Reasoning about processes: a logico-philosophical investigation

Informations projet

PROCESS REASONING

N° de convention de subvention: 892905

DOI

10.3030/892905

Projet clôturé

Date de signature de la CE 4 Mars 2020

Date de début 1 Janvier 2021

Date de fin 31 Decembre 2022

Financé au titre de

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Coût total

€ 207 312,00

Contribution de l’UE

€ 207 312,00

Coordonné par

AARHUS UNIVERSITET
Denmark

Periodic Reporting for period 1 - PROCESS REASONING (Reasoning about processes: a logico-philosophical investigation)

Période du rapport: 2021-01-01 au 2022-12-31

Résumé du contexte et des objectifs généraux du projet

This research project was a logico-philosophical investigation into the formal aspects of process ontology against the background of an open future. The core metaphysical picture is this: the world is constantly changing, full of happenings and doings, and there are alternative future possibilities. Until a couple of years ago, static world views were the mainstream position, but currently dynamic world views are on the rise. The last decades have witnessed a growing interest in process ontologies, and the intuitive idea of a dynamic reality has also gained traction in the current debate on dispositions and powers. The formal aspects of such views are, however, notoriously under-investigated, and the metaphysical debate is in need of clarification. A thorough dynamic basis is also a desideratum in related disciplines, such as linguistics and computer science, where processes and change are relevant to capturing the variety of aspectual properties and modelling concurrent actions.

The overall aim of this project was to develop a formal framework for representing processes and reasoning about them in an indeterministic setting that is philosophically well-informed and which ties in with the study of tense and aspect in linguistics as well as with logics of action in computer science. Central to the project was the utilisation of the transition approach developed by the researcher in her PhD thesis and subsequent work. The project pursued three objectives: (1) to provide a formal conceptualisation of processes and their modal-temporal properties in terms of transitions, (2) to implement the idea in a modal-temporal logic, and (3) to explore potential applications of the account to pertinent themes in linguistics and computer science. Building on the transition approach, the project provided a novel foundation for processes, shedding new light on our thinking about their dynamics.

Travail effectué depuis le début du projet jusqu’à la fin de la période considérée dans le rapport et principaux résultats atteints jusqu’à présent

The work carried out towards the first objective was primarily philosophical analysis and conceptual modelling. The researcher critically examined extant classifications of processes in the philosophical and linguistic literatures and clarified the ontological status of transitions. She developed a formal representation of telic processes in terms of transitions as progressions towards a goal, which may or may not be reached due to future interactions or interventions, and showed how the notion of dynamicity is encapsulated in their temporal unfolding.

The second objective was based on formal logic, especially modal-temporal logic. Its mathematical foundation was the transition semantics for branching time developed by the researcher. Aiming at a logical framework for reasoning about processes and their interrelation with modality and time, the researcher enriched the models of transition semantics with the formal representation of processes and experimented with different formal languages for describing the models. This paves the way for a meta-logical investigation, including the development of a proof system.

The third objective focused on potential applications of the resulting system in linguistics and computer science. Considerations concerning the intricacies of tense and aspect in English played a prominent role in the development of the conceptual and logical apparatus. At the centre of these investigations was the so-called imperfective paradox: “I was baking a cake” does not imply “I baked a cake”; something may intervene. The researcher also published a paper which highlights the merits of the dynamic nature of the transition approach in the analysis of the modal-temporal properties of conditional sentences. On the computer science side, she evaluated her account against prevailing logics used for modelling interaction processes in computer science, bringing out the merits of her framework in that field.

The project results were disseminated through presentations at research seminars and international workshops and conferences and a publication in a highly-ranked interdisciplinary journal. The paper “What If, and When? Conditionals, Tense, and Branching Time” is openly accessible at Linguistics and Philosophy via this link: https://doi.org/10.1007/s10988-022-09375-w. Halfway through the project, the researcher organised a two-day international online workshop “Formal Accounts of Powers, Processes, and Change”, which brought together researchers interested in the formal aspects of a dynamic reality.

Progrès au-delà de l’état des connaissances et impact potentiel prévu (y compris l’impact socio-économique et les conséquences sociétales plus larges du projet jusqu’à présent)

The problem of change is a very old one, with important repercussions on many current debates. The novelty of the approach developed in the present project can best be illustrated by considering Zeno’s arrow paradox: if the movement of the arrow solely consists in the arrow occupying different positions at different times, then, at any such point in time, there is no motion. How then is motion possible? Advocates of the dynamic world view reject the point-based picture underlying Zeno’s paradox, denying the possibility of reducing processes to sequences of static states. As a formal remedy, block-based accounts have been introduced, which conceive of happenings and doings as temporal expanses. The main representatives of the block-based accounts are the event and interval frameworks prevalent in linguistics and computer science. In such accounts, the movement of the arrow is viewed as an event that occurs during a temporal interval. The present project developed a robust alternative to such block-based accounts. Crucially, whereas block-based accounts model happenings and doings from a global perspective, the present approach models processes from a local perspective in time. Here, the movement of the arrow is thought of as a pointing towards a possible future state, i.e. the movement is itself a (mathematical) arrow. This makes room for interaction and intervention. In the end, the modal-temporal structure of the world is dynamically derived from the underlying processes rather than being rigidly presupposed.

The novel approach pursued in the present project has a formal and strongly technical character. This allows for a precise formulation of the ideas and opens the door for applications in linguistics and computer science. The framework is tailored towards a solution to the imperfective paradox in linguistics, and it is suitable for representing interaction processes in computer science, where it gains practical relevance in modelling artificial agents capable of planning locally and responding flexibly to interventions. The potential users of the project results are philosophers and scientists working in these neighbouring disciplines. The results are expected to open up new ground in these areas and will hopefully trigger future research on the topic of change.

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