• Korean Journal of Logic
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• v.14 no.3
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• pp.27-59
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• 2011

This paper concerns several versions of conditionalization. In particular, I will examine the relationship between Jeffrey conditionalization and the second order conditionalization concerning updating higher order credences. In section 2, I suggest explicitly what Jeffrey conditionalization and the second order conditionalization are. I will argue in section 3 that Jeffrey conditionalization conflicts with van Fraassen's Reflection Principle while the second order conditionalization doesn't. And I will also argue in section 4 that under some situations, Jeffrey conditionalization may lead agents to Moorean absurdity while the second conditionalization may not. As a result, I will claim that Jeffrey conditionalization is better than the second order contionalization at updating our higher order credences.

• Korean Journal of Logic
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• v.18 no.2
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• pp.167-195
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• 2015

This paper aims to respond to Weisberg's claim that the standard Bayesian epistemology cannot model an agent's belief updating that is triggered by some undermining evidence. Our epistemological intuition seems to require that the undermining evidence decreases some particular relevant credences. According to Weisberg, however, such a belief change cannot result from the standard Bayesian belief updating rules-i.e., (Jeffrey) Conditionalization. This is because probabilistic independence between some propositions is preserved under (Jeffrey) Conditionalization on the relevant evidence. Yet I will show in this paper that this conclusion is somewhat hasty. In particular, I will show that there is another version of Conditionalization and that when one updates her credences by means of such a version, the belief updating originated in undermining evidence can be well modeled in the Bayesian framework. Some authors often call the version Higher Order Conditionalization.

• Korean Journal of Logic
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• v.11 no.2
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• pp.93-125
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• 2008

The radical probabilitists deny that propositions represent experience. However, since the impact of experience should be propagated through our belief system and be communicated with other agents, they should find some alternative protocols which can represent the impact of experience. The useful protocol which the radical probabilistists suggest is the Bayes factors. It is because Bayes factors factor out the impact of the prior probabilities and satisfy the requirement of commutativity. My main challenge to the radical probabilitists is that there is another useful protocol, q(E|$N_p$) which also factors out the impact of the prior probabilities and satisfies the requirement of commutativity. Moreover I claim that q(E|$N_p$) has a pragmatic virtue which the Bayes factors have not.