MCMP – Epistemology

Eleonora Cresto (Buenos Aires) gives a talk at the MCMP Colloquium (7 November, 2013) titled "Group Knowledge and Probability". Abstract: The talk addresses the concept of group knowledge and its role in probability aggregation. I start by acknowledging that we often feel compelled to credit group agents with epistemic attitudes that are not held by any of their members. Nonetheless, I argue that ideally responsible agents also �find a deflationary pressure to ground such attitudes in concrete individuals, for purely conceptual reasons - out of coherence. As a result of this, epistemically responsible groups are conceived of as dynamic entities; correspondingly, group knowledge gets defined in terms of a family of possible paths between distributed knowledge and common knowledge. Public Announcement logics can then be endowed with new tasks and goals - among them, the task of monitoring the satisfaction of normative requirements by epistemically responsible agents. Next, I argue that this conception of group knowledge provides a principled way to deal with group probabilities. I begin by considering sets of individual measures conditional on common and distributed knowledge, respectively. The proposal is further refined with the addition of a geometric pooling method on the conditional measures. The resulting aggregation procedure is shown to be in partial agreement with some proposals found in the recent literature. I contend, however, that a full-fledged understanding of group probabilities should focus on the distance between the two aggregated sets, and in the possible strategies to reduce it.

Alexander Bird (Bristol) gives a talk at the MCMP Colloquium (24 July, 2013) titled "Externalism, Internalism, and the KK Principle". Abstract: The KK principle states that if a subject knows some fact then she is in a position to know that she knows that fact. This paper examines the relationship between the KK principle and the epistemological externalism and internalism. There is often thought to a very close relationship between externalism and the rejection of the KK principle and between internalism with its acceptance. How strong are the connections? The stronger proposals are: externalism entails the denial of the KK principle; internalism entails the truth of the KK principle. We will consider a number of problems for the theses as stated; we examine two ways of amending them so that they avoid these problems.

Dana Scott (CMU Pittsburgh and Berkeley) gives a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "Stochastic Lambda-Calculi".

David Etlin (MCMP/LMU) gives a talk at the MCMP Colloquium (21 November, 2013) titled "Vague Desire: The Sorites and the Money Pump". Abstract: The similarity between the sorites paradox of vagueness and the money pump of decision theory has been noted by Dummett (in "Wang's Paradox"), but the connection has not been widely recognized or developed. We argue that on one plausible philosophical theory of linguistic meaning, the Gricean intention based account (as developed in Schiffer's "Meaning"), the paradox of vagueness turn out to be a puzzle about intransitive preferences. Given this, one can solve the sorites paradox by diagnosing the appealing but mistaken principle connecting preference and choice leading to the money pump. We argue for a resolution of the money pump having consequences not only for diachronic principles of rational choice, but also the standard synchronic principle of rationalizable actions. Our approach to vagueness helps overcome worries about the arbitrariness of rejecting instances of the sorites step, and also supports a treatment of vague expressions that don't immediately lend themselves to soritical reasoning.

Aidan Lyon (MCMP/LMU) gives a talk at the MCMP Colloquium (6 November, 2013) titled "Measuring Overconfidence with Imprecise Probabilities & The Wisdom of Collective Credences". Abstract: What explains the Wisdom of Crowds effect? Page (2008) has made some initial progress on this question with what he calls the Diversity Prediction Theorem. The upshot of the theorem is that if a collective has some diversity to it, then the collective’s estimate is guaranteed to be more accurate then the typical estimate in the collective. This appears to be a simple and very general account of the Wisdom of Crowds effect. However, for the theorem to have explanatory power, it needs to be supplemented with additional assumptions. In this paper, I analyse these assumptions, and discuss their drawbacks, and how we might overcome them. A consequence of this analysis is that the Wisdom of Crowds effect behaves very differently for probability estimates than it does for regular quantity estimates.

Sean Walsh (Irvine) gives a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "Empiricism, Probability, and Knowledge of Arithmetic".

Arthur Paul Pedersen (Max Planck Institut for Human Development) gives a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "Great Expectations. Strictly Coherent Preferences, No Holds Barred".

Glauber de Bona (Sao Paulo) gives a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "Towards Classifying Propositional Probabilistic Logics".

Jon Williamson and Jürgen Landes (University of Kent) give a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "Objective Bayesian epistemology for inductive logic on predicate languages".

Teddy Groves (University of Kent) gives a talk at "Progic 2013", the Sixth Workshop on Combining Probability and Logic (17-18 Sept, 2013), titled "An application of Carnapian inductive logic to philosophy of statistics".