Vincent F. Hendricks

Reliable Belief Revision

Philosophical logicians proposing theories of rational belief revision have had little to say about whether their proposals assist or impede the agent’s ability to reliably arrive at the truth as his beliefs change through time. On the other hand, reliability is the central concern of formal learning theory. In this paper we investigate the belief revision theory of Alchourron, Gardenfors and Makinson from a learning theoretic point of view.

Identification of Matrices in Science and Engineering

Engineering science is a scientific discipline that from the point of view of epistemology and the philosophy of science has been somewhat neglected. When engineering science was under philosophical scrutiny it often just involved the question of whether engineering is a spin-off of pure and applied science and their methods. We, however, hold that engineering is a science governed by its own epistemology, methodology and ontology. This point is systematically argued by comparing the different sciences with respect to a particular set of characterization criteria.

Proof Theory, History and Philosophical Significance

Preface. Contributing Authors. Introduction. Part 1: Review of Proof Theory. Highlights in Proof Theory S. Feferman. Part 2: The Background of Hilberts Proof Theory. The Empiricist Roots of Hilberts Axiomatic Approach L. Corry. The Calm Before the Storm: Hilberts Early Views on Foundations D. Rowe. Toward Finitist Proof Theory W. Sieg. Part 3: Brouwer and Weyl on Proof Theory and Philosophy of Mathematics. The Development of Brouwers Intuitionism D. van Dalen. Did Brouwers Intuitionistic Analysis Satisfy its own Epistemological Standards? M. Epple. The Significance of Weyls Das Kontinuum S. Feferman. Herman Weyl on the Concept of Continuum E. Scholz. Part 4: Modern Views and Results from Proof Theory. Relationships between Constructive, Predicative and Classical Systems of Analysis S. Feferman. Index.

Logic and Learning

Learning and learnability have been long standing topics of interests within the linguistic, computational, and epistemological accounts of inductive inference. Johan van Benthem’s vision of the “dynamic turn” has not only brought renewed life to research agendas in logic as the study of information processing, but likewise helped bring logic and learning in close proximity. This proximity relation is examined with respect to learning and belief revision, updating and efficiency, and with respect to how learnability fits in the greater scheme of dynamic epistemic logic and scientific method.

Informational pathologies and interest bubbles: Exploring the structural mobilization of knowledge, ignorance, and slack

This article contends that certain configurations of information networks facilitate specific cognitive states that are instrumental for decision and action on social media. Group-related knowledge and belief states—in particular common knowledge and pluralistic ignorance—may enable strong public signals. Indeed, some network configurations and attitude states foster informational pathologies that may fuel interest bubbles affecting agenda-setting and the generation of narratives in public spheres.

Off We Go

Unfortunately, that’s not all there is to say about that, even though the information age provides virtual oceans of information. First of all, information on which trivial as well crucial decisions are based may be tampered with, and second, personal belief, deliberation, decision, and action are influenced by what other people think or do. The aggregated opinion of others may influence our personal viewpoints. A paper was recently published in Science (Muchnik et al. 2013) that described an experiment on a social news aggregator platform and online rating system, the result of which testifies to massive social influence bias on individual users. On an unidentified crowd-based opinion aggregator system ostensibly “similar to Digg.com and Reddit.com,” the status of 101,281 comments made by users over a five-month period with more than ten million views and rated 308,515 times, was monitored. In collaboration with the service, the researchers had rigged the setup in such a way that whenever a user left a comment, it was automatically rendered with either a positive “upvote,” a negative “downvote” or no vote at all for control. Now, here is a key to the experiment: If a comment received just a single upvote, the likelihood of receiving another upvote for the first user to see it was 32 % relative to the control group. Additionally, chances were higher that such comments would proliferate in, or lemming to, popularity, as the upvote group had on average a 25 % greater rating than the control group. One of the lessons from this experiment is that

Assessment and Discovery in the Limit of Scientific Inquiry

Acquisition of knowledge may come about in different ways. One step on the way to acquire knowledge would be to formulate a hypothesis and then evaluate the particular hypothesis in light of incoming evidence. Inductive logics, confirmation theory, and Popper’s deductivist epistemology all adopt this approach. Indeed, proponents of this “generate and test” epistemology have insisted that the core of scientific method is exhausted by the study of methods of hypothesis assessment. This lead Reichenbach to formulate the classical distinction between the context of justification and the context of discovery. Hempel later spoke of a logic of justification but only of a context of discovery just to emphasize the discrepancy. Whether a hypothesis is verified or refuted by the evidence is strictly a logical matter which can be settled “out of court” in a logical or approximately logical fashion. However, it seems to be the case of many, at least early, confirmation theorists or justificationists, like Hempel, that they did not insist on convergence to a correct hypothesis. For them, confirmation was to be an end in itself. In consequence, one could confirm forever heading nowhere near the correct answer.

Agency and Interaction What We Are and What We Do in Formal Epistemology

Formal epistemology is a recent field of study in formal philosophy dating back only a couple of decades or so (Hendricks 2006; Helzner and Hendricks 2011). The point of departure of this essay is rooted in two philosophically fundamental and interrelated notions central to formal epistemology; agency – what agents are, and interaction – what agents do.

50 Years of Studia Logica: Editorial Introduction

In 1953, exactly 50 years ago to this day, the first volume of Studia Logica appeared under the auspices of The Philosophical Committee of The Polish Academy of Sciences. Now, 5 decades later the present volume is dedicated to a celebration of this 50th Anniversary of Studia Logica. It features a series of papers by distinguished scholars reflecting both the aim and scope of this journal for symbolic logic.

A note on innovation and justification

Within epistemology and the philosophy of science there is, in a number of cases, an a-symmetrical relation or even complementarity between innovation and justification. Innovations are not always justifiable, within the currently accepted body of scientific knowledge and readily justifiable innovations are seldom too interesting. This paper describes some such cases drawn from the history of science and attempts to classify different types of innovations.