Approaching probabilistic truths:introduction to the Topical Collection

After Karl Popper’s original work, several approaches were developed to provide a sound explication of the notion of verisimilitude. With few exceptions, these contributions have assumed that the truth to be approximated is deterministic. This collection of ten papers addresses the more general problem of approaching probabilistic truths. They include attempts to find appropriate measures for the closeness to probabilistic truth and to evaluate claims about such distances on the basis of empirical evidence. The papers employ multiple analytical approaches, and connect the research to related issues in the philosophy of science

Convergence argument against the challenge of “unconceived alternative theories”

Kyle Stanford (2001, 2006a) poses a new challenge to scientific realism, known as the “new pessimistic induction.” According to him, for each theory chosen by scientists, a class of theories exists with radically distinct ontological claims but equal explanatory power. Therefore, no theory can be considered as the only theory or the best theory. As a result, the realistic approach to its unobservable entities is unjustified. This paper tries to use the idea of convergence against this challenge. The first part of the paper emphasizes that, according to the new pessimistic induction, given the unlimited number of unconceived alternative theories for each successful theory, the possibility of “encountering” and “uniting” independent theories will be very unlikely. Meanwhile, the history of science recurrently displays convergence and multiple discoveries. In the second part, an attempt is made to respond to the general critiques of the idea of convergence

Social Aspects of Scientific Knowledge

published online 2018-07-12From its inception in 1987 social epistemology has been divided into analytic (ASE) and critical (CSE) approaches, represented by Alvin I. Goldman and Steve Fuller, respectively. In this paper, the agendas and some basic ideas of ASE and CSE are compared and assessed by bringing into the discussion also other participants of the debates on the social aspects of scientific knowledge-among them Raimo Tuomela, Philip Kitcher and Helen Longino. The six topics to be analyzed include individual and collective epistemic agents; the notion of scientific community; realism and constructivism; truth-seeking communities; epistemic and social values; science, experts, and democracy.Peer reviewe

Belief Integration and Source Reliability Assessment

Merging beliefs requires the plausibility of the sources of the information to be merged. They are typically assumed equally reliable when nothing suggests otherwise. A recent line of research has spun from the idea of deriving this information from the revision process itself. In particular, the history of previous revisions and previous merging examples provide information for performing subsequent merging operations. Yet, no examples or previous revisions may be available. In spite of the apparent lack of information, something can still be inferred by a try-and-check approach: a relative reliability ordering is assumed, the sources are integrated according to it and the result is compared with the original information. The final check may contradict the original ordering, like when the result of merging implies the negation of a formula coming from a source initially assumed reliable, or it implies a formula coming from a source assumed unreliable. In such cases, the reliability ordering assumed in the first place can be excluded from consideration. Such a scenario is proved real under the classifications of source reliability and definitions of belief integration considered in this article: sources divided in two, three or multiple reliability classes; integration is mostly by maximal consistent subsets but also weighted distance is considered. Other results mainly concern the integration by maximal consistent subsets and partitions of two and three reliability classes

Cambiamento teorico, abduzione e verosimilitudine. Aspetti filosofici ed epistemologici della teoria AGM

2011/2012La tesi affronta il tema del cambiamento sia nell’ambito dell’epistemologia in senso stretto – seguendo le concezioni del fondazionalismo e del coerentismo - sia nell’ambito della filosofia della scienza. Negli ultimi decenni, i filosofi della scienza hanno affrontato l'analisi del cambiamento teorico razionale e del progresso scientifico, spesso ispirandosi all'idea di Popper per cui “la scienza è una delle pochissime attività umane – se non l’unica – in cui […] possiamo chiaramente e razionalmente parlare di progresso. In tutti gli altri domini soggetti agli sforzi umani vi è mutamento, ma raramente un progresso” (Popper, 1963, pp. 371-372). La teoria AGM del cambiamento teorico, soprattutto nei suoi sviluppi più recenti, sembra poter dare un contributo all’analisi del progresso scientifico. Tale teoria ci dice come un agente idealmente razionale - sia questo un individuo qualunque, uno scienziato, una comunità scientifica o un computer – cambia il suo stato epistemico, cioè l’insieme di tutte le sue credenze, alla luce di nuove informazioni (input); le possibili operazioni di cambiamento di credenze sono l’espansione, la contrazione e la revisione. Si è visto che la teoria AGM offre gli strumenti logici e concettuali per studiare in una nuova luce alcuni problemi tradizionali di filosofia della scienza, come il problema di Duhem, la distinzione tra centro e periferia nel sistema di credenze di Quine e il cambiamento dei programmi di ricerca di Lakatos. Sono stati, inoltre, analizzati i rapporti tra teoria AGM e abduzione come inferenza alla miglior spiegazione - illustrando espansione e revisione abduttive - e tra AGM e verosimilitudine (o approssimazione alla verità). L’aver messo in relazione questi tre campi di ricerca - AGM, abduzione e verosimilitudine - ha portato un unico frutto ancora acerbo. Si è dimostrato, cioè, che dati una teoria vera, un input e un’ipotesi abduttiva che lo spieghi (ovviamente diversa dall’input) anch’essi veri, se aggiungiamo alla teoria oltre all’input anche l’ipotesi abduttiva ci avviciniamo maggiormente alla verità rispetto all’aggiunta del solo input. In questo caso specifico e non particolarmente interessante, un’espansione abduttiva ci porta più vicino alla verità rispetto alla corrispondente espansione AGM tradizionale, poiché il risultato è maggiormente informativo. Sulla base di queste considerazioni si stanno facendo i primi passi verso una formulazione di condizioni plausibili in grado di specificare le circostanze in cui il cambiamento abduttivo delle nostre teorie, prodotto da nuove informazioni, aumenti la verosimilitudine di tali teorie.XXV Ciclo197

Acceptance, Aggregation and Scoring Rules

As the ongoing literature on the paradoxes of the Lottery and the Preface reminds us, the nature of the relation between probability and rational acceptability remains far from settled. This article provides a novel perspective on the matter by exploiting a recently noted structural parallel with the problem of judgment aggregation. After offering a number of general desiderata on the relation between finite probability models and sets of accepted sentences in a Boolean sentential language, it is noted that a number of these constraints will be satisfied if and only if acceptable sentences are true under all valuations in a distinguished non-empty set W. Drawing inspiration from distance-based aggregation procedures, various scoring rule based membership conditions for W are discussed and a possible point of contact with ranking theory is considered. The paper closes with various suggestions for further research

Understanding scientific study via process modeling

This paper argues that scientific studies distinguish themselves from other studies by a combination of their processes, their (knowledge) elements and the roles of these elements. This is supported by constructing a process model. An illustrative example based on Newtonian mechanics shows how scientific knowledge is structured according to the process model. To distinguish scientific studies from research and scientific research, two additional process models are built for such processes. We apply these process models: (1) to argue that scientific progress should emphasize both the process of change and the content of change; (2) to chart the major stages of scientific study development; and (3) to define “science”