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Claudio Conforti

viernes, 20 de enero de 2012

A defense of contingent logical truths Michael Nelson • Edward N. Zalta

Abstract A formula is a contingent logical truth when it is true in every model
M but, for some model M, false at some world of M. We argue that there are such
truths, given the logic of actuality. Our argument turns on defending Tarski’s
definition of truth and logical truth, extended so as to apply to modal languages with
an actuality operator. We argue that this extension is the philosophically proper
account of validity. We counter recent arguments to the contrary presented in
Hanson’s ‘Actuality, Necessity, and Logical Truth’ (Philos Stud 130:437–459,
2006).

God’s silence Elisa Paganini

Abstract Vagueness manifests itself (among other things) in our inability to find
boundaries to the extension of vague predicates. A semantic theory of vagueness
plans to justify this inability in terms of the vague semantic rules governing language
and thought. According to a supporter of semantic theory, the inability to find
such a boundary is not dependent on epistemic limits and an omniscient being like
God would be equally unable. Williamson (Vagueness, 1994) argued that cooperative
omniscient beings adequately instructed would find a precise boundary in a
sorites series and that, for this reason, the semantic theory misses its target, while
Hawthorne (Philosophical Studies 122:1–25, 2005) stood with the semantic theorists
and argued that the linguistic behaviour of a cooperative omniscient being like
God would clearly demonstrate that he does not find a precise boundary in the
sorites series. I argue that Hawthorne’s definition of God’s cooperative behaviour
cannot be accepted and that, contrary to what has been assumed by both Williamson
and Hawthorne, an omniscient being like God cannot be a cooperative evaluator of a
semantic theory of vagueness.

A case of confusing probability and confirmation Jeanne Peijnenburg

Abstract Tom Stoneham put forward an argument purporting to show that coherentists
are, under certain conditions, committed to the conjunction fallacy. Stoneham
considers this argument a reductio ad absurdum of any coherence theory of justification.
I argue that Stoneham neglects the distinction between degrees of confirmation
and degrees of probability. Once the distinction is in place, it becomes clear that no
conjunction fallacy has been committed.

A realist partner for Linda: confirming a theoretical hypothesis more than its observational sub-hypothesis, Theo A. F. Kuipers

Abstract It is argued that the conjunction effect has a disjunctive analog of strong
interest for the realism–antirealism debate. It is possible that a proper theory is more
confirmed than its (more probable) observational sub-theory and hence than the latter’s
disjunctive equivalent, i.e., the disjunction of all proper theories that are empirically
equivalent to the given one. This is illustrated by a toy model.

Walter the banker: the conjunction fallacy reconsidered,Stephan Hartmann · Wouter Meijs

Abstract
In a famous experiment by Tversky and Kahneman (Psychol Rev 90:293–

315, 1983), featuring Linda the bank teller, the participants assign a higher probability

to a conjunction of propositions than to one of the conjuncts, thereby seemingly committing

a probabilistic fallacy. In this paper, we discuss a slightly different example

featuring someone namedWalter, who also happens to work at a bank, and argue that,

in this example, it is rational to assign a higher probability to the conjunction of suitably

chosen propositions than to one of the conjuncts. By pointing out the similarities

between Tversky and Kahneman’s experiment and our example, we argue that the participants

in the experiment may assign probabilities to the propositions in question in

such a way that it is also rational for them to give the conjunction a higher probability

than one of the conjuncts.