Two Temporal Logics of Contingency

This work concerns the use of operators for past and future con-tingency in Priorean temporal logic. We will develop a system namedCt, whose language includes a propositional constant and prove that(i) Ct is complete with respect to a certain class of general frames and(ii) the usual operators for past and future necessity are denable insuch system. Furthermore, we will introduce the extension Ctlin thatcan be interpreted on linear and transitive general frames. The theo-retical result of the current work is that contingency can be treatedas a primitive notion in reasoning about temporal modalities

A Realistic View on Normative Conflicts

Kulicki and Trypuz (2016) introduced three systems of multi-valued deontic action logic to handle normative conflicts. The first system suggests a pessimistic view on normative conflicts, according to which any conflicting option represents something forbidden; the second system suggests an optimistic view, according to which any conflicting option represents something obligatory; finally, the third system suggests a neutral view, according to which any conflicting option represents something that is neither obligatory nor forbidden. The aim of the present paper is to propose a fourth system in this family, which comes with a realistic view on normative conflicts: a normative conflict remains unsolved unless it is generated by two or more normative sources that can be compared. In accordance with this, we will provide a more refined formal framework for the family of systems at issue, which allows for explicit reference to sources of norms. Conflict resolution is thus a consequence of a codified hierarchy of normative sources

Alternative Semantics for Normative Reasoning with an Application to Regret and Responsibility

We provide a fine-grained analysis of notions of regret and responsibility (such as agent-regret and individual responsibility) in terms of a language of multimodal logic. This language undergoes a detailed semantic analysis via two sorts of models: (i) relating models, which are equipped with a relation of propositional pertinence, and (ii) synonymy models, which are equipped with a relation of propositional synonymy. We specify a class of strictly relating models and show that each synonymy model can be transformed into an equivalent strictly relating model. Moreover, we define an axiomatic system that captures the notion of validity in the class of all strictly relating models

Verità e giustificazione degli asserti temporali

Il rapporto tra verità e temporalità, discusso dai pensatori antichi e medievali, è tornato centrale nell’indagine logica solo negli ultimi decenni, dopo essere stato a lungo eclissato dalla volontà di "detemporalizzare" lo studio del ragionamento formale. In queste pagine cercheremo di analizzare alcuni aspetti logici e filosofici della questione, organizzando il lavoro in tre parti. La prima parte è dedicata al trattamento di elementari nozioni di tempo nei sistemi formali, con particolare attenzione per le proposte avanzate alla metà del secolo scorso da Arthur Norman Prior. La seconda parte riguarda alcuni problemi dovuti all’uso di una semantica bivalente per gli asserti temporali: l’esigenza di chiarificare la teoria corrispondentista della verità e il superamento dello scoglio del determinismo. Nella terza parte, infine, ci concentreremo su approcci semantici alternativi: le logiche a più valori (Łukasiewicz, Prior), il metodo delle supervalutazioni (Thomason, Van Fraassen) e le idee giustificazioniste (Dummett). Vedremo che questi approcci forniscono spunti interessanti per un trattamento unitario delle nozioni temporali e modali

Two Temporal Logics of Contingency

This work concerns the use of operators for past and future con-tingency in Priorean temporal logic. We will develop a system namedCt, whose language includes a propositional constant and prove that(i) Ct is complete with respect to a certain class of general frames and(ii) the usual operators for past and future necessity are denable insuch system. Furthermore, we will introduce the extension Ctlin thatcan be interpreted on linear and transitive general frames. The theo-retical result of the current work is that contingency can be treatedas a primitive notion in reasoning about temporal modalities

The Good, the Bad and the Right: Formal Reductions among Deontic Concepts

The present article provides a taxonomic analysis of bimodal logics of normative ideality and normative awfulness, two notions whose meaning is here explained in terms of the moral values pursued by a given community. Furthermore, the article addresses the traditional problem of a reduction among deontic concepts: we explore the possibility of defining other relevant normative notions, such as obligation, explicit permission and Hohfeldian relations, in terms of ideality and awfulness. Some proposals in this respect, which have been formulated in the literature over the years, are here improved and discussed with reference to the various logics that we will introduce

Postural adjustments to self-triggered perturbations under conditions of changes in body orientation

We studied anticipatory and compensatory postural adjustments (APAs and CPAs) associated with self-triggered postural perturbations in conditions with changes in the initial body orientation. In particular, we were testing hypotheses on adjustments in the reciprocal and coactivation commands, role of proximal vs. distal muscles, and correlations between changes in indices of APAs and CPAs. Healthy young participants stood on a board with full support or reduced support area and held a standard load in the extended arms. They released the load in a self-paced manned with a standard small-amplitude arm movement. Electromyograms of 12 muscles were recorded and used to compute reciprocal and coactivation indices between three muscle pairs on both sides of the body. The subject's body was oriented toward one of three targets: straight ahead, 60° to the left, and 60° to the right. Body orientation has stronger effects on proximal muscle pairs compared to distal muscles. It led to more consistent changes in the reciprocal command compared to the coactivation command. Indices of APAs and CPAs showed positive correlations across conditions. We conclude that the earlier suggested hierarchical relations between the reciprocal and coactivation command could be task-specific. Predominance of negative or positive correlations between APA and CPA indices could also be task-specific

Transcranial direct current stimulation improves the QT variability index and autonomic cardiac control in healthy subjects older than 60 years

Background: Noninvasive brain stimulation technique is an interesting tool to investigate the causal relation between cortical functioning and autonomic nervous system (ANS) responses. Objective: The objective of this report is to evaluate whether anodal transcranial direct current stimulation (tDCS) over the temporal cortex influences short-period temporal ventricular repolarization dispersion and cardiovascular ANS control in elderly subjects. Subjects and methods: In 50 healthy subjects (29 subjects younger than 60 years and 21 subjects older than 60 years) matched for gender, short-period RR and systolic blood pressure spectral variability, QT variability index (QTVI), and noninvasive hemodynamic data were obtained during anodal tDCS or sham stimulation. Results: In the older group, the QTVI, low-frequency (LF) power expressed in normalized units, the ratio between LF and high-frequency (HF) power, and systemic peripheral resistances decreased, whereas HF power expressed in normalized units and α HF power increased during the active compared to the sham condition (P,0.05). Conclusion: In healthy subjects older than 60 years, tDCS elicits cardiovascular and autonomic changes. Particularly, it improves temporal ventricular repolarization dispersion, reduces sinus sympathetic activity and systemic peripheral resistance, and increases vagal sinus activity and baroreflex sensitivity