We propose a solution to the problem of logical omniscience in what we take to be its fundamental version: as concerning arbitrary agents and the knowledge attitude per se. Our logic of knowledge is a spin-off from a general theory of thick content, whereby the content of a sentence has two components: (i) an intension, taking care of truth conditions; and (ii) a topic, taking care of subject matter. We present a list of plausible logical validities and invalidities for the logic of knowledge per se for arbitrary agents, and isolate three explanatory factors for them: (1) the topic-sensitivity of content; (2) the fragmentation of knowledge states; (3) the defeasibility of knowledge acquisition. We then present a novel dynamic epistemic logic that yields precisely the desired validities and invalidities, for which we provide expressivity and completeness results. We contrast this with related systems and address possible objections.

中文翻译：

---

逻辑全知的基本问题

我们提出了一个解决逻辑全知问题的方法，我们认为这是它的基本版本：关于任意代理和知识态度本身。我们的知识逻辑是从厚内容的一般理论衍生出来的，其中一个句子的内容有两个组成部分：(i) 内涵，处理真值条件；(ii) 一个主题，关注主题。我们列出了任意代理的知识本身逻辑的合理逻辑有效性和无效性列表，并为它们隔离了三个解释因素：（1）内容的主题敏感性；(2) 知识状态的碎片化；(3)知识获取的可废止性。然后，我们提出了一种新颖的动态认知逻辑，可以精确地产生所需的有效性和无效性，为此，我们提供了表现力和完整性结果。我们将其与相关系统进行对比并解决可能的异议。