We give examples of calculi that extend Gentzen’s sequent calculusLKby unsound quantifier inferences in such a way that derivations lead only to true sequents, and proofs therein are nonelementarily shorter thanLK-proofs.

We prove a number of results on the determinacy of σ-projective sets of reals, i.e., those belonging to the smallest pointclass containing the open sets and closed under complements, countable unions, and projections. We first prove the equivalence between σ-projective determinacy and the determinacy of certain classes of games of variable length <ω^2 (Theorem 2.4). We then give an elementary proof of the determinacy of σ-projective sets from optimal large-cardinal hypotheses (Theorem 4.4). Finally, we show how to generalize the proof (...) to obtain proofs of the determinacy of σ-projective games of a given countable length and of games with payoff in the smallest σ-algebra containing the projective sets, from corresponding assumptions (Theorem 5.1, Theorem 5.4). (shrink)

We prove a topological completeness theorem for the modal logic $$\textsf{GLP}$$ GLP containing operators $$\{\langle \xi \rangle :\xi \in \textsf{Ord}\}$$ { ⟨ ξ ⟩ : ξ ∈ Ord } intended to capture a wellordered sequence of consistency operators increasing in strength. More specifically, we prove that, given a tall-enough scattered space X, any sentence $$\phi $$ ϕ consistent with $$\textsf{GLP}$$ GLP can be satisfied on a polytopological space based on finitely many Icard topologies constructed over X and corresponding to the (...) finitely many modalities that occur in $$\phi $$ ϕ. (shrink)

For every countable wellordering $\alpha $ greater than $\omega $, it is shown that clopen determinacy for games of length $\alpha $ with moves in $\mathbb {N}$ is equivalent to determinacy for a class of shorter games, but with more complicated payoff. In particular, it is shown that clopen determinacy for games of length $\omega ^2$ is equivalent to $\sigma $ -projective determinacy for games of length $\omega $ and that clopen determinacy for games of length $\omega ^3$ is equivalent (...) to determinacy for games of length $\omega ^2$ in the smallest $\sigma $ -algebra on $\mathbb {R}$ containing all open sets and closed under the real game quantifier. (shrink)

This paper examined the relationship between coaches and youth athletes in China by comparing data collected before and after the lockdown. A total of 221 youth athletes aged 13-19 years in one professional football school completed coach-athlete relationship questionnaires. The rank-sum test was used to verify the differences in the data. The results of the Mann-Whitney U test showed that the mean value of the three dimensions of the coach-athlete relationship (closeness, commitment, and complementarity) increased after the COVID-19 lockdown. The (...) results also showed that athletes of different age categories showed different changes in the coach-athlete relationship after the lockdown, and the changes were not significantly related to the severity of the COVID-19 epidemic. The theoretical and practical implications are discussed. (shrink)

Francisco de Goya y Lucientes (1746–1828) manifeste dans les 82 gravures de la série Les désastres de la guerre, réalisées entre 1810 et 1815, un cri de protestation contre la violence du soulèvement du Dos de Mayo suite à l’invasion des troupes napoléoniennes, la guerre d'indépendance espagnole (1808–1814) et la Restauration bourbonienne qui s'ensuivit en 1814. Mais au lieu de développer une vision héroïque de la guerre Goya y représente la force des oppositions en prise avec la bestialité et brosse (...) un paysage humain qui mêle le sublime et l’horreur mais aussi des harmonies funèbres qui jouent avec les hommes emportés par l’Histoire. (shrink)

Typically, existentialist analyses of “America” have been limited to North America (more specifically, the United States). I argue that developing an adequate framework for existentially analyzing America requires a turn to Mexican existentialism. In Emilio Uranga’s and Jorge Portilla’s writings, we discover new conceptual tools for understanding Americanness as such. These thinkers help us imagine an account of American being that does not restrict itself to the United States by using the concepts of existentialism to describe the crises their neighbors (...) to the north as well as they themselves face. American existence has been historically characterized by a convergence (oftentimes clash) of disparate races, ethnicities, languages, cultures, religions, and identities. As history unfolded, this convergence led to various existential crises across the Americas. Whereas the US American way of life is marred by a blustering, naïve, and purposeless misuse of freedom that disregards the other, the existential crisis the Mexican lives is characterized by “accidentality” and “zozobra.” Despite these important differences, all existentialists, and the Mexican existentialists of the Hyperion Group especially, remind us that there is a common way to overcome the various existential crises plaguing the Americas, and that is to exercise freedom in a purposeful, communally conscious manner. (shrink)

Let Mn♯ denote the minimal active iterable extender model which has n Woodin cardinals and contains all reals, if it exists, in which case we denote by Mn the class-sized model obtained by iterating the topmost measure of Mn class-many times. We characterize the sets of reals which are Σ1-definable from R over Mn, under the assumption that projective games on reals are determined:1. for even n, Σ1Mn=⅁RΠn+11;2. for odd n, Σ1Mn=⅁RΣn+11.This generalizes a theorem of Martin and Steel for L, (...) that is, the case n=0. As consequences of the proof, we see that determinacy of all projective games with moves in R is equivalent to the statement that Mn♯ exists for all n∈N, and that determinacy of all projective games of length ω2 with moves in N is equivalent to the statement that Mn♯ exists and satisfies AD for all n∈N. (shrink)

Loyalty is a much-discussed topic among business ethicists, but this discussion seems to have issued in very few clear conclusions. This article builds on the existing literature on the subject and attempts to ground a definite conclusion on a limited topic: whether, and under what conditions, it makes sense for an employee to offer loyalty to his employer. The main ways in which loyalty to one’s employer can contribute to human flourishing are that it makes the employee more trustworthy and (...) therefore more valuable as an employee; makes it easier to form authentic relationships in other areas of the employee’s life; expands the employee’s field of interests and gives her or him a richer identity; provides greater motivation for the employee’s work; makes it possible to have a greater unity in the employee’s life; improves the performance of the organization for which the employee works; contributes to the protection of valuable social institutions; and, in so far as many employees share an attitude of loyalty towards the organization which employs them, it becomes possible for this organization to become a true community. Last, but not the least, loyal relationships have an inherent value. The article also reviews the main arguments that have been offered against employee loyalty and concludes that none of them offers a reason why it would be inappropriate in all cases for an employee to be loyal to her or his employer. The force of these arguments depends on the specific attributes of the organization for which the employee works. The main conclusion of the article is that while being a loyal employee involves risk, it has the potential to contribute significantly to the employee’s fulfilment. The main challenge for employees is to identify employers who are worthy of being loyal to. (shrink)

El siguiente trabajo analiza las acciones artísticas ligadas al Colectivo Escena Política que tuvieron lugar en la ciudad de Buenos Aires entre 2013 y 2016. Daremos cuenta de tres formas específicas de intervención artístico-política en el espacio público. La primera relacionada con una denuncia de la explotación laboral de los artistas escénicos en la ciudad. La segunda vinculada a prácticas micropolíticas que denominamos activismo de lo sensible. Y la tercera, relacionada con la lucha llevada adelante por la Asamblea Lopérfido Renunciá (...) Ya, en conjunto con organismos de derechos humanos. En última instancia, el artículo propone que la eficacia política del activismo artístico depende de su articulación sincrónica con las diversas luchas que atraviesan el entramado social. (shrink)

This paper introduces the theory QST of quasets as a formal basis for the Nmatrices. The main aim is to construct a system of Nmatrices by substituting standard sets by quasets. Since QST is a conservative extension of ZFA (the Zermelo-Fraenkel set theory with Atoms), it is possible to obtain generalized Nmatrices (Q-Nmatrices). Since the original formulation of QST is not completely adequate for the developments we advance here, some possible amendments to the theory are also considered. One of the (...) most interesting traits of such an extension is the existence of complementary quasets which admit elements with undetermined membership. Such elements can be interpreted as quantum systems in superposed states. We also present a relationship of QST with the theory of Rough Sets RST, which grants the existence of models for SQT formed by rough sets. Some consequences of the given formalism for the relation of logical consequence are also analysed. (shrink)

There is considerable evidence that the experience of justice is associated with perceived legitimacy of authority, but there has been no research about this association when considering past rather than current fairness. Based on the fairness heuristic theory, we tested the hypothesis that interpersonal justice trajectories positively affect perceived legitimacy of the authority; we also tested whether social class moderated this effect. Community residents rated the authority's fairness on 16 consecutive weeks and rated perceived legitimacy on the 16th week. The (...) results of latent growth modeling showed that the trajectory of interpersonal justice scores leading up to the final week significantly predicted perceived legitimacy, regardless of the current experience of interpersonal fairness. Tests of moderation showed that the legitimacy perceptions of individuals of lower subjective social class were significantly affected by interpersonal justice trajectories, whereas this was not the case among individuals of higher subjective social class. The results are discussed in terms of their implications for research on perceived legitimacy and justice, as well as their implications for understanding social class. (shrink)

El problema de la libertad es uno de los más áridos de la filosofía. Paul Ricoeur intenta reconstruir el problema tomando el eje del análisis: la naturaleza dicotómica de los discursos sostenidos sobre la cuestión. De un lado, tenemos la “perspectiva de la tercera persona”. Desde esta mirada, cada acto que realizamos está causalmente determinada. Por el otro lado, tenemos la “perspectiva de la tercera persona”, en la que todas nuestras acciones libres parecieran brotar del “yo”. El problema comienza cuando (...) intentamos reconciliar ambas perspectivas. Este trabajo revisará algunos de los argumentos presentados por ambos lados, y el posicionamiento de Ricoeur en el debate. (shrink)