very widely used in AI and Law, namely (...) argumentation schemes. Two relate to ontologies for the representation of legal concepts and two take advantage of the increasing availability of legal corpora in this decade, to automate document summarisation and for the mining of arguments. (shrink)

Within the technical frame supplied by the algebraic variety of diagonalizable algebras, defined by R. Magari in [2], we prove the following: Let T be any first-order theory with a predicate Pr satisfying the canonical derivability conditions, including Löb's property. Then any formula in T built up from the propositional variables $q,p_{1},...,p_{n}$ , using logical connectives and the predicate Pr, has the same "fixed-points" relative to q (that is, formulas $\psi (p_{1},...,p_{n})$ for which for all $p_{1},...,p_{n}\vdash _{T}\phi (\psi (p_{1},...,p_{n}),p_{1},...,p_{n})\leftrightarrow \psi (...) (p_{1},...,p_{n})$ ) of a formula $\phi ^{\ast}$ of the same kind, obtained from φ in an effective way. Moreover, such $\phi ^{\ast}$ is provably equivalent to the formula obtained from φ substituting with $\phi ^{\ast}$ itself all the occurrences of q which are under Pr. In the particular case where q is always under Pr in φ, $\phi ^{\ast}$ is the unique (up to provable equivalence) "fixed-point" of φ. Since this result is proved only assuming Pr to be canonical, it can be deduced that Löb's property is, in a sense, equivalent to Gödel's diagonalization lemma. All the results are proved more generally in the intuitionistic case. (shrink)

There are two intuitions about time. The first is that there's something special about the present that objectively differentiates it from the past and the future. Call this intuition Specialness. The second is that the time at which we happen to live is just one among many other times, all of which are ‘on a par’ when it comes to their forming part of reality. Call this other intuition Egalitarianism. Tradition has it that the so-called ‘A-theories of time’ fare well (...) at addressing the first intuition, but rather badly when it comes to the second. The goal of this article is to offer advice to A-theorists about how to reconcile their view with Egalitarianism. (shrink)

Solving the meta-problem of consciousness requires, among other things, explaining why we are so reluctant to endorse various forms of illusionism about the phenomenal. I will try to tackle this task in two steps. The first consists in clarifying how the concept of consciousness precludes the possibility of any distinction between 'appearance' and 'reality'. The second consists in spelling out our reasons for recognizing the existence of something that satisfies that concept.

This paper develops a philosophical investigation of the merits and faults of a theorem by Lanford , Lanford , Lanford for the problem of the approach towards equilibrium in statistical mechanics. Lanford’s result shows that, under precise initial conditions, the Boltzmann equation can be rigorously derived from the Hamiltonian equations of motion for a hard spheres gas in the Boltzmann-Grad limit, thereby proving the existence of a unique solution of the Boltzmann equation, at least for a very short amount of (...) time. We argue that, by establishing a statistical H-theorem, it offers a prospect to complete Boltzmann’s combinatorial argument, without running against the objections which plug other typicality-based approaches. However, we submit that, while recovering the irreversible approach towards equilibrium for positive times, it fails to predict a monotonic increase of entropy for negative times, and hence it yields the wrong retrodictions about the past evolution of a gas. (shrink)

The aims of my paper are to set out Aquinas’s arguments in favour of the thesis of God as Subsistent Being itself; set out the arguments against; and propose a fresh reading of that thesis that takes into account both Thomistic doctrine and the criticisms of it. In this way, I shall proceed as in a medieval quaestio, with arguments in favour, sed contra and respondeo.

It has been observed that, unlike other kinds of singular judgments, mental self-ascriptions are immune to error through misidentification: they may go wrong, but not as a result of mistaking someone else’s mental states for one’s own. Although recent years have witnessed increasing interest in this phenomenon, three basic questions about it remain without a satisfactory answer: what is exactly an error through misidentification? What does immunity to such errors consist in? And what does it take to explain the fact (...) that mental self-ascriptions exhibit this sort of immunity? The aim of this paper is to bring these questions into focus, propose some tentative answers and use them to show that one prominent attempt to explain the immunity to error through misidentification of mental self-ascriptions is unsuccessful. (shrink)

Kilimanjaro is an example of what some philosophers would call a ‘vague object’: it is only roughly 5895 m tall, its weight is not precise and its boundaries are fuzzy because some particles are neither determinately part of it nor determinately not part of it. It has been suggested that this vagueness arises as a result of semantic indecision: it is because we didn’t make up our mind what the expression “Kilimanjaro” applies to that we can truthfully say such things (...) as “It is indeterminate whether this particle is part of Kilimanjaro”. After reviewing some of the limitations of this approach, I will propose an alternative account, based on a new semantic relation—multiple reference—capable of holding in a one-many pattern between a term and several objects in the domain. I will explain how multiple reference works, what differentiates it from plural reference and how it might be used to accommodate at least some aspects of our ordinary discourse about vague objects. (shrink)

Williamson’s anti-luminosity argument has been thought to be in tension with the doctrine that we enjoy privileged epistemic access to our own mental states. In this paper, I will argue that the tension is only apparent. Friends of privileged access who accept the conclusion of the argument need not give up the claim that our beliefs about our own mental states are mostly or invariably right, nor the view that mental states are epistemically available to us in a way that (...) renders everything within our mind ‘open to view’ – arguably, two main pillars of their doctrine. What they need to reject is the idea that the mental is a realm whose ’determinacy’ or ’fineness of grain’ never escapes our appreciation. This idea – I will suggest – is not essential to privileged access and defenders of the doctrine should not be afraid to give it up. (shrink)

The concept of living has changed in time along the history of biology and its specificity has been associated or to a particular matter, active such as the chemical one, or was considered as a product of the spatial organization of a passive matter. Today, these two paths can be merged in the chemical perspective that takes account of the general reflections on the complexity and on the systemic, in the “systemic complexity” approach.

According to Leibniz’s infinite-analysis account of contingency, any derivative truth is contingent if and only if it does not admit of a finite proof. Following a tradition that goes back at least as far as Bertrand Russell, several interpreters have been tempted to explain this biconditional in terms of two other principles: first, that a derivative truth is contingent if and only if it contains infinitely complex concepts and, second, that a derivative truth contains infinitely complex concepts if and only (...) if it does not admit of a finite proof. A consequence of this interpretation is that Leibniz’s infinite-analysis account of contingency falls prey to Robert Adams’s Problem of Lucky Proof. I will argue that this interpretation is mistaken and that, once it is properly understood how the idea of an infinite proof fits into Leibniz’s circle of modal notions, the problem of lucky proof simply disappears. (shrink)

In der Reihe werden herausragende monographische Untersuchungen und Sammelbände zu allen Aspekten der Philosophie Kants veröffentlicht, ebenso zum systematischen Verhältnis seiner Philosophie zu anderen philosophischen Ansätzen in Geschichte und Gegenwart. Veröffentlicht werden Studien, die einen innovativen Charakter haben und ausdrückliche Desiderate der Forschung erfüllen. Die Publikationen repräsentieren den aktuellsten Stand der Forschung.

This paper presents a lengthy unpublished passage by Russell on the attempts by Pythagoras and subsequent mathematicians to deal with continuity and the logical paradoxes, recently discovered in the manuscript of the _History of Western Philosophy_. In the first part, I provide a short introduction to the new material. In the second, I analyze its philosophical content. In the third, I develop some considerations, mainly in the attempt to solve the following problems: can we determine when and for what purpose (...) Russell wrote these leaves? why were they never published? where do we find similar subjects expounded in the History? where does the significance of the discovery really lie? (shrink)

This paper presents a distinctively metaphysical version of the problem of other minds. The main source of this version of the problem lies in the principle that, when it comes to consciousness, no distinction can sensibly be drawn between appearance and reality. I will argue that, unless we want to call that principle into question, we should seriously consider the possibility of accepting the conclusion that other minds are not like our own. This option is less problematic than it might (...) seem at first if we are willing to reconceive facts of consciousness as subjective rather than objective in nature. -/- . (shrink)

According to Russellian monism (RM), the quiddities which underlie the fundamental causal structure of the physical world are also responsible for the existence of phenomenal consciousness. This view has been argued to provide an attractive alternative to physicalism and dualism, but it is plagued by the so-called ‘combination problem’ – namely, the problem of explaining how the quiddities underlying the microphysical structure of a macroscopic conscious agent (e.g., a human being) combine together to constitute his or her phenomenal experiences. In (...) this paper, I will explore a type of monism that avoids the combination problem altogether. According to this view – which I shall call panquidditist monism – all causal roles, and not just the fundamental ones, stand in need of quiddities realizing them. Moreover, the quiddities that realize causal roles at one physical level should not in general be seen as grounded in, or otherwise derivative on, the quiddities that realize causal roles at lower levels. Crucial to the tenability of this view is a distinction between two varieties of grounding – one aiming to metaphysically explain the causal properties of various objects ‘from below’ (vertical grounding), the other aiming to metaphysically explaining them ‘from the inside’ (horizontal grounding). I will argue that, thanks to the distinction between vertical and horizontal grounds, panquidditist monism is well-placed to secure the advantages that RM promises – but, because of the combination problem, fails to deliver – vis-à-vis physicalism and dualism. (shrink)

The concept of simultaneous masking in visual field is discussed, in the light of classical examples, of the various kinds of the phenomenon, of a modal completion, of the figure/ground phenomenon, of ambiguous and reversible figures, of mimicry and camouflage and eventually of the complexity of the stimulus. There is some reference to masking in auditory field. The “reality” of the masked configuration is discussed, drawing the conclusion that it is perceptually unreal. The fact that the masking phenomenon cannot take (...) place without comparison between two perceptual acts – what we see at one moment and what we see a moment after LATER – and the fact that the masked configuration pops out with some surprise, lead to the conclusion that simultaneous masking in visual field is not a bare perceptual phenomenon, but a psychological process not unlike insight. (shrink)