This article proposes the use of temporal logic for an analysis of instrumentality inspired by the work of G.H. von Wright. The first part of the article contains the philosophical foundations. We discuss von Wright’s general theory of agency and his account of instrumentality. Moreover, we propose several refinements to this framework via rigorous definitions of the core notions involved. In the second part, we develop a logical system called Temporal Logic of Action and Expectations (TLAE). The logic is inspired (...) by a fragment of propositional dynamic logic based on indeterministic time. The system is proven to be weakly complete relative to its given semantics. We then employ TLAE to formalise and analyse the instrumentality relations defined in the first part of the paper. Last, we point out philosophical implications and possible extensions of our work. (shrink)

STIT logic is a prominent framework for the analysis of multi-agent choice-making. In the available deontic extensions of STIT, the principle of Ought-implies-Can (OiC) fulfills a central role. However, in the philosophical literature a variety of alternative OiC interpretations have been proposed and discussed. This paper provides a modular framework for deontic STIT that accounts for a multitude of OiC readings. In particular, we discuss, compare, and formalize ten such readings. We provide sound and complete sequent-style calculi for all of (...) the various STIT logics accommodating these OiC principles. We formally analyze the resulting logics and discuss how the different OiC principles are logically related. In particular, we propose an endorsement principle describing which OiC readings logically commit one to other OiC readings. (shrink)

This work provides proof-search algorithms and automated counter-model extraction for a class of STIT logics. With this, we answer an open problem concerning syntactic decision procedures and cut-free calculi for STIT logics. A new class of cut-free complete labelled sequent calculi G3LdmL^m_n, for multi-agent STIT with at most n-many choices, is introduced. We refine the calculi G3LdmL^m_n through the use of propagation rules and demonstrate the admissibility of their structural rules, resulting in auxiliary calculi Ldm^m_nL. In the single-agent case, we (...) show that the refined calculi Ldm^m_nL derive theorems within a restricted class of (forestlike) sequents, allowing us to provide proof-search algorithms that decide single-agent STIT logics. We prove that the proof-search algorithms are correct and terminate. (shrink)

We present cut-free labelled sequent calculi for a central formalism in logics of agency: STIT logics with temporal operators. These include sequent systems for Ldm , Tstit and Xstit. All calculi presented possess essential structural properties such as contraction- and cut-admissibility. The labelled calculi G3Ldm and G3Tstit are shown sound and complete relative to irreflexive temporal frames. Additionally, we extend current results by showing that also Xstit can be characterized through relational frames, omitting the use of BT+AC frames.

In this work we answer a long standing request for temporal embeddings of deontic STIT logics by introducing the multi-agent STIT logic TDS . The logic is based upon atemporal utilitarian STIT logic. Yet, the logic presented here will be neutral: instead of committing ourselves to utilitarian theories, we prove the logic TDS sound and complete with respect to relational frames not employing any utilitarian function. We demonstrate how these neutral frames can be transformed into utilitarian temporal frames, while preserving (...) validity. Last, we discuss problems that arise from employing binary utility functions in a temporal setting. (shrink)

This paper examines the conceptual and terminological overlap between theories and models of practical deliberation developed within the fields of Practical Reasoning (PR) and Practical Argumentation (PA). It carefully delineates the volitional, epistemic, normative, and social commitments invoked and explicates various rationales for attributing the label ‘practical’ to instances of reasoning and argumentation. Based on these analyses, the paper develops a new approach to practical deliberation called the Stakeholder Commitment Approach (SCA). By distinguishing between ‘problem holder’ and ‘problem solver’, and (...) specifying the distributions of attributable commitments among the stakeholders, the SCA introduces an extension and refinement of the grounds for assigning the label ‘practical’ that brings PR and PA closer together. (shrink)

Centered around the analysis of the prescriptive portion of the Vedas, the Sanskrit philosophical school of Mīmāṃsā provides a treasure trove of normative investigations. We focus on the leading Mīmāṃsā authors Prabhākara, Kumārila and Maṇḍana, and discuss three modal logics that formalize their deontic theories. In the first part of this paper, we use logic to analyze, compare and clarify the various solutions to the _śyena_ controversy, a two-thousand-year-old problem arising from seemingly conflicting commands in the Vedas. In the second (...) part, the formalized Mīmāṃsā theories are analyzed and employed to provide alternative perspectives on well-known paradoxes from the contemporary field of deontic logic. Thus, we go from logic to Mīmāṃsā and back again. (shrink)

We formally introduce a novel, yet ubiquitous, category of norms: norms of instrumentality. Norms of this category describe which actions are obligatory, or prohibited, as instruments for certain purposes. We propose the Logic of Agency and Norms (LAN) that enables reasoning about actions, instrumentality, and normative principles in a multi-agent setting. Leveraging LAN , we formalize norms of instrumentality and compare them to two prevalent norm categories: norms to be and norms to do. Last, we pose principles relating the three (...) categories and evaluate their validity vis-à-vis notions of deliberative acting. On a technical note, the logic will be shown decidable via the finite model property. (shrink)

Het denken van de Nederlandse filosoof Leo Polak (1880-1941) heeft nog altijd niet aan actualiteit ingeboet. Hij bepleitte hartstochtelijk de autonomie van de menselijke rede, worstelde met de grondslag van onze ethiek en wierp zich in een tijd van politieke massabewegingen en toenemende verzuiling op als kampioen van het vrije denken. Zelfs tijdens de Duitse bezetting hield hij vast aan zijn zelfstandig oordeel – een houding die hij eind 1941 met de dood in een concentratiekamp moest bekopen. Al die jaren (...) hield hij een dagboek bij, voor hem een essentieel middel om greep te krijgen op zijn leven. Op basis hiervan worden in deze bundel nieuwe aspecten van Polaks leven en werk belicht: zijn denken over schuld en vergelding, zijn verhouding tot grote filosofen als Spinoza en Heymans en zijn houding tegenover het nationaalsocialisme, maar ook zijn familieleven, zijn boekenverzameling en zijn geestelijke nalatenschap. (shrink)

Historians of science and the philosophy of science find the substance and stance of Isaac Beeckman's thought highly interesting, for it represented an early attempt to develop a comprehensive picture of the world by means of mechanistic theory, that is, forces acting upon one another. Besides possibly influencing Descartes, this view broke away from medieval religious assumptions and belief in occult forces. Berkel teases out Beeckman's evolving approach to nature by means of his extensive journals, explaining the leading concept (...) of "picturability." Beeckman supplied a stepping stone (one still not widely appreciated) on the path that led to the scientific revolution. (shrink)

We present a logic of agency called LAE whose language includes propositional constants for actions and expectations. The logic is based on Von Wright’s theory of agency in general and his analysis of instrumentality in particular. An axiomatization of the logic, including an independence of agents axiom, is provided and soundness and completeness are shown with respect to its intended class of frames. The framework of LAE will allow us to formally define a manifold of concepts involved in agency theories, (...) including Von Wright’s four elementary forms of action, the notion of forbearance and notions of instrumentality that make reference to an agent’s expectations. (shrink)

From 22-25 May, 1999, the University of Groningen hosted an international conference on 'The Book of Nature. Continuity and change in European and American attitudes towards the natural world'. From Antiquity down to our own time, theologians, philosophers and scientists have often compared nature to a book, which might, under the right circumstances, be read and interpreted in order to come closer to the 'Author' of nature, God. The 'reading' of this book was not regarded as mere idle curiosity, but (...) it was seen as leading to a deeper understanding of God's wisdom and power, and it culturally legitimated and promoted a positive attitude towards nature and its study. A selection of the papers which were delivered at the conference has been edited in two volumes. The first deals with the perception of the Book of Nature in Antiquity and the Middle Ages; the second volume is devoted to the history of the concept in early modern and modern history. (shrink)

Ibn al-Sāʿī, Consorts of the Caliphs: Women and the Court of Baghdad. Edited by Shawkat M. Toorawa, translated by Editors of LAL. Library of Arabic Literature. New York: New York University Press, 2015. Pp. xlv + 226. $30.

The contribution of data use in schools has been proven via visible changes in policy and practice in schools, changes in practitioners learning or cognition and changes in opinions or attitudes regarding teaching or policy-making. Nevertheless, limited research is available on the extent to which data use in schools results in the aforementioned effects and how they can be explained by data use expectations and collaboration. This paper addresses both issues by describing and explaining data use effects via a large-scale (...) study in Flanders. Data collected from 1472 teachers indicate that, although teachers are moderately positive about the extent to which data use results in different types of effects, data use effects cannot be taken for granted. Structural Equation Modelling shows that explicating data use expectations and data use collaboration are essential in order to facilitate data use effects in schools. (shrink)