This paper describes how knowledge bases can be represented in and reasoned with in natural logic. Natural logic is a regimented fragment of natural language possessing a well-defined logical semantics. As such, natural logic may be considered an attractive alternative among the various knowledge representation logics such as description logics. Our version of natural logic expands formal ontologies with affirmative propositions expressing a variety of relationships between concepts. It comprises (nested) restrictive relative clauses and prepositional phrases and, as a new construct, adverbial prepositional phrases. The natural logic knowledge base is to be used for deductive query answering applying inference rules. This is facilitated by introduction of Datalog as an embedding meta-logic. The inference rules are stated in Datalog and act directly on the natural logic formulations. The knowledge base propositions are decomposed into a graph form enabling path finding between concepts. The examples in the paper are derived from text source life-science descriptions.

本文描述了如何在自然逻辑中表示和推理知识库。自然逻辑是自然语言的组成部分，具有明确的逻辑语义。这样，自然逻辑可以被认为是诸如描述逻辑之类的各种知识表示逻辑中有吸引力的替代方案。我们的自然逻辑版本通过肯定性命题扩展了形式本体，表达了概念之间的各种关系。它包括（嵌套的）限制性相对从句和介词短语，以及作为新结构的副词介词短语。自然逻辑知识库将用于应用推理规则的演绎查询回答。通过引入Datalog可以促进此过程作为嵌入的元逻辑。推理规则在Datalog中声明，并直接作用于自然逻辑公式。知识库的命题被分解成图表形式，从而可以在概念之间找到路径。本文中的示例来自文本源生命科学描述。