形式：学术报告
时间：2009年6月19日(星期六) 上午9：00-12：00
地点：清华大学新斋335

演讲人一： 宋诗畅
题目：连续逻辑和概率论
摘要: 连续一阶逻辑是经典一阶逻辑的一个类比。和经典逻辑的二元真值表不同，连续逻辑的真值表是整个[0,1]区间。连续模型论拥有很多经典模型论所拥有的重要性质。虽然连续逻辑才刚被引入，它已在数学的分析学以及概率论中得到很多的应用。在这个讲座中，我先简述连续逻辑，然后再讨论其在概率论中的应用。最后，如果时间允许，我将谈论我在这个领域的一些最新进展。

演讲人二：Professor Dick de Jongh (University of Amsterdam)
题目：Comparing Strengths of Beliefs explicitly
摘要: Inspired by a similar use in provability logic, formulas p >_B q and ≥_B q are introduced in the existing logical framework for discussing beliefs to express that the strength of belief in p is greater than (or equal to) that in q. This explicit mention of the comparison in the logical language aids in defining several other concepts in a uniform way, viz. older and rather clear concepts like the operators for universality (which possibilities ought to be considered), together with newer notions like plausibility (in the sense of ‘more plausible than not’) and disbelief. Moreover, it assists in studying the properties of the concept of greater strength of belief itself. A heavy part is played in our investigations by the relationship between the standard plausibility ordering of the worlds and the strength of belief ordering. If we try to define the strength of belief ordering in terms of the world plausibility ordering we get some undesirable consequences, so we have decided to keep the relation between the two orderings as light as possible to construct a system that allows for widely different interpretations. Finally, after a brief discussion on the multi-agent setting, we move on to talk about the dynamics - the change of ordering under the influence of hard and soft information.