Posts Tagged ‘Bart Verheij’

7th eColloq on Argumentation
Thursday April 11, 4-6 pm GMT+1  (Amsterdam, Berlin, Rome, Stockholm)
4.00-4.10 Connect, Welcome
4.10-4:35 Bart Verheij (Groningen, The Netherlands):
Defeasible rule-based arguments with a logico-probabilistic foundation
Abstract: A theory of defeasible arguments is proposed that combines logical and probabilistic properties. This logico-probabilistic argumentation theory builds on two foundational theories of nonmonotonic reasoning and uncertainty: the study of nonmonotonic consequence relations (and the associated minimal model semantics) and probability theory. A key result is that, in the theory, qualitatively defined argument validity can be derived from a quantitative interpretation. The theory provides a synthetic perspective of arguments `jumping to conclusions’, rules with exceptions, and probabilities. The approach is compared to Pollock’s computational model of argumentation OSCAR, designed on the basis of his well-developed positions concerning the relations between argumentation, logic and probability. In contrast with Pollock’s OSCAR, the present approach is compatible with the standard probability calculus.
4:35-4:50 Discussion
4:50-5:00 Break
5:00-5:25 Emmanuel J. Genot (Lund University, Sweden):
The Myth of a Confirmation Bias (Arguments for a better argumentative theory of reasoning)
Abstract: Wason, confronted with an apparent instance of the Fallacy of Affirming the Consequent in his empirical Selection Task, hypothesized a “Confirmation Bias” (CB) to be responsible for subjects’ selections [4]. When Bayesian rational analysis of the selection task (RAST, [3]) substituted a richer probabilistic semantics to Wason’s truth-functional semantics, subjects’ selection emerged as being vindicated, and evidence for CB (in fact, any bias) vanished. Relevance Theorists later produced data that Bayesian models could not accommodate [1], yet without exhibiting evidence for biases of any sort. However, Relevance Theory has more recently been superseded by the Argumentative Theory of Reasoning (ATR, [2]), in which CB has returned with a vengeance, backed by an evolutionary narrative that pits “argumentative” and “logical” competences against one another. I will argue that this narrative is a remnant of the same truncated view of logic (and semantics) that informed Wason’s theorizing, but that argumentation-theoretic considerations are necessary to account for the data. To support this view, I will present a generalization of RAST that accounts for both standard and non-standard cases of ST (resp. from [3, 4] and [1]) once argumentative goals are “factored in,” but with an underlying semantics that undermines the very idea of “logical competence”—without which the CB is but a myth.
Girotto, Kemmelmeier, Sperber & van der Henst. “Inept reasoners or pragmatic virtuosos? Relevance and the deontic selection task”, Cognition, 2001, 81, B69-B7
Mercier & Sperber, Why do humans reason? Arguments for an argumentative theory. Behavioral and Brain Sciences, 2011, 34, 57-74.
Oaksford & Chater. A Rational Analysis of the Selection Task as Optimal Data Selection. Psychological Review, 1994, 101, 608-631
Wason, Reasoning About a Rule. Quarterly Journal of Experimental Psychology, 1968, 20, 273-281
5:25-5:40 Discussion
Discussants (preliminary list)
Nir Oren (University of Aberdeen, UK)
David Hitchcock (McMasters, Canada)
Thomas Gordon (Berlin, Germany)
Jean Goodwin (Iowa State, USA)
Iowan Drehe (University of Cluj-Napoca, Romania)
Sune Holm Petersen (Copenhagen University, Denmark)
Steven Patterson (Marygrove College, Detroit, USA)
Sarah Uckelman (Ruprecht-Karls Universität Heidelberg, Germany)
Marcin Lewinski (New University of Lisbon, Portugal)
Thomas Fischer (University of Houston, Texas, USA)
To participate as a discussant (just “sitting in” is in fact fine!), please review the links under “TechThings” at the above website (to test your hardware) and contact the organizer at frank.zenker@fil.lu.se.
Frank Zenker
Department of Philosophy & Cognitive Science
Kungshuset, Lundagård, 222 22 Lund, Sweden

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"Homme assis" by Roger-Noël-François de La Fresnaye, c.1914

In a recent blog post provocatively titled “Kurt Vonnegut turns Cinderella into an Equation” Robert Krulwich (co-host of the excellent WNYC series Radiolab) uses a wonderful pair of cartoons to suggest that if humans are creatures who thrive on pattern, then scientists and mathematicians are compulsive pattern finders,  “pattern addicts” as it were.  Logicians and students of argument, I think, fairly belong in this category as well. Some of us talk about logical form and explain it in terms of complicated relationships between abstract symbols and letters. Or we classify arguments by scheme and develop equally schematic lists of questions with which to test their merits. The dialectically inclined among us give us patterns of argumentation between two or more arguers.  We create argument diagrams, relevance cubes, maps of controversies and many more things like them besides. We’re pattern people. There’s no doubt about it.

Interestingly, Krulwich closes his post by suggesting that even more than than scientists and mathematicians (and perhaps logicians and argumentation scholars too?) artists and storytellers may be even more pattern-aware. As exhibit the first he offers this short (and altogether too good not to reproduce) video of the legendary Kurt Vonnegut:

Let us begin with the obvious: we don’t need Vonnegut to tell us that stories have patterns too (though of course his way of telling us is very entertaining and we’re very lucky to have it). Clearly they’re there. The deeper issue has to do with the nature and significance of such patterns. How do we interpret them? How do we reason about them? How do we reason with them?


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