Performance and control of upright bipedal posture requires a constant and dynamic integration of relative contributions of different sensory inputs (i. e., sensory reweighting) to enable effective adaptations as individuals face environmental changes and perturbations. Children with gymnastic experience showed balance performance closer to that of adults during and after proprioceptive alteration than children without gymnastic experience when their center of pressure (COP) was analyzed. However, a particular COP sway can be achieved through performing and coordinating different postural movements. The (...) aim of this study was to assess how children and adults of different gymnastic experience perform and control postural movements while they have to adjust balance during and after bilateral tendon vibration. All participants were equipped with spherical markers attached to their skin and two vibrators strapped over the Achilles tendons. Bipedal stance was performed in three 45-s trials in two visual conditions (eyes open, EO, and eyes closed, EC) ordered randomly in which vibration lasted 10 s. Posture movements were analyzed by a principal component analysis (PCA) calculated on normalized and weighted markers coordinates. The relative standard deviation of each principal movement component (principal position, PP-rSTD) quantified its contribution to the whole postural movements, i.e., quantified the coordinative structure. The first (principal velocities, PV-rSTD) and second (principal accelerations, PA-rSTD) time-derivatives characterized the rate-dependent sensory information associated with and the neuromuscular control of the postural movements, respectively. Children without gymnastic experience showed a different postural coordinative structure and different sensory-motor control characteristics. They used less ankle movements in the anterior-posterior direction but increased ankle movements in medio-lateral direction, presented larger hip and trunk velocities, and exhibited more hip actions. Gymnastic experience during childhood seemed to benefit the development of proprioceptive reweighting processes in children, leading to a more mature form of coordinating and controlling posture similarly to adults. (shrink)

In _Necropolitics_ Achille Mbembe—a leader in the new wave of Francophone critical theory—theorizes the genealogy of the contemporary world—a world plagued by ever-increasing inequality, militarization, enmity, and terror, as well as by a resurgence of racist, fascist, and nationalist forces determined to exclude and kill. He outlines how democracy has begun to embrace its dark side, or what he calls its “nocturnal body,” which is based on the desires, fears, affects, relations, and violence that drove colonialism. This shift has hollowed (...) out democracy, thereby eroding the very values, rights, and freedoms liberal democracy routinely celebrates. As a result, war has become the sacrament of our times, in a conception of sovereignty that operates by annihilating all those considered to be enemies of the state. Despite his dire diagnosis, Mbembe draws on post-Foucault debates on biopolitics, war, and race, as well as Fanon's notion of care as a shared vulnerability, to explore how new conceptions of the human that transcend humanism might come to pass. These new conceptions would allow us to encounter the Other not as a thing to exclude, but as a person with whom to build a more just world. (shrink)

In _Critique of Black Reason_ eminent critic Achille Mbembe offers a capacious genealogy of the category of Blackness—from the Atlantic slave trade to the present—to critically reevaluate history, racism, and the future of humanity. Mbembe teases out the intellectual consequences of the reality that Europe is no longer the world's center of gravity while mapping the relations among colonialism, slavery, and contemporary financial and extractive capital. Tracing the conjunction of Blackness with the biological fiction of race, he theorizes Black reason (...) as the collection of discourses and practices that equated Blackness with the nonhuman in order to uphold forms of oppression. Mbembe powerfully argues that this equation of Blackness with the nonhuman will serve as the template for all new forms of exclusion. With _Critique of Black Reason_, Mbembe offers nothing less than a map of the world as it has been constituted through colonialism and racial thinking while providing the first glimpses of a more just future. (shrink)

In _Brutalism_, eminent social and critical theorist Achille Mbembe invokes the architectural aesthetic of brutalism to describe our moment, caught up in the pathos of demolition and production on a planetary scale. Just as brutalist architecture creates an affect of overwhelming weight and destruction, Mbembe contends that contemporary capitalism crushes and dominates all spheres of existence. In our digital, technologically focused era, capitalism has produced a becoming-artificial of humanity and the becoming-human of machines. This blurring of the natural and artificial (...) presents a planetary existential threat in which contemporary society’s goal is to precipitate the mutation of the human species into a condition that is at once plastic and synthetic. Mbembe argues that Afro-diasporic thought presents the only solution for breaking the totalizing logic of contemporary capitalism: repairing that which is broken, developing a new planetary consciousness, and reforming a community of humans in solidarity with all living things. (shrink)

What sort of logic do we get if we adopt a supervaluational semantics for vagueness? As it turns out, the answer depends crucially on how the standard notion of validity as truth preservation is recasted. There are several ways of doing that within a supervaluational framework, the main alternative being between “global” construals (e.g., an argument is valid iff it preserves truth-under-all-precisifications) and “local” construals (an argument is valid iff, under all precisifications, it preserves truth). The former alternative is by (...) far more popular, but I argue in favor of the latter, for (i) it does not suffer from a number of serious objections, and (ii) it makes it possible to restore global validity as a defined notion. (shrink)

The U.S. presidential election of 2000 was crucially decided in Florida. And, in Florida, the election hinged crucially on a peculiar sort of question: Does this ballot have a hole? “Yes, it does”, so the ballot is valid and ought to be counted. “No it doesn’t”, and the ballot must be discarded. If only one could tell! Where were the hole experts when we needed them? Eventually the matter was thwarted by the Supreme Court and we all gave up. But (...) we did learn something. We learned that even the destiny of a Presidential Election, if not more, might ultimately depend on one’s criteria for identifying holes—not their material surroundings, which everyone could detect, but the holes themselves. (shrink)

Can we really perceive absences, i.e., missing things? Sartre tells us that when he arrived late for his appointment at the café, he saw the absence of his friend Pierre. Is that really what he saw? Where was it, exactly? Why didn’t Sartre see the absence of other people who were not there? Why did other people who were there not see the absence of Pierre? The perception of absences gives rise to a host of conundrums and is constantly on (...) the verge of conceptual confusion. Here I focus on the need to be clear about four sorts of distinctions: (i) the difference between perceiving an absence and perceiving something that is absent; (ii) the difference between perceiving an absence and an absence of perceiving; (iii) the difference between perceiving an absence and perceiving something as an absence; and (iv) the difference between perceiving an absence and perceiving that something is absent. (shrink)

We tend to talk about (refer to, quantify over) parts in the same way in which we talk about whole objects. Yet a part is not something to be included in an inventory of the world over and above the whole to which it belongs, and a whole is not something to be included in the inventory over and above its constituent parts. This paper is an attempt to clarify a way of dealing with this tension which may be labeled (...) the Minimalist View: An element in the field of a part-whole relation is to be included in an inventory of the world if and only if it does not overlap any distinct element that is itself included in the inventory. (shrink)

L’Afrique a participé jusqu’a présent, souvent à titre de laboratoire, au développement de la science occidentale. Les défis rencontrés par la théorie critique aujourd’hui sont l’instrumentalisation de la théorie par les gouvernements, la prolifération de pratiques critiques diverses, notamment écologique, et surtout l’émergence d’un capitalisme de l’image et de l’affect. C’est en relation avec la Chine que l’Afrique peut apporter de nouvelles réponses et relever ces défis.

Are there any bona fide boundaries, i.e., boundaries that carve at the joints? Or is any boundary —hence any object—the result of a fiat articulation reflecting our cognitive biases and our so-cial practices and conventions? Does the choice between these two options amount to a choice between realism and wholesome relativism?

According to a certain familiar way of dividing up the business of philosophy, ontology is concerned with the question of what entities exist (a task that is often identified with that of drafting a “complete inventory” of the universe) whereas metaphysics seeks to explain, of those entities, what they are (i.e., to specify the “ultimate nature” of the items included in the inventory). This distinction carries with it a natural thought, namely, that ontology is in some way prior to metaphysics. (...) One must first of all figure out what things exist (or might exist); then one can attend to the further question of what they are, specify their nature, speculate on those features that make each thing the thing it is. I sympathize with that thought, but there is a major worry lurking in the background and there are several complications that emerge in the foreground. The purpose of this paper is to address such worries and complications and to come up with a plausible way of understanding the “priority thesis” that makes it both reasonable and, hopefully, useful. (shrink)

That parthood is a transitive relation is among the most basic principles of classical mereology. Alas, it is also very controversial. In a recent paper, Ingvar Johansson has put forward a novel diagnosis of the problem, along with a corresponding solution. The diagnosis is on the right track, I argue, but the solution is misleading. And once the pieces are properly put together, we end up with a reinforcement of the standard defense of transitivity on behalf of classical mereology.

David Lewis has argued that impossible worlds are nonsense: if there were such worlds, one would have to distinguish between the truths about their contradictory goings-on and contradictory falsehoods about them; and this--Lewis argues--is preposterous. In this paper I examine a way of resisting this argument by giving up the assumption that ‘in so-and-so world’ is a restricting modifier which passes through the truth-functional connectives The outcome is a sort of subvaluational semantics which makes a contradiction ‘A & ~A’ false (...) even when both ‘A’ and ‘~A’ are true, just as supervaluational semantics makes a tautology ‘A v ~A’ true even when neither ‘A’ nor ‘~A’ are. Connections with discussive logics and complications of the account are discussed, and some general morals are drawn. (shrink)

Standard lore has it that a proper name is a temporally rigid designator. It picks out the same entity at every time at which it picks out an entity at all. If the entity in question is an enduring continuant then we know what this means, though we are also stuck with a host of metaphysical puzzles concerning endurance itself. If the entity in question is a perdurant then the rigidity claim is trivial, though one is left wondering how it (...) is that different speakers ever manage to pick out one and the same entity when a host of suitable, overlapping candidates are available. But what if the entity in question is neither a continuant nor a perdurant? What if the things we talk about in ordinary language are time-bound entities that cannot truly be said to persist through time, or stage sequences whose unity resides exclusively in our minds--like the “waves” at the stadium or the characters of a cartoon? In such cases the rigidity claim can’t be right and a counterpart-theoretic semantics seems required. Is that bad? I say it isn’t. And it had better not be, if that turns out to be the best metaphysical option we have. (shrink)

I endorse Composition as Identity, broadly and loosely understood as the thesis that a composite whole is nothing over and above its parts, and the parts nothing over and above the whole. Thus, given an object, x, composed of n proper parts, y1, ..., yn, I feel the tension between my Quinean heart and its Lewisian counterpart. I feel the tension between my obligation to countenance n+1 things, x and the y’s, each of which is a distinct portion of reality, (...) and my inclination to count just 1 thing, x, or just n things, the y’s, the former encompassing the same amount of reality as the latter. This paper is an attempt to reconstruct this tension and to explain it away without forgoing the intimate link between counting and countenancing. (shrink)

Abstract. As a general theory of reasoning—and as a general theory of what holds true under every possible circumstance—logic is supposed to be ontologically neutral. It ought to have nothing to do with questions concerning what there is, or whether there is anything at all. It is for this reason that traditional Aristotelian logic, with its tacit existential presuppositions, was eventually deemed inadequate as a canon of pure logic. And it is for this reason that modern quantification theory, too, with (...) its residue of existentially loaded theorems and patterns of inference, has been claimed to suffer from a defect of logical purity. The law of non-contradiction rules out certain circumstances as impossible—circumstances in which a statement is both true and false, or perhaps circumstances where something both is and is not the case. Is this to be regarded as a further ontological bias? (shrink)

[ES] Aquí articulo y luego defiendo las dos afirmaciones siguientes: que es un error pensar que la estructura del mundo debe reflejar la estructura de las teorías por las cuales lo representamos, y por medio de las cuales tratamos de descifrarlo, simplemente porque estas teorías parecen funcionar; entre las consecuencias más lamentables de este error está la tendencia generalizada a pensar que debe haber una pluralidad de realidades, o varios niveles diferentes e irreductibles de una realidad estratificada, simplemente porque nuestro (...) credo incluye una pluralidad de teorías cada una de las cuales aparenta ser tan importante y confiable como es irreductible a las demás. [EN] I articulate and then defend the following two claims: it is a mistake to think that the structure of the world should mirror the structure of the theories by which we represent it, and through which we try to decipher it, simply because those theories appear to work; among the most deplorable consequences of this mistake is the widespread tendency to think that there must be a plurality of realities, or several different and irreducible levels of a stratified reality, merely because our credo includes a plurality of theories each of which appears to be as important and trustworthy as it is irreducible to the others. (shrink)

One logic or many? I say—many. Or rather, I say there is one logic for each way of specifying the class of all possible circumstances, or models, i.e., all ways of interpreting a given language. But because there is no unique way of doing this, I say there is no unique logic except in a relative sense. Indeed, given any two competing logical theories T1 and T2 (in the same language) one could always consider their common core, T, and settle (...) on that theory. So, given any language L, one could settle on the minimal logic T0 corresponding to the common core shared by all competitors. That would be a way of resisting relativism, as long as one is willing to redraw the bounds of logic accordingly. However, such a minimal theory T0 may be empty if the syntax of L contains no special ingredients the interpretation of which is independent of the specification of the relevant L-models. And generally—I argue—this is indeed the case. (shrink)

A lot of work in metaphysics relies on linguistic analysis and intuitions. Do we want to know what sort of things there are or could be? Then let’s see what sort of things there must be in order for what we truthfully say to be true. Do we want to see whether x is distinct from y? Then let’s see whether there is any statement that is true of x but not of y. And so on. In this paper I (...) argue that this way of proceeding is full of traps and is bound to be pretty useless unless we already have a good idea of what sort of things there are, and of how we are going to count them. (shrink)

Jeffery et al. suggest that three-dimensional environments are not represented according to their volumetric properties, but in a quasi-planar fashion. Here we take into consideration the role of visual experience and the use of technology for spatial learning to better understand the nature of the preference of horizontal over vertical spatial representation.

Remember the story of the most-most? It’s the story of that club in New York where people are the most of every type. There is the hairiest bald man and the baldest hairy man; the shortest giant and the tallest dwarf; the smartest idiot and the stupidest wise man. They are all there, including honest thieves and crippled acrobats. On Saturday night they have a party, eat, drink, dance. Then they have a contest. “And if you can tell the hairiest (...) bald man from the baldest hairy man—we are told—you get a prize.”. (shrink)

Like the journal TOPOl, the TOPOl Library is based on the assumption that philosophy is a lively, provocative, delightful activity, which constantly challenges our inherited habits, painstakingly elaborates on how things could be different, in other stories, in counterfactual situations, in alternative possible worlds. Whatever its ideology, whether with the intent of uncovering a truer structure of reality or of shooting our anxiety, of exposing myths or of following them through, the outcome of philosophical activity is always the destabilizing, unsettling (...) generation of doubts, of objections, of criticisms. It follows that this activity is intrinsically a dialogue, that philosophy is first and foremost philosophical discussion, that it requires bringing out conflicting points of view, paying careful, sympathetic attention to their structure, and using this dialectic to articulate one's approach, to make it richer, more thoughtful, more open to variation and play. And it follows that the spirit which one brings to this activity must be one of tolerance, of always suspecting one's own blindness and consequently looking with unbiased eye in every comer, without fearing to pass a (fallible) judgment on what is there but also without failing to show interest and respect. (shrink)

Some philosophers have argued that the vagueness exhibited by names and descriptions such as ‘Mount Everest’, ‘Downtown Manhattan’, or ‘that cloud in the sky’ is ultimately ontological: they are vague because they refer to vague objects, objects with fuzzy boundaries. I take the opposite stand and argue for the view that all vagueness is semantic. There is no such thing as a vague mountain. Rather, there are many things where we conceive the mountain to be, each with its precise boundary, (...) and when we say ‘Everest’ we are just being vague as to which thing we are referring to. This paper defends this view against some plausible objections. (shrink)

I focus on three mereological principles: the Extensionality of Parthood (EP), the Uniqueness of Composition (UC), and the Extensionality of Composition (EC). These principles are not equivalent. Nonetheless, they are closely related (and often equated) as they all reflect the basic nominalistic dictum, No difference without a difference maker. And each one of them—individually or collectively—has been challenged on philosophical grounds. In the first part I argue that such challenges do not quite threaten EP insofar as they are either self-defeating (...) or unsupported. In the second part I argue that they hardly undermine the tenability of EC and UC as well. (shrink)

There are two ways of understanding the notion of a contradiction: as a conjunction of a statement and its negation, or as a pair of statements one of which is the negation of the other. Correspondingly, there are two ways of understanding the Law of Non-Contradiction (LNC), i.e., the law that says that no contradictions can be true. In this paper I offer some arguments to the effect that on the first (collective) reading LNC is non-negotiable, but on the second (...) (distributive) reading it is perfectly plausible to suppose that LNC may, in some rather special and perhaps undesirable circumstances, fail to hold. (shrink)

There are two main ways, philosophically, of characterizing the business of ontology. On one account, made popular by Quine, ontology is concerned with the material question of what there is. On the other, which made its way into our times through Brentano and his pupils, ontology is concerned with the task of laying bare the formal structure of all there is, whatever it is. My question, here, is whether one can pursue one sort of theory without also engaging in the (...) other—whether, or to what extent, the tasks of material ontology presuppose the backing of some formal-ontological theory, and whether or to what extent formal ontology can be, in the material sense of the term, ontologically neutral. (shrink)

Ontology has come to gain huge currency in the information sciences, with techniques, applications, and results vastly exceeding the traditional concerns of philosophy. How did that happen? Where are we heading to? I do not have the answers. But I know what it took and what is needed. It took—and we need—the skills of a good Carnapian engineer, someone capable and willing to build bridges across fields even though each side regards them as a troublesome intruder.

An overview of the origins and development of analytic metaphysics. The first part is strictly historical, focusing mainly on Russell and Moore, and then on Wittgenstein, Carnap, and Stebbing, but also on other authors whose work has been more or less directly influential, from Husserl to Twardowski, Kotarbiński, and Leśniewski. The second part deals with later developments, including recent work in ontology and meta-ontology, identity, persistence through time, and the metaphysics of modality.

Mereotopology is today regarded as a major tool for ontological analysis, and for many good reasons. There are, however, a number of open questions that call for an answer. Some are philosophical, others have direct applicative import, but all are crucial for a proper assessment of the strengths and limits of mereotopology. This paper is an attempt to put sum order in this area.

I argue that the conjunction of perdurantism (the view that objects are temporally extended) and universalism (the thesis that any old class of things has a mereological fusion) gives rise to undesired complications when combined with certain plausible assumptions concerning the semantics of tensed statements.

We offer a critical overview of two sorts of proof systems that may be said to characterize classical propositional logic indirectly (and non-standardly): refutation systems, which prove sound and complete with respect to classical contradictions, and rejection systems, which prove sound and complete with respect to the larger set of all classical non-tautologies. Systems of the latter sort are especially interesting, as they show that classical propositional logic can be given a paraconsistent characterization. In both cases, we consider Hilbert-style systems (...) as well as Gentzen-style sequent calculi and natural-deduction formalisms. (shrink)

Paul Hovda’s excellent paper ‘What Is Classical Mereology?' has fruitfully reshaped the debate concerning the axiomatic foundations of classical mereology. Precisely because of the importance of Hovda’s work and its usefulness as a reference tool, we note here that one of the five axiom systems presented therein, corresponding the ‘Third Way’ to classical mereology, is defective and must be amended. In addition, we note that two other axiom systems, corresponding to the ‘First Way’ and to the ‘Fifth Way’, involve redundancies.

In previous work I have argued that talk about negative events should not be taken at face value: typically, what we are inclined to think of as a negative event (John’s failure to go jogging) is just an ordinary, positive event (his going to the movie instead); it is a positive event under a negative description. Here I consider more closely the difficulties that arise in those cases where no positive event seems available to do the job, as with putative (...) cases of causation by omission. In particular, I elaborate on Helen Beebee’s idea that not all causal explanations are reports of causation. When we mention John’s failure to turn off the gas as an explanans of why there was an explosion, we do not say what caused the explosion. We do not mention any of the relevant causes. We just remark that one sort of event that was supposed to occur, and whose occurrence would have prevented the explosion, did not in fact occur. (shrink)