Over博士講演会The probability of counterfactuals (終了)


David Over博士が、日本学術振興会(企画者:神戸女学院大学 山 祐嗣教授)の招きにより来日しました。





Jonathan St.B.T. Evans & David E. Over「合理性と推理―人間は合理的な思考が可能か」

Over博士は日本で、札幌、東京、大阪などで複数の講演を予定していますが、京都大学では、下記の通り、前半は、若手対象(院生、若手研究者など)の小人数の密度の濃い研究会、後半は講演会を おこないました。


日時 2007年4月3日 火曜日 

場所 京都大学教育学部




1:30-3:30  Over先生を囲む若手研究会(2F215室)


"Cultural differences of regret under interpersonal and personal situation :US-Japan comparison.


The degree of belief in implicit assumption and the evaluation of enthymeme.


A Role of Causal Strength in Naive Reasoning


David Over


4:30-6:00 Over先生講演会(1F1講義室)  

タイトル:The probability of counterfactuals 


Counterfactual conditionals are of great interest in philosophy and psychology. These conditionals appear closely related to statements about causation and dispositions, and also to intense human feelings of regret and relief. Yet basic philosophical and psychological questions about them do not have agreed answers. There is not an accepted normative logical system for counterfactuals, and cognitive psychologists have only just started to investigate people’s actual counterfactual reasoning. One basic question is about the relation between counterfactual and indicative conditionals. I will try to clarify this relation by discussing inferences from disjunctive statements. Another basic question is how people come to have a degree of confidence in counterfactuals. I will describe psychological research with my collaborators that attempts to answer this question. In our theory, a counterfactual conditional, “if p had been the case, then q would have been”, is closely related to an indicative conditional, “if p then q”, stated earlier in time. The subjective probability of the counterfactual is the probability of the indicative conditional at that earlier time. The subjective probability of the indicative is itself determined by a process of hypothetical thought, which has the result that its probability is the conditional subjective probability of q given p. I will review the experimental evidence for this theory and discuss its problems and limitations.



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